2005 dodge magnum RT 5.7- Cranks but no Start, Starts By Gas pedal then Stalls..

I will paste the question as I Typed out. Don't mind the order, thx

"I was working on the car trying to find the problem as to why it won't start but cranks perfectly and all the ligts on the cluster including the check engine light, and obd-2 bluetooth adapter connects to it and gives me the codes and stuff...

it had no problem but the gas pedal was not moving freely so thought throttle body might have carbon buildup, but found out i cleaned a while back and its clean, while doing that in the cold weather, broke voltage wire on the injector-3 harness and no big deal attached it together and checked the continuity and its good(its not the issue but just mentioning the series of action that happened).

i just sprayed little lubricant near the pedal and its fine now...
I did all the checks from ASD relay to fuel relay and looked a lot of wiring diagrams in the service manual...so please don't think that i won't be able to understand if you tell me something to check. Learnt from you. most of the basic stuff I might have already checked and will be able to answer if you ask me to check them. Its like I am at the spot where I am thinking its computer but I checked the power(Fused B+) wire and two ground wires coming to the PCM on the c1 harness...they are good and I checked the 5v on pin-27 C1 harness and i see 4.95v.

and also saw the 5v coming in to couple of sensors intake air sensor and EGR sensor as they were easy to pull out....little worried/not 100% sure about testing the ground, little bit confuse at this point ground is working fine or not because PCM is controlling the ground to ASD, fuel pump and other relays which seems to me that its not giving it since I was not able to see the controlled ground given by pcm to ASD relay and fuel relay..(Confirmed at the pcm that its not giving chasis ground to fuel pump relay (pin-86)upon key-on for 3 seconds (chrysler says in the manual) also the same for asd relay, which in turn is giving 12v to the injectors via injector, coils fuse....

so no ASD relay activation, not able to see the asd relay activation(no click on the relay). read that ASD relay also activates initially for 3 seconds or 1 second then stops before we start the engine or something. in short didn't heard any clicks when key-on. and no clicks on fuel relay too....if I jump the asd relay when key-on form 30-87, i see battery voltage going to injector fuse and the injectors get the voltage but no test after that...

if jumped fuel relay, i hear the fuel pump running....
initially i thought the security light on the dash is causing it, but i did try starting when there is no light there and the key fob working, as key fob was also not working in conjunction with that security light showing up stable while ignition on...

I had to leave the battery unplugged overnight, so make key fob work...
so right now i am using a battery jumper, high cranking amps on this jumper battery...
The only way the car starts for 1 or 2 seconds is by pressing the gas pedal to the floor and by just pressing and releasing it and finding the spot to start the engine, but it does that only for couple of seconds, i see the rpm, fuel guage working. rpm guage starts high as I pressed the gas pedal to start the car but then goes down and stalls in couple of seconds...

right now even after clearing the codes, I see P0031,p0037,p0051,p0057 o2 sensors heater circuit low codes, and i saw P0406 too, may be because i had removed it to check 5v ...I just wanted to type it what happened and where am I so that I don't waste your time......

Will wait for your reply Paul, I know I typed in too much..

Fuse Diagram: fusesdiagram.com/dodge/fuses-and-relay-d...er-dodge-magnum.html


PCM connectors pin-outs on Page-3500
Service manual : www.dropbox.com/s/ofo6epl4aclda91/2006-2...orkshop%20Manual.pdf

Please don't hesitate to ask me to check anything. Will do that and probably have done most of the stuff now.

Thanks for your help in advance.

HI
If you look up your codes you will find that they all have the same ground G109 this is a common factor that you need to check out.

As for the hard start check all your temp sensors when the engine is cold they should all be the same

Clear the codes and see what codes come right back and id there is a few look at the codes and look for the cause that will trigger all of them..

Good luck
Doc

thank you so much for replying..I have been posting questions to many forums and didn't get a single reply..

Initially I believe there was no codes but may be it was just waiting to come out , i am talking about when i fix the littl ebroken wire on injector-3 harness which is common to all the other. but thats not the problem here i checked the continuity and i joined them together fine..

1) The P0406- I myself will ignore it because it came up after I started he car the way its want to and anytime i does that depending on the no. of restarts , i get white smoke for a second, not sure if its because fuel is flooded or something.

but the codes consistently coming back up are those p0031 to p0057 for oxygen sensor, low circuit...

2) There was code U3000 came up for network, which is also one of the reason i thought it could be computer, but i can plug in obd-2 connector and get codes...

3) Yes, I saw that G109 which is common for front o2 sensors but there is no location in the manual for that and the other rear o2 sensors have G100( I looked but didn't see it there or may be I missed it down somewhere...will have to see the location.
Please let me know the G109 location .

4) I am using torque pro app for the codes ad stuff..it also has graphs to select to and i think i saw the temp sensors like Intake air temp, and it was 33 degree something (outside temp). Please let me know the list of temp sensors that I should check..

5) I was looking for voltage on the o2 sensor heater control pin for front o2 sensors to start with on pcm harness with ignition-on. But I didn't back probe it, I removed the c2 and c3 harness but connected the c1 harness(Black ) , i didn't see anything..this time pcm is power controlling the o2 sensors only.. the fuel, asd are ground controlled...

Much appreciate your help.

Doc n2mx wrote: HI
If you look up your codes you will find that they all have the same ground G109 this is a common factor that you need to check out.

As for the hard start check all your temp sensors when the engine is cold they should all be the same

Clear the codes and see what codes come right back and id there is a few look at the codes and look for the cause that will trigger all of them..

Good luck
Doc

Just to be more accurate, if I delete the codes , they all come up but P0037 shows right off the bat as current fault and others show pending....but they do come as pending if i try starting the car couple of times...

Much appreciate your help.

Can anyone please reply.....

Try the loaded ground test because it's not good to test grounds when the cars just sitting off, test the ground while car is cranking !

Connect test light to battery negative and touch on those ground points while you crank the car over. Test light lighting means bad ground.

G100

I was able to see G100 for some reason , would that be still beside the engine on the left side after the shock box and before the headlight? or its above the wheel when you look underneath the fender....any actual car pic would be great....

can I use multimeter? i don't have a test light...

1) can I do this, I will put the multi meter in to continuity mode where i can hear beep, and connect it to the battery ground and connect the other to these grounds while cranking.. if I loose the beep then it means we saw a bad ground there right?
doing either of the test will be lil hard because the battery is in the trunk..i havea 12 feet 8 guage jumper/booster wire..shall i use that?

2) Another question, I normally thought that if you touch two wires or a metal piece with the multimeter in beep/continuity mode, you see value 0.00 or close , you hear a beep. But I noticed that if I just touch positive and negative of a relay or infact just a plain car battery + & -, you hear the beep for continuity but the value is live 680 something on the screen... that make sense? whats the criteria for continuity though..

3) Does these codes for o2 sensors which we are trying to solve, stop the car from starting?
what do you want me to check for the car to start...it starts and stalls and only starts after pressing gas pedal to the floor and revving up and down to find a spot but dies after rpm drops on guage...

4) Just wanna add this, not sure if I said this earlier in the post. that since my key fob was not working and the security light was showing on the dash when i attached the jumper battery after 3 weeks, I left the battery negative unplugged and saw key fob working but i think I didn't try starting the car at that moment... later i found out , could be the security stopping it because there was nothing wrong with the car at all... been sitting for weeks before , started right away..anyways. so i did unplug the negative and this time attached + & - to drain the capacitors etc to let the key fob work (did before couple of times before all this problems, nothing wrong with doing that) but next morning i attached the jumper in the front power/fuse module as the trunk will only open when u have power,the negative terminal here is that G102 and saw lil smoke coming out of the the positive terminal of that front power module. did removed it in a second...it happened because at the back + & - was together....
but saw no difference in anything, the car is same as what it was before this, start and stall only if pedal to the floor and without that just cranks good...

May be this o2 codes came after that, because if I remember correctly I didn't scan the code before but tried looking for them on the dash by doing the ignition sequence with the key...

In short, it didn't do anything wrong as per starting the car but may or may not have added those o2 codes. Visual inspection of that G102 is totally fine..Also saw G104 before, good..

Just wanted to add these notes, Will do that ground test you mentioned in crank position.

Thanks

I never used continuity test mode like that before.
Put the test light in DC mode 20V range if yours is not auto ranging. Put one end on battery negative and the other end on the eyelet. The current path goes from wire > eyelet > bolt > chassis. Crank engine and the voltmeter should report V and should stay as close to 0V as possible. That jumper wire will work fine.

I wrote incorrectly to do a loaded ground test, but that is not necessary. I was thinking of starter bad ground which calls for loaded ground test. G102 is a computer ground. Key on engine off will suffice. The voltage at that ground point should be less than 50mV. But all of this could be for nothing and there's nothing wrong with the ground. I would just unscrew the ground connection and give it a good 1 minute clean with a wire brush and reinstall it, but hey that's me.

I don't think o2 codes would stop a car from starting, but i may be wrong.

You wrote that the car is starting briefly but you also wrote you had no control side ground from PCM at ASD relay and no control side ground at the fuel pump relay. Is it starting briefly because you jumped the load side connectors?

I don't know anything about the anti theft device or keyfob stuff.

1) I will double check the ground thing with just ignition off, i did before the resistance test and 1 ohms... will do the voltage drop test...

2) The car is starting for a second or two with couple of tries and jumper battery being charged fully. and i can only do that couple of times before the jumper battery wont have sufficient voltage... I did amp draw test with the + & - wires of my car connected to my almost dead battery, i see 3A draw, i think its because the battery is drawing current from jumper battery to charge itself and if i eliminate the battery and then check it i saw 0.75A and this is after all the doors locked and waiting for long time to let other stuff shutoff automatically...

3) if I jump the fuel relay or the asd relay or if I don't do anything, i would say its starting the same way by gas pedal only for a sec or two.... I was jumping the pin-30 with pin-87 directly...should i jump the coil side relay first?

4) Also do you if the resistance or the ground test you mentioned should be zero for the pcm ground and chasis ground? meaning are these ground will be same.if yes then i checked the controlled ground both at the fuel relay and at the pcm too at the corresponding pin but no continuity between the chasis ground and the pin at pcm(for control ground). but if you connect one lead of meter to that pcm pin and other to battery positive , you see the voltage...same goes at the fuel relay side....

Please let me know if the pcm ground is same at chasis ground and do they should have continuity...

Thanks

I also noted yesterday that the top bulb on the headlight was on when the key was in on position but was not so bright...that could be the headlight itself or the hazard light (yellow), not sure as its aftermarket lights...

To me seems like a security issue but not sure...I do see the solid security light on dash , if i leave the battery overnight unplugged , sometimes it makes the keyfob work and i think at that time i may not see those lights...

How to solve this if it comes back again?

Thanks

1) I will double check the ground thing with just ignition off, i did before the resistance test and 1 ohms... will do the voltage drop test...

2) The car is starting for a second or two with couple of tries and jumper battery being charged fully. and i can only do that couple of times before the jumper battery wont have sufficient voltage... I did amp draw test with the + & - wires of my car connected to my almost dead battery, i see 3A draw, i think its because the battery is drawing current from jumper battery to charge itself and if i eliminate the battery and then check it i saw 0.75A and this is after all the doors locked and waiting for long time to let other stuff shutoff automatically...

3) if I jump the fuel relay or the asd relay or if I don't do anything, i would say its starting the same way by gas pedal only for a sec or two.... I was jumping the pin-30 with pin-87 directly...should i jump the coil side relay first?

4) Also do you if the resistance or the ground test you mentioned should be zero for the pcm ground and chasis ground? meaning are these ground will be same.if yes then i checked the controlled ground both at the fuel relay and at the pcm too at the corresponding pin but no continuity between the chasis ground and the pin at pcm(for control ground). but if you connect one lead of meter to that pcm pin and other to battery positive , you see the voltage...same goes at the fuel relay side....

Please let me know if the pcm ground is same at chasis ground and do they should have continuity...

Thanks

spent whole day finding out the problem,seems like ecm is fine in terms of asd, fuel relay and starter.. throttle body plate is not moving when key on and gas pedal pressed... took out the gas pedal, after I could not see any voltage at pin-3 on throttle body harness with key on and gas pedal pressed to say half using breaker bar..(pin-3= etc motor+, which is at ecm harness c2-pin6), etc- seems to be having good continuity with chasis ground..
so removed the gas pedal and checking its resistance at the position sensor to confirm if its sensor , if not then i should move to sensor harness to ecm circuit.....

can you tell me what to look for in terms of resistance or continuity (beep sound on multi-meter) on the Accelerator pedal position sensor....it has 6 pins..i hope you can find the diagram for my hemi...

will do that test first...i just dont wanna change it without confirming it...its like $140 part...

Also assuming its bad, can I just start the car by opening a vaccum like or opening throttle body plate manually little bit to let the air go inside...doesn't matter rich or lean idle...can i start that way? if yes, do I still need to plug this bad(if it is..lol) pedal to its harness then try to start with vaccum leak?

thanks

So here;s where I am at,

1) ETC is not bad i think because when key on, etc engages and flips its plate twice to engage itself,as if computer talking to it are you there... so i was also told by mechanic(online) that that means pcm and etc are good..
Since I already found that ETC+ to the throttle do not have any voltage, now its time to check accelerator position sensor at the gas pedal, which could be the culprit as car had water leak from sunroof may be, and water evaporated and did something...they say chrysler had that gas pedal sensor problem.

2) SO I nee the resistance check for the sensor itself.( Do you have it , please let me know)
(Here's what i found myself, multimeter in continuity mode, by the way sensor has two circuit it seems, pin 1(5v) to 3 and pin 6(5v) to 4, i see value between 1 & 2 , and 1 & 3 with or without pressing the pedal to actuate the sensor resistance and same is not true for 6 & 4 and 6 & 5 with or without pedal, no values all I see is '1' like infinity type.or open circuit.

3) Question, is it right what i did and do you have something to check which clearly says that if failed this is the sensor..

4) Just in case, I checked for any open or damaged wire from the sensor harness wires to pcm.. they are come and go to the pcm on this side of the circuit( we already know throttle to pcm wires are fine). so both sides wires are good, no open or damage..

5) Do you think the ETC is bad, when its not getting the ETC+ voltage....?

6) wondering if the o2 sensors codes i am getting p0031,0037,0051,0057 are related to gas pedal sensor, meaning if we can start the vehicle we might be able to run is on idle and delete codes and check again and probably not find those codes?
along with those i have EGR code too p0406( some mechanic said if u unplug it with key on it will show). but i deleted the code and gave ignition cycles but came back on the first one again...

Thanks

No all that pcm ground is sorted out and I mentioned that above , it weird with chryslers, the asd adn fuel relay only opens for 1 -3 seconds, so u need a second set of eyes , so finally i found everything with the pcm ground works fine...ETC motor d o not have ETC+ from pcm, so basically signal is not coming from pedal...

(problem created today- but it could be just be low jumper battery)
1) today while checking and cranking couple of times...finally the starter won't click or crank at all..may be batteyr gone low on jumper..forgot to check the headlight brightness to find out if its battery or i messed the starter...saw the voltage on starter fuse and quickly felt the start relay click... and the voltage was 11.9v something... can the start click a little bit at that voltage or its low to even crank a little bit?

2) so i am at pedal as no positive signal at the throttle from pcm because of pedal not sending signal, so obviously i haveto change the pedal sensor and see if the car starts right?

3) Are you saying you don't need the gas pedal sensor signal value to start the car?

very nice of you to be specific on the wires...yes i checked that pcm is providing two 5 v ref on pin1 and pin-6 to the APP sensor and i checked the wires form APP harness to pcm..they have continuity meaning no open wires..but in order to confirm if its not shorted to ground or battery voltage, I should test it by connecting the other lead of meter to ground adn battery voltage for continuity right or basically seeing if the resistance is zero to either of them then they are shorted to them...

1) I think i should check that because i tried to see the voltage on the signal wires coming from APP sensor when connected and key on and pedal pressed.. i was back probing the pcm on pin-25 and pin-36 on pcm harness c3..APP signal no 1 and no. 2, ...
I saw battery voltage on pin-36 when it was pressed and when released i saw zero voltage...i was like what it should not show more than 5v (actually less than that) but i removed the backprobe pin adn checked again..this time i saw no voltage, may be i didn't make the contact to the pin backprobing it i guess...(sunset so came back)...I think first time i made contact else it would not show me voltage when other lead connected to ground...

2) Since i do not know or have resistance value to correctly check the APP sensor itself alone, I am still doubting it but i ordered the part and will see if it solves it for the heck of it...the only reason i am saying it might have gone bad because after the water leak due to rain, water got evaporated and did some damaged to interior and the gas pedal started sticking when pressed and this troubleshooting started because of that and when i am back to it again it kind of made little sense to me to i ordered the part to check..., initially I was thinking gas pedal is getting stuck because of corrosion or something but its all plastic and gas pedal is not mechanical, so the sensor itself is holding it or something(read online too)..
so when i check the resistance in pin 1 & 2 and pin 1 & 3, i see some value with or without pedal but its not true for the pin 6 & 4 and 6 &5 which is basically the second circuit...it has two circuits for sensor signals...
so if one circuit is showing something other can't be having infinite resistance like OL, in my meter its '1'....

3) Will see what happens to the ETC motor + signal if it gets any signal or not...after changing the pedal..
Do you know does the ETC Motor + to throttle gets 12v or 5v from pcm?

4) do you need throttle to start the car and stay in idle? some mechanic online said you dont need gas pedal.. that made me think am I doing the diagnosis all wrong or what... he says to check the timing, compression....

5) Forgot to mention the pin-36 (signal 2 i think) showed battery voltage then showed zero, got to double check again if it showed a voltage then ti will show the same again not zero... but the pin-25 didn't show anything at all, did check twice.. will double check that too with pcm harness disconnected because those are inputs and i would be able to read them better with harness removed(c3 pcm harness)

Let me know what you think...Would Appreciate you reply in bullet points as above. thx

1) ok. will double check like that..I did that as a continuity test on the meter by isolating the circuit but gotta double check on how you mentioned it..
5v to 0v , then 0v to 5v--this kind of make me thinks if gas pedal is fine or what.... but anyways will see when the part arrives..can return it in this case..

2) No i was checking for the resistance on the pedal assembly alone without any harness or power connect.d to it, me saying by pressing the pedal is by hand to actuate the sensor...so that i can see if the resistance is changing on the signal pins.....etc

3) Interesting, thought for some reason its a 12v motor.. etc has a 5v ref wire and i see the voltage there, but there is also ETC motor + & - , i am assuming thats the actual voltage that will move the throttle plate..Here's the service manual with diagrams, just in case if you can refer to it...
www.dropbox.com/s/ofo6epl4aclda91/2006-2012 LX Workshop Manual.pdf
(you can search and go to any page without downloading the actual pdf file)

4) Yes car starts and stalls if i find the right stop by pressing gas pedal not brake pedal..didn't try nor do i think that might start my car...RPM needle drops and the car stalls even if try to rev it and keep it alive...can't keep alive for more than couple of seconds...

yes, one lead to ground and other lead to app signal 1 and 2...signal 2 (pin-36 at pcm) showed battery voltage(its shouldn't show that much voltage right) , tried checking second time by removing the T-pin and back-probing it again, no voltage( I might have not made a contact this time-will double check). signal no. 1 showed nothing....

5) if for some reason the timing and compression went bad just because i was pressing gas pedal to start and instead of starting or running at lower RPM in the cold weather, did i made the engine go bad with its timing or compression? i heard pops couple of times, when i tried starting after each steps of troubleshooting that i did leading up to now... atleast i hope that i did not break any piston or something...

Any throttle i guess is not closed 100%, they are always slightly tilted.....maybe 3% and little air goes thru them..i tried starting with someone holding the throttle plate ope a bit with a ratchet extension.. i tried starting it with gas pedal pressed to its sweet spot and it didn't stayed little longer just because i was giving air..it died....
==>Do u think if it was air problem, then it should have been in idle by me opening the throttle plate manually?if yes, where you would see the problem now... ?I later thought may be me doing that does mess up pcm readings and will make it not start...
fyi, i still have p0031,0037,0051,0057 o2 codes adn P0406 EGR ref 'A' circuit High code....

I hope the Gas pedal swap does the magic...

Thanks

1)I was thinking that pcm is not grounding ASD & fuel relay, but later found out it will do it for 3 seconds when KOEO , and activates them again when cranking and started. so I by myself was not seeing it because I am not flash , to back at the car after inserting key to test it..so had someone help, i can hear the fuel pump whining without any problem and also hear and feel ASD relay clicking...and since pcm also sends ground to starter relay , thats working fine too.
-> RPM signal --how to confirm that, is it near the ignition switch. when i start teh car with gas pedal pressed, the rpm needle moves if it started...but drops back to zero and stalls....at this point may be pcm not giving ground or rpm signal going bad...I wonder.
So for now in my mind PCM is good unless one component dealing with the starting system is gone bad or its stopping itself from give ground after one or two crank...not sure which others signals needed...cam and cnk as you said.

2) I am using torque pro app, i think i can see the pid's there on the chart. will double check on it. what reading i should see on them?

3) Will do that sound compression test..will remove fuel relay and see if it cranks the same way like its doing now or like a normall car start? Are we talking slightest difference in sound that you can hear only at the engine or sitting in the car? I have starting fluid and i see a small hole after the throttle body with a thin hose on it, i can spray on that...

4) some mechanic told the throttle should open and close when KOEO and gas pedal pressed...this is what made me buy the pedal..damn..
->if ETC is defaulted to the 1500 rpm, that means idle should not be a problem..so me chasing for the throttle plate to open even slightly to idle is wrong..I see now
->Yes the throttle open and close to do that test you mentioned

5) KOEO - Yes i saw the 5v on the pin-2 and ground continuity/0v at pin-5 (ETC motor -)
->Just so you know i was chasing the APP sensor and not throttle sensor because the only thing i didn't find at TPS is ETC motor + voltage....
->so to test the signal voltages on pin 1 & 4, do you want me to open and close the plate by hand carefully and see the signals by backprobing at the same time?
-> pin-3= ETC motor + should have 5v when the plaet is at closed position by default? or after its opened completely..got confuse with the "12v to close and to open wording"
-> Will calculate the total which shold be 5v.

6) The TPS test i will do it but i was focusing on APP sensor as to thinking its not sending its signal back to pcm which kind of works the same as total should be 5v like TPS sensor..so i was thinking its not sending signal back to pcm and pcm going in limp mode or something adn not starting at all..
-> I have the gas pedal with me here at home, shall i supply 5v to pin 1 and pin-6 on APP sensor at the pedal by a USB connector(5V/2A) supply and see if i see signals to be total 5v at all times regardless of the position of the gas pedal? I took the whole assembly out so i can press gas pedal myself with hand...

( Hope usb power supply's 2A won't be too much for the APP position sensor)

Thanks

1) TPS signal wires I didn't check since the plate do not move, so I went on with APP sensor if thats causing throttle plate not to open because it might be bad..So will install the new gas pedal as I ordered already and will check the signal reading at the pcm harness or backprobe the App sensor itself whichever is easier..

2) CNk or CAM issue, I wont be able to find it since torque pro needs to be set with custom pid's and I should enter specific data for chrsler cnk and cmp to show up on torque pro app...will search if i can find how to add cnk and CAM pid's for my car...if you know, would appreciate it too.

3) will watch the compression video online

4) ETC motor + or - do have nay voltage at default closed position...because its not coming from ECM. but here's the catch. when the car starts with the as pedal pressed...i can rev the engine for those 2 seconds, which indicates at that point the throttle plate is getting voltage...

5) I am gonna have to double check because the APP signal 2 gave me a battery voltage on first probe and 0 on second...thinking that the signal wire got shorted to battery voltage near the connectors c105 at lower dash on passenger seat...

6) I found this today, www.motor.com/magazine-summary/solving-t...-chrysler-ignitions/
This article seems to talk about the o2 heater circuits which are my current codes...in short its saying that the o2 sensors might be bad or shorted and its pulling the voltage down so the ignition system not getting enough power...
====================
In short, will try the scannerdanner compression test, install new gas pedal and check the App signal readings and see ff throttle works and does it start the car for the heck of it....will see online if i can get the data to create custom pid's for cnk and cam on torque app for chrysler.. if you know please let me know.

thanks

Iignore this blank post..