[FIXED] 2003 Saturn l200 high ideal

Hello,
Im Cris, i watch lot off videos, throw scannerdanner, they great! i just confused on the this car, i have service codes, p0105,p0107,p123,
map senor problems, and high idle voltage on tps, this could be little long, explaining what ive done so far: saturn wont shift,but in 2nd gear, i have no service codes 4 transmission!! i bought myself a verus, because save money on repairing my own vechicle, it gives great detail whats going on, do test. i went to the transmission section, went throw the test turn in on all the seleniod, comferm they were working,transmission reads the tps information some how?

the saturn has high idle, turn it on it runs up to 3000, then goes down idles at 1900, so i bought a new tps, thinking it was bad! i check it had 5 volt supple, i used a light tester, to verify good ground be puting one end on positive, & toughing the ground on plug end 4 tps, it light up, i used the volt meter to test the signal wire, unplugged test if there was voltage on signal wire unplugged, there wasn't. so i mounted tps on throttle body, plugged it in, back probed the plug in, conform it had 5 volts.i back probed the signal wire with key on, the voltage in closed throttle is 4.3 volts???????

i replaced the map sensor 7 months ago, i found that the iac controls the idle, so i put a new one in, didn't change, ive sprayed the intake with carb cleaner to see if it leaking, didn't change idle, so not leaking, i sanded 3 ground point, grounds, one under intake, one connecting block to head, one one fender back by firewall, thinking computer messing up because bad ground?? nothing ive done so far changes idle, to normal,still idle really high!! i looked at wire diagram back tracked the signal wire , ground 4 tsp to computer think it good??? the scanner says idles at 99%, 4.3 volts closed throttle on tsp, shows no readings for sht,or long term trim , im trying to show u the scanner readings off data,
Computer problem????? im not master mechanic, i just learn as i go, try figure out how to fix vehicles!! forgot to mention i have a code 4 ac relay?? too, dont know if that would affect the voltage off tps, closed trottle,or idle problems?

cant load pics??
so write data

RPM 3301/////// TPS V 4.35
TPS% 99/////// Coolant 185
intake air (F) 71////// HO2B1 S1 mv 977
HO2S B1 mi 846 ///// INJ1 CMD 4.26
INJ 2 CMI ms 4.27 /////// INJ 3 CMD 4.26
INJ 4 CMI mvs 4.27////// Lean Rich Trans 0
LN Rich AVG 0 ////// AF ration 12.9.1
OPEN Loop///// ST Trim % 0
LT TRIM% 0 ////// FT Cell 22
MAp IN hg 9.1 ///// Map (V) 1.08
BARO inhg 22.4 ///// Airflow GM/sec 20.32
IAC postion 121 ///// Desired idle 763

Id appreciate all insight ,suggestions , thanks 4 looking !!!


update computer didnt fix it 60.00 wasted!!!
codes 105 map or baro pressure circuit problem
code p0300 engine misfire, it cylinder 3
po530 AC Refrigerant pressure sensor circuit

i may fail at fixing!! but dont give up!!!! more research.lol

Whoa, that TPS is WAY too high for idle. :silly:

You're certain that the TPS signal wire showed zero on the scanner with the TPS unplugged? If so, then I think my first suggestion would be to leave it unplugged and see if the idle gets any better. With any luck, the PCM will go to a backup strategy and rely on the MAP signal instead.

These sensors are pretty simple, so I doubt it's an installation issue. Can you do some more voltage measurements for me? KOEO, with the TPS plugged in, backprobe all three wires and tell me the voltages.

Thanks 4 ur advice!
This what I know, voltage with tps unplugged is 5 volts, believe ground is good, the signal wire shows no voltage, new tps, but when I plug it in yes get 5 volts,ground, but signal wire says around 4.3 volts??? Closed throttle???
Vehicle running plug & unplug tps doesn't affect idle, no difference in idle?? Plugged in or not????

What is the voltage on the signal wire at full throttle ? --- thinking wiring reversed

Kinda what I was thinking, Andy.

but when I plug it in yes get 5 volts,ground, but signal wire says around 4.3 volts???

Thanks for getting back to me on that one. Kinda like what Andy was saying, if you sweep the throttle, how does the signal voltage respond?

what does a multimeter read when pierced or backprobed at the signal wire? vs what the scanner reads?

Hello,
Its little cold out side,so not working on it much, the voltage drops when increase throttle to 1/2volt, the gray wire has 5 volts like suppose to,

I read that if code 105 is present,it could be short to voltage on 5 volt reference ,if shorted then scan too will show throttle is at 20 to 30%,at closed throttle,mine says 97% know, & ac pressure sensor is 2.4 volts with AC off, & fuel tank pressure voltage is over 4 volts,

I haven't checked voltage yet at ac pressure sensor to see voltage, maybe short to volt some where??? Not sure??? Trial & error.lol the verus days it at 4.3 volts same as multimeter

CCordell wrote: Hello,
Its little cold out side,so not working on it much, the voltage drops when increase throttle to 1/2volt, the gray wire has 5 volts like suppose to

The TPS is working backwards. :blink: It should be closer to .5-1.0V at idle, not WOT.

Do you recall the wire colors, and their voltage readings? 'Cause either the TPS itself was manufactured incorrectly, or the sensor is wired wrong. This is the OE wiring diagram for the TPS:



What is the MAP reading at idle? I'd be tempted to ignore the MAP code for now - it's possible that code is setting because the PCM is using rationality logic by comparing the MAP to the TPS. Right now, your TPS is showing wide open, while the MAP is probably showing closer to idle, and the PCM doesn't know who to believe. :silly:

hello,
Thanks 4 ur information!!! This is what scanner says
Tps. 97%
Tank pressure volt 2.69
AC Hi side V 4.27 AC off
AC Hi size psi 384.2
CC brake sw open
AC rly open/short yes
Tps voltage. 4.27
Engine load 99%
This is key on engine off
Coolant 23

The tsp & AC high sides has same v = 4.27???
I put 3 different tsp in know, all had same readings 4.3 v closed throttle, they gray wire, has 5 volts unplugged, red wire signal wire, black 4 ground.

Yeah, that A/C pressure sensor is way high, too. :blink: I just checked the diagram, and they don't share any wiring outside of the PCM.

I put 3 different tsp in know, all had same readings 4.3 v closed throttle, they gray wire, has 5 volts unplugged, red wire signal wire, black 4 ground

The ground has 4.00V on it? If that's true, then you're looking at the issue.

hello,
I cut red signal wire,on the tps, to see what it says before going to computer, it said .4.3 volts
I thought that 3 sensors run off one 5 volt ref from computer? Map senior has separate 5volt ref from computer, guess checked for good ground, don't believe there was voltage on ground wire??? Dont remember?
If short,they should read voltage leaking on ground wire??? Im not master learning as I good!! Lol

Would you mind doing a recheck of the the three TPS wires, KOEO, when you can? Because that 4.0V on the black wire is a big red flag if it's true. The fact that two of the 5V ref sensors are showing similar voltages would point towards a PCM ground problem, or possible harness damage.

I thought that 3 sensors run off one 5 volt ref from computer?

You're correct, they do. But earlier, you posted some readings that showed the MAP at just over 1V, so I don't believe the 5V reference is shorted anywhere. Because the signal voltages are high on the TPS and A/C pressure sensor, the grounds are more suspect.

[thanks 4 ur information!!
Guess got check grounds? I did sand 3 grounds one under intake,one of head to vale cover, & one on driver, fender. Engine, firewall, didn't comferm where computer ground is yet!!!
& go throw thev ac pressure sensor & tps wires looking shorts in wiring? Lol I don't like wiring problems.lol but got fix it!!!

Thanks 4,ur help

No worries, we can handle a wiring problem if it comes to that. If it's true that the ground has 4.0V on it, then we may try adding a jumper wire to ground to see if we're headed in the right direction.

OK cool,
It going get colder outside & snow here,so might be little while before I work on it again,

Thanks!!!!

does the ground light a test light?? compare the brightness to battery negative to compare what a good ground looks like vs the suspect ground t the tps

In not 100% all wires test, I took light tester, clamped it on positive post on batter, touched the ground wire& it light up green light, or
volt meter, put red lead on positive battery post, touch wire ground wire , it read battery voltage.
When I test positive wire test light turn red, instead off green.

Got learn how to do drop test, test wires good or not!!!

I haven't compared brightness off ground on tps , & brightness off ground on battery, but will

Thanks

Thanks 4 everyone's help!! It running & shifting know happy!!! Its my fault!! I checked the plug ends on the tsp & ac pressure sensor, they have same plug end!!!
I bought car had whole in block, replaced engine painted it, I put the ac sensor wire on the tsp, looked at them, switched them & it works fine!!! Live & learn!!!

It drove around 4 yr like that!! Switched plugs wires,ends thanks 4 everbodies help, appreciate all!!

CCordell wrote: Thanks 4 everyone's help!! It running & shifting know happy!!! Its my fault!! I checked the plug ends on the tsp & ac pressure sensor, they have same plug end!!!
I bought car had whole in block, replaced engine painted it, I put the ac sensor wire on the tsp, looked at them, switched them & it works fine!!! Live & learn!!!

It drove around 4 yr like that!! Switched plugs wires,ends thanks 4 everbodies help, appreciate all!!

:lol: Well done, sir! I suspect that the 5V and signal wire pins are reversed on the TPS and A/C pressure sensor, so that's why they generated inverted signals. Seriously, great job catching that.

Honestly, something you said earlier caught my eye...

I put 3 different tsp in know, all had same readings 4.3 v closed throttle, they gray wire, has 5 volts unplugged, red wire signal wire, black 4 ground.

I wondered why you said the signal wire was red, 'cause the diagram says it should be dark blue. :huh: But I let it go, figuring someone had installed a replacement pigtail at some point. Shoulda caught that earlier. :blush: It didn't help that the A/C pressure sensor was on a separate wiring diagram.