89 Chevy Silverado issues.

gonna send jr to the parts house after while. and get a MAP SENSOR. will confirm if it fixes it.

yes he has a little honda civic my bro in law gave him, but every man needs a truck. he could go pick dates up in it. some chicks like old trucks, that raw rumble , smell of burnt oil, they are roomy and manly trucks. that bench seat is good for hugging too. she caint be too fat though, if she is blocking the stick shift, you have to ride around in one gear. My wifes always trying to make excuses to drive my 94.. I tell her she cant handle the silverado,,, too much power. I keep my boat hooked to my 94. If I unhook it and bring it in the front, she will hop in that son of a gone and go. Like its a strong . loud wild horse shes wanting to ride ha it is loud dual exhaust, and puff a plume of smoke on start up, (lworn valve stem seals). love to see people reaction when at gas station and they are behind me, the hear VRROOOO, then the bluish black cloud drifts over thier car,, ha
My 94 runs super, and shifts like dream .

I ve heard the 95 1500s are problematic, my transmission mechanic told me they tried to make some changes that year that fell flat. not sure what else they did, with the engines and so on, but many people shy away from the 95 model year.

waiting on jr to bring the MAP sensor from the parts house, went out and took another voltage reading from the signal wire on the MAP, The air is cold and damp here today, the voltage is now fluctuating between 1.66 and almost 3 volts dc. when the voltage gets around 1.55 it is running ok, then the higher the voltage goes the lower the idle to almost shut down. its not a constant, duplicate surge today, its more of a high idle, less prominent surge, but easily heard.
Im thinking that some of the reason for changes in the way the truck runs may be due to when the truck is shut off, the computer resets to a base parameter, and then starts trying to compensate to a happy spot, or in my case compensate for a faulty sensor and incorrect voltage signal .

The computer uses the map for baro reading at key on and Wot. So if you’re climbing a mountain and it starts running crappy mash on it or pull over and key off. I would guess the map has priority but the computer is an if this than that device, meaning if I’m seeing this, than do that. Paul’s got a good video on it somewhere. For each voltage of each sensor there’s a programmed injector pulse width. The 95’ was the cross over year for obd2.some came with obd1 connectors some with 2 , but still read as obd1 and monitored more stuff. My 93’ had the electronic 4l60 already but not sure what they made for changes internally if any. I do know my 97’ burb has the newer 4L80e and it did have physical changes in those years. But you can always dummie them up with a carb and external trans controller.

the 8im working on is the 4 speed standard wIth OD . MY 94 has the 4L60E and when it was rebuilt, all of the weak parts were replaced, with improved heavy duty stuff. aluminum instead of plastic pistons, heavy duty OD CAGE, 5 gear pinion sprag , raybestos frictions. rebuilt valve body. new wiring harness. all new electricals , new converter, shift kit. I have a damned good tranny man. he explained to me, that the most important thing is hydraulic pressure integrity. many guy put the super duper red eagle alto frictions and a bunch of other stuff like high performance fluids, additives, ect, but all of that wont do any good if there is a pressure rise malfunction.. the clutches can only clamp as hard as the hydraulics make them, and if the valve body is worn, or the pump or gaskets, the new stuff will not last. He told me he could take a transmission that had worn bands and clutches, and put in a rebuilt pump, new seals and gaskets and valve body, and it would still last a very long time. the valves in the valve bodys can oscillate millions of times in a vehicle with 100.000 miles. when the circuits wear, they leak. same with the check balls, they spin, and can get flat spots in them and leak. the electrical solenoids cycle alot too, they can check good electrically but the pintles can wear and malfunction. Most shops dont rebuild transmissions, they put in the parts they think will fix it and hope for the best. actually rebuilding a transmission is quite extensive. removing and replacing all of the bushings is important too. the guy I have is like a transmission savant. if you met him on the street, you would think he couldnt walk and chew gum, but looks can be decieving. he works out of an old carridge barn from the 1900s , just an old shed, but he is one of the best transmission men in tx. im going to have him do the A500 in my dodge ram im pulling the motor and buying a rebuilt long block for it, . I have 5 trucks. an 89 dodge dakota shelby (only 1500 made), runs but needs trans rebuilt have owned it since 1993, . a 98 dodge ram, bought from my uncle because his floor in his house was rotten, and he didnt have any money to fix it, spun bearing, and transmission worn out has the 6 cylinder good for 300,000 miles if taken care of, )it wasnt)l ,. we did body work and painted it, so its next,, my 94 k1500, and wifes 05 nissan frontier. and of course the 89 scottsdale long bed.

anyway kif u ever go to get a transmission rebuilt, ask them whats the most important aspect of a transmission, if they dont say hydraulic pressure integrity,, RUN..

Map sensor has arrived, gone put it in right na.

whats Pauls you tube name or link,. thanks

Ok immediately after replacing the MAP; with a 50 .oo duralast the truck started idling great,, first slightly high idle then down to normal. took truck for a ride and check engine light came on. it threw a code 43. we drove home and took the air filter housing off and I noticed one if the pink wires going to the ignition coil was stretched tight over the EGR valve, possibly pulling on the connector and making a bad connection to the coil, we strapped the wire tight to the fuel line, after pulling some slack so it isnt pulling on the connector anymore. Im going to reset the computer and try starting the truck, it had a bit of a miss while driving and reviing at idle.
This truck has grabbed hold of me like a pit bull on a chihuahua. It simply refuses to leave me alone, like its been neglected so long, and it has somebody who is trying to fix it right, and it has attached itself to me, like a barnacle.
Its like every time I fix something, another issue pops up, like the truck has a gig list its feeding me.

Why did nt it throw a code 43 ev er before I replaced the MAP sensor, maybe the ECM is trying to relearn the sensors? I will disconnect the battery for a few minutes then try again. seems like it was very sluggish running around the block, like the timing is maybe stuck in base mode and not advancing. Yet before with a bad MAP sensor, it would surge at idle but run strong thru the gears. CRAZY...

ok after replacing the MAP sensor, it starts and idles fine cold, and after it starts to warm up, it goes into a steadily declining surge. not as pronounced as before. I looked under the truck and there is a sensor in front of the starter with no wire going to it, but on the opposite side, in the block up from the oil filter there is a sensor . I dont know if the truck had 2 knock sensors, or this is a different sensor.. there is a oil pressure switch with a cone around it near the oil filter, so I dont think it is an oil pressure switch.
the truck isnt throwing the code 43 right away, as I understand it does a test on every start cycle. I erased codes, ran it for abt a minute then rechecked for codes, it was clear. then I started it again and let it run. it seems like the idle surging got progressively worse. I read that the computer will keep either retarding or advancing the timing in 1 degree increments to attempt and cause an engine knock. so im thinking this could be the issue. I can take pics of the sensors in speaking of if needed. it looks like the wire going to the sensor on the opposite side of the block, was spliced in. it is seems it was done by someone who at least knows what shrink tubing is. so folks, it seems we have another scooby do mystery to solve. as I said my oil pressure sensor is near the oil filter, not near the distributor as many seem to be. the sensor in the block had to be for something but there is no wire that goes to it, or a wire nearby that isnt plugged in,, the sensor in the opposite side of the block from the sensor in front of the starter looks a bit different., it does have a large black rubber connector plug on it,.

when we bought the truck the ignition control relay was in a bucket along with other parts. it was on the bracket, but there was no MAP sensor with it. so that is what we had plugged in when it idled good. when we went to the junkyard to find out what part the green connector plug went to , we got the whole bracket with the Ignition control relay and MAP sensor on it. it seems like that is around when it didnt want to idle right anymore. so tommorow in going to put the Ignition control relay that was on it before, along with the new MAP sensor and see what it does.
attached is the part im speaking of. possibly the circuitry in it is different, I didnt pay attention to what year truck it came off of.
I tell ya I will never by a truck again where half the engine and electronics are missing and the other half have been installed in the wrong locations.
this is getting ridiculous,, the only reason I think there would be a second knock sensor is maybe they couldnt get the original one out, and removed a block drain, installed it on the other side, and spliced an extension wire to reach. they are only supposed to be torrqued to 14 ft pounds,. shouldnt be stuck in there.

STARTING TO SEE SOME PROGRESS. ! I put the original electronic spark module back on, and didnt see any improvement. when I stepped on the throttle it missed and backfired. now before that I replace the map sensor, and the surging went away at cold start up, it went to high idle just as it should but went back to a slower surge after it came off of high idle. abt that time the mailman came with the TPS sensor, I installed it and it changed everything. truck idles good and throttle is responsive. I cant say its 100 percent fixed because every now and then I get a little slight surge. I think what is now happening is when the truck sends the signal to check for knock and pinging, it gradually retards the timing in 1 degree intervals. once the knock sensor detects a knock, the computer take it out of the check for knock mode and continues with its program. Heres what I think may be going on at this point. I had put some high octane gas in the truck last time, thinking it would help out any stale residual gas still in the tank. I think the motor is having trouble creating a knock signal with that high octane gas, as I am reading that it is harder to light it off. if it takes the computer retarding the engine several timing adjustments to get the motor to ping and knock, that would show up in the idle quality.., the reason I believe this is when it goes into this little situation, the idle quality gets progressively worse each time, like its getting farther and farther away from its correct timing. I understand that the truck checks the knock system every start up. I dont know if it repeats it if it doesnt knock when it thinks it should. so im going to put some 87 octane in it, some and see if everything gets along good. I think that when the engine checks for knock, it is so subtle when the correct octane gas is in it, you dont really notice a stumble or surge.

Hey sounds like you got her licked,in a nice kinda way. I was out fighting the snow up here in a semi a couple days,couldn’t get back to ya right away. That round barnacle on the starter side should be the knock sensor. It should have a goofy looking cap kinda connector to the center of it. The other side I gotta look up and get back to ya. That picture is the knock sensor module aka spark timing module.

my book says some had 2 knock sensors, I dont know why they just had one hooked up, im going to test the one that is hooked up by banging on the block with a wrench while its idling, it should retard the timing a bit.
I cannot find any info on how the spark timing module works anywhere. Im thinking it must send the signal to the knock sensor thru the ecm. only a single wire on the knock sensor, so its output only, I think the ecm runs the program to retard the timing in one degree increments until the engine knocks, the sensor then sends a a.c voltage to the electronic spark sensor which may convert the signal to a dc voltage that lets the ecm know that the knock test either passed or failed. if passed computer goes back to its normal parameters, if failed check engine light. I have no check engine light coming on, so my sensor must be sensing a knock,, but with that 92 octane, it may be taking the timing quite a bit off the base, to make it knock, hence the little short term idle ramping episodes every now and then. . its been off all night, cold outside im going to go start it up and see what it does this morning.,

looking at the big picture this truck was quite the exception,, what are the chances of an engine having a stuck open thermostat, a bad MAP sensor, a bad TPS, THE o2 sensor in the wrong location, blown head gaskets all at the same time, but they were all problems.

Couldn’t find anything other than oil pressure and coolant temp on drivers side. When you say rubber connector, does it have three holes in it almost in a triangle shape? In a core plug hole(freeze plug)? If so it’s block heater. I’ve usually only seen them on the passengers side though, but I’m gonna put one on my drivers side as well when I change the lifters,just in case. In the negatives up here a lot.
The knock sensor gets checked at start up or near wot. The ecm wants to see 8 to 10 volts from the module all other times meaning no knock and other than the start up check,won’t use it below 900rpm. It mentions single blue wire from connector to sensor.dont run it near anything that would induce voltage, keep away from plug wires.

Now you know why you got it cheap. And those parts were in the bed. No telling what there thought process was,moving things or replacing parts with a found on the floor I think it’s good part.

yes I think whoever was working on it was a drunk or meth head,, crazy things like a bolt was missing for the control arm bushing on one side, and a nut off the other side. GOOD thing Im very attentive. those bolts dont just vibrate off, someone took them off, either forgot abt them or sabotage. Its the huge bolts and nut for the camber or castor adjustment .
what happens alot around here, every joe blow and thier brother goes to these COPART auctions. if they get something good, they flip it for good money, if not so good, they try to flip it for what they paid or a smidgion more. they just want to get rid of it because they dont have the space. they always have a big story with it, like its been in storage, wife got tired of it, someone stole car and took registration sticker off and plates. yada yada. they never get the vehicle registered in thier name, its still in the title holders name. Its not an easy task getting the truth out of people anymore. the guy who sold it to me delivered it, he dropped it off and hauled azz. like he was abt to have a digestive emergency.

Side note: I was looking to see if you had the same tsb’s I had on the 93’ and I didn’t find it but there was a tsb for false codes and I can’t remember the codes now,was like a 32 ad 47 or something,but anyway the fix is a new prom. The 93’ ran really rich with a slight pulse like idle, they used to have updated prom chips to fix this but I couldn’t find any. That’s how I found moates.net I was gonna run an emulator but sold the truck.

the truck came from oregon before it landed in Tejas, there is a blue wire going to the sensor, , and it has the big black connector going to it, where would the switch for a block heater normally be located, or do some have a plug? like on a regular house hold item, a lamp or vacuum cleaner?