Engine shut down

Satrts fine, seems to stall more often during the heat of the day, some of the longest drive times ive had without stalling is when its been at night. There are no error codes being given during the event, before or after, nothing. By accident one time while filling the radiator the hose slipped from my hands and sprayed water all over the ignition control module (while the truck had just stalled minutes before) I went and it started right up, I let it run and waited for it to stall again, I then sprayed the ICM and waalaah it fired up. I repeated that process like 6 times so I thought I got it, its the ICM. NOPE, wrong, I changed it out with a new AC Delco OEM ICM, still stalls. So lets cover what I have replaced all new all OEM. Fuel Pump, Fuel Filter, Oil Pressure Sensor, Engine Coolant Temperature sensor, Ignition Control Module, Thermostat, New Spark Plugs, Checked and cleaned grounding wires, Air Intake Sensor. Question could a clogged or damaged Catalytic converter cause these problems? If so could I just pull the o2 sensor to determine if that was the case? Cuz I did do that also. What about a crankcase Position Sensor? Could that be causing this nightmare? I am at my end I need this truck for work, and its absolutely killing me not being able to track this problem down. What about the PCM? Anything any suggestions, I mean anything

You are right on the money my man, I didnt read your response until I just got home after I went and looked at the crankcase position sensor and it was gummed up and all sorts of nasty. I replaced it and vroooom, I drove 145 miles today no stalling. You are the only person to say, "the crankcase position sensor is "heat" sensitive. I have asked like 5 others should I be looking at that, and they said yes maybe but check this first, then id be going down a different road. But yes you are correct sir, it was the crankcase position sensor that was making my 1996 GMC Sonoma 2 wheel drive 2.2. L 4 cylinder truck stall intermittently. (I think I spelled intermittently correct) who cares the damn thing runs. MUAH.

I have a 1995 gmc sonoma that will start and then die almost right away. It will do this over and over eventually it will start. When it does start it barely runs for a few seconds and then runs fine. It runs fine while driving. Also It has a vaccumn leak in the a/c system that I need to fix because the vents have lost control(i don't know if this is part of the problem). Also the ignition module was replaced about 2 weeks ago because I thought this may be the cause of the problem. Once the engine is hot and warmed up it starts right up.

Yeh sorry I forgot to put all the info. Its a 4.3 with cpi injection vin w. The fuel pressure is fine I checked that its about 57 psi and I replaced the filter sometime later last year so it is fairly new. Also last year I replaced the crank sensor the cam sensor and the catalytic converter is fairly new with about 30,000 miles on it so it probably has nothing to do with them.

I think I may have solved the problem. GM has a service bulletin out for hard to start and rough idle on start up. The bulletin says that one ore more of the poppet nozzles in the spider injector may be sticking. I have run marvel oil along with lucas oils tune up in a bottle through the truck and it hasnt had the problem. Is it possible that this is the problem? However that may be because it has been warmer here lately, I bought a coolant temperature sensor because it was only 10 bucks so I figure it can't hurt to just replace it. With my luck though I will probably be back

Ok all of that seems to have solved the problem. I have one more problem to ask about. The truck has had a problem with the fuel pump relay for some time. Occasionally the fuel pump will not work. If yo smack the relay a bit it will start working again. The relay has been replaced. At one time the relay would make a buzzing sound. Is this due to a bad ground? If so which contact on the relay block wiuld I need to repair the ground on. The relay block has constant power to it on the bottom right contact point. Ant it has power to the top right when the ignition switch is turned. The center right contact has no power or ground so I assume this is a wire run to the ecu. The two far left contacts have a ground but I believe one of them is faulty which would I need to repair?

New head, idle control valve, pcv, runs great when running, no power loss, no noises, cuts out when it reaches about 100 degrees or 2-3 min from a cold start. Its very sporadic after that, it will do it anytime, any rpm range, but if im on the highway it wont completely die. It just cuts out, and I lose everything for a second and then get it back. Please help.

Thank you for all of your help. I ran Marvel Mystery trough the Fuel system. Tuned it up just changed the fuel filter the plugs and wires changed the air filter and fixed the vaccumn leak and changed the temperature sensor. It has never run or idled better. Haha it seems I have a never ending list of problems when I was scanning for codes it pulled p1864, p1886, p0753 and p0758 I know these are transmission codes and have to do with the shift solenoids. Do you have any tips or suggestions on how to solve the problems?

Wait like your truck just dies randomly? If so that almost sounds like a fuel pressure problem. I have a few tests for that.

1. Make sure fuel pump runs
If running:
2. Remove quick disconnect from fuel filter, let fuel drain out, reconnect the line, and turn key to ignition(turning fuel pump on). Then check that line again, fuel should come out. Also check your Fuel Pressure Regulator located near cylinder 1, opposite of plug. Remove the little line(be careful they are hard plastic lines!) When you try to start no fuel should come out. (Fuel coming out means FPR is broken)

Try to hit back with some more info ill try to help u out. I got a 97 sonoma with a hell of a lot of problems. My post is 97 sonoma. :P

Oh and the cutting out, does that only happen in neutral? Or while you are still in gear? Mine cuts out in neutral for about the first 1-5mins UNTIL it is warm im gonna replace my IAC sensore see if that helps me any.

Hey before you do IAC or Idle Control Valve, I just tested my ICM Ignition Control Module at the parts store and it was bad. Its underneath the coil packs on the 2.2 L easist to take off whole thing (3 bolts for the ICM and coil packs attached to it). Typically goes bad about 100,000 miles or more when dielectric grease dries up between ICM and mounting Plate. Sorry it took this long, I'll try to check back sooner.

Wait did you find out the problem to your rough idel/ instant dying?

I have a 4cyl sonoma with exact same problem. I replaced so much stuff on it, I was told it sounds like a IAC sensor which may sound about right. But I just got done doing cylinder head. I have no clue what the problem is with this thing, but like you said it will die right away, and once its warm has virtually no problem. I thought origionally O2 sensor but that throws a engine code(which I dont have showing).

Post back on my 97 sonoma. With the solution to your starting problem.

Much appreciated man

What exactly have you replaced? Mine just needed a tune up it was just a whole bunch of little things. Does your 4 cyl have a distributor ignition system. If so you may want to check the timing as it could be slightly off

As for your fuel pump. I replaced my fuel pump (4cyl 2.2l sonoma), and inside the new pump box there was a note to replace one of the connectors to th e fuel pump because GM said " It tends to lose connection and arc back and forth, thus causing the plug to melt itself to the fuel assembly--big problem.) That may be your problem.

This happens with every time, worse when colder outside.
1) Start Vehicle and warm up for about 1 minute
2) Put vehicle into gear and idle drops way down then comes back up
3) Leave then approach a stop, about 1 mile away
4) When braking to a stop, when almost stopped, idle surges way up (dangerous)
5) Idle cycles up and down gradually stabilizing
6) As engine warms up, this effect gradually goes away

1) This problem is not related to EGR valve, as it has been replaced and cleaned many times without ever changing above symptoms
2) This problem has occured for many years
3) Definately worse with cold outside temperature
4) Seems like computer thinks outside temperature is much warmer than it really is

Any ideas?