I have an 89 305 TPI 5 speed Iroc. Here's whats going on... The car cranks and starts everytime you attempt to start the car. Within about 1-2 seconds after it cranks over, it dies. This just started happening about 2 weeks ago and I can't find the culprit. I have good fuel (45 lbs. at the rail), spark, and air. I've changed the computer and the ignition module with no fix. It runs when I spray starting fluid through the TB but dies as soon as I stop sraying starter fluid. Could VATS be causing this? Any help would be great.

 

Please.... Anybody.

 

Does the fuel pump come back on after it has primed and the car starts? It could just be priming then it runs out of fuel. Do you get good oil pressure when it starts? i the oil pressure sensor is bad it could stop the fuel pump from coming on through the the fuel pump relay.

If you are sure you have good oil pressure then run a jumper wire on the relay that allow the pump the run constantly and see if the car will stay running.

 

I have never been a real fan of using starter fluid in Fuel Injected Engines. When you turn the key on do you hear the fuel pump come on for roughly 5 seconds? You might also hear it run after a unsuccessful start. Does your car have a Mass Air Flow or MAP Sensor? Find out which one you have and ensure the electrical connections are good. If it is a MAP Sensor ensure the vacuum line is plugged in also. The next thing if you are running a map sensor would to be replace with another 1 bar map sensor.

 

The fuel pump primes before I start the car and I hear the fuel pump run for about 2 seconds after the car dies. I have by-passed the oil pressure switch to make the fuel pump run constantly... no change. I have a MAF sensor and the connections seem to be fine and I have tried to start the car with the MAF sensor plugged in and un-plugged. Keep the ideas comming because I can't find a post that has a fix for this yet. Thanks for the ideas so far.

 

does the engine flood out? how long after it dies does it fire right upor do you have to crank and crank? Try unplugging the fuel pump from the plug in fron of the fuel tank should be a duesch plug. mine wont run with the fuel pump plugged in but idles fine with out it and i havnt found the culprit, so im swapping for a carb setup.

 

It does not flood and it's not flooded (checked the plugs, look good). After it dies, I can crank it and it will start up immediatly but it dies again within 2 seconds. I know what connector your talking about for the fuel pump (already replaced that) but I don't understand how unpluging the power from the pump would make the car run.

 

Does anyone else have any other ideas? I have a scanner and I can do a capture mode for the 2 seconds the car is on and post the information if that would help. Here's what I know so far.
1. Ignition Module (good)
2. Fuel pressure (45 PSI and holds)
3. New fuel pump relay and pump
4. IAC (good)
5. TPS (set up correctly)
6. Timing (correct 6 deg.)
7. New button in distributor
8. New coil
9. Injectors (350 size on a 305. All OHM at 16.9)
10. New FPR
11. New ECM
12. New clutch (Doubt this has anything to do with my problem)

About out of money and deffinetly out of ideas.

 

Hi
It sounds like a fuel issue because you stated that spraying it with Starter fluid it keeps it running. So it can’t be anything to do with ignition system because it would shut down quickly. Have you checked the ignition switch because there are two positions, Start and run? I assume when you had it running and spraying with Starter Fluid, the switch was in the run position, not the start position. Also I am assuming that you have the fuel pressure gauge hooked up all time and monitor the fuel pressure when it started and tried running – it was good all the time?

I think if it was the VATS, the car would not start at all but I will check my shop manuals tonight (87 and 92 Camaro books). My 87 Z-28 will not run if the MAP sensor is disconnected – make sure it is connected and working. One thing I did not see is there any Fail codes?? Sorry I could help you more but maybe there are some ideas here to have you recheck.
Thanks
Bill

 

I thought maybe it could be the ignition switch. I bought one today to see if it works. I do have the fuel pressure gauge hooked up all the time and I am constantly monitoring the pressure. It's basically 45 PSI. I noticed you said your 87 won't run with the MAP sensor disconnected, mine is an 89 and I only have the MAF sensor. Also, I do not have any fail codes (checked for that plenty of times. Everytime I start the car I have the fuel pressure gauge hooked up and my AUTOXRAY 6000 hooked up, monitoring engine vitals. I'll let you know if the ignition switch fixes the problem after I put it in tonight. Thanks for the ideas Bill.

 

How about the oil pressure switch? The switch could be bad... Do you have adequate oil in the crankcase? Also try taking your vats key and rub the "chip" with something like 1000 grit or greater sandpaper. Maybe 2000 grit would be better. I had a friend with a VATS Cadillac, and his key was the culprit until we bypassed the VATS altogether. Write me to find out how to do this... Relatively simple. (about a 6 on a scale 1 to 11.) His key was ultimately too THin for the resistor to make contact inside the lock cylinder...

Scott AKA Yeah Low

 

I replaced the Ignition Switch with no change. Car still starts but dies immediatly after. I do have oil pressure and I can jump the wires to make the fuel pump come on consistantly so I'm pretty sure thats not the problem. As for the key, I had a new one cut with the proper resistor in it. I've also heard that if VATS goes out, the car will not even crank. Mine starts but dies so I don't think this is VATS related. Anymore ideas would be great.

 

Hi Folks
First my 87 has a MAF - typo - sorry. I looked at my shop manual and here are some of the areas to look at - some surprised me. EGR valve sticking open – most cases the car will not start. Fouled plugs, defective cold start circuit (don’t know if the later models had this), defective MAF sensor may cause a no start or stall after start. Also water contaminated fuel – also check both injector fuses. I don’t know what to tell you after this.
Thanks
Bill

 

Great news everyone..... I found out what the problem was and my car is running like a dream. MAF sensor was bad. I unplugged, started the car and it ran (like crap) but it ran. Hooked the sensor back up and it died right after it started. Bought a new MAF sensor and I'm back in business. Thanks for all of the help and the ideas.