We bought a 1992 firebird with the 3.1 v-6 in it for our boy. Ran great, or as great as a3.1 with 186000 miles on could. Then the other day it started running really rough and would die if you gave it any gas at all then it turned over but wouldn't fire. So I changed the fuel filter and it would start but missed and would die if you gave it any gas at all. So I changed plugs and it seemed to cure it! But it missed and would die if you gave it gas again, later in the day. So I bought some more plugs to get it home, but when we went to get it he started it and fired right up and he drove it home. I let it run for about 30 45 minutes and it started acting up again. Its like its building to much pressure some where and its killing itself. A friend said something about a injector staying open and flooding itself out, but would it start and run fine the next day? I thought maybe the cat is clogged and builds to much pressure and kills it! But I just dont know, can anyone here have some advise??? Thank you in advance. And sorry so long.

 

I suggest doing a full tune up, especially replace the spark plug wires. a wet or rusted wire can cause a hell of a missfire. then i would check the timing, and then check for a vacuum leak. when was the last time you changed the air filter?

 

We just bought the car a week ago, so Im sure that it hasnt been changed in awhile. When you say tune up would you replace the cap and rotor also?

 

Ive got the same issue with my 3.1 Liter and its driving me crazy. Runs for 15 minutes great and then just cuts off even if you dont step on the gas. The next day it starts and runs great. Ive replaced O2 sensor, Map sensor, vaccum hoses, Coolant sensor plugs,cap,wires air filter,fuel filter. Puel pressure is 40psi and maintains 36-38 while running and we have spark after it dies. its driving me crazy!!! HELP!!!! FYI my car does not have the cat and the snap on scanner indicates the car goes back into open loop for some reason and thats when it starts running bad and dies.

 

Is threr a trottle sensor on this motor???

 

its your ignition coil dude..i bet 50 bucks its the coil. its called "the classic heated coil" sure it works fine but as soon as the coil discharges and charges like 7000 times, it over-heats and fails. but because the coil is failing, the ignition control module suffers big time too. they fight each other when one of the two has problems. just replace the coil, 20 bucks, and if you want get the ignition control module testd at autozone, when you reinstall the ignition control module in the dizzy, make sure you put a smear of "thermogrease" (special only for ignition control modules) under the ignition control module and make sure the bottom of the module touches the dizzy because that the ground for the componant. sorry to explain a lot, but i had problems once, just trying to help you get it done right. -mikey

remember the "igniton control module" and the Ignition coil" are two sepreate components.

 

ok In my case Module tested good. I havent replaced the coil, but would that cause the computer to go back to open loop? Or would it cause the injectors not to pulse? I have 40 psi Fuel pressure, but the 3/1 liters are a pain in the BUTT to pull the injector clip out and get the connector to test with a noid light. I think its an injector problem because the car will try to run with a few squirts of starting fluid

 

the tps, maf, and pickup coil (not ignition coil) help the Computer determine the injection pulse for the injectors. if when you say it goes back into open loop could be the o2 sensor not being heated up past 600F* Or the wire leading to the O2 sensor could be meltd. If the coolant sensor isnt above 64F* youll get open loop or, a broken wire to the coolant sensor could cause this, but again im guessing from what it sounds like is the o2 sensor isnt getting hot enough...also if you want try slaping the Maf sensor while the engine is running, if it surges the rpms could be dirty or malfunction but that doesnt sound like your problem. check the fuses for the injectors in the fuse block, and try flicking your finger at them and look for rpm surging. next check the ground wires that run to your injectors. lastly check the injectors ohms. because the computer goes back into closed loop, it ignores all sensors and runs on a default fuel map until the o2, coolant, and mat sensors heat up. (update) i just read you swappd out the o2 coolant sensors. my bad, um when you do the scanner is it a scanner and the fashiond wire. if after 15 minutes it dies, does it start up right away? could be the failing coil. do you got egr, and smog pump still. if you remove those then the chip gots to get programmed too. check those injectors and try vacuum testing the solenoid for the egr valve, the fuel evap canister, and try shaking the pcv valve to see if its operating ok. does when it die after 15 minutes does it start up right away??

 

Well I changed the coil, wires, plugs, cap and rotor, and checked the timing. Ran great. Then I go out this morning to start it and make sure it was running ok. Back to the old stuff!!! Runs ruff and feels like its got a bad miss, idles ok but if you go to give it gas it falls on its face and wants to die. What the heck is up????

 

did you replace the pickup coil with your minor dizzy rebuild. sounds like like the ignition control module could be failing too. are the plugs gaped to specs. and also try taking a like a rubber hose or something like a makeshift stethoscope and try to listen to the injector pulse. has to be something electrical or maybe a dying fuel pump, try turning the key to on position and push the schrader valve on the fuel rail under the hood to see it squirts out under high pressure, if it dribbles it could be the pump's check valve or bad pump. you can even apply 12volt power to the G terminal on the diagnostic link under the dash to see if it can runn constantly with out hickcups (makes that noise brrrrrr) last check the MAF sensor by slapping it. (im not sure if V6 has maf sensor, its located in the intake ducting right after the airbox filter and b4 the throttle body. if when you slap the maf, and it happens to surge, then the maf is bad or dirty. r you getting engine codes...try to see if there are any codes.

 

In my case the car will not start till it is cool again, it will try to restart but just sputters and chugs then dies. If I attempt to start it again all i get is cranking and no start. I still have the EGR and smog pump, id like to rip them out... but havent yet. PCV was just changed. I though the car ran in open look till it was warmed up then closed loop took over. MAP is new, no codes on scan tool and fuel pressure is 42 psi and when running drops slightly but holds pressure at 38 psi.

 

try replacing the pickup coil. thats the only other thing i can think of. its runs only when cool? got to say thats a tough one. did you test the pickup coil? ohms

 

In my GM service manual it says in order to test if the ECM is seeing the reference signal and controlling the injectors, you can use the 4 way injector connector by using a test light between terminals B & F and A & E and if the test light blinks while cranking the ECM should be considered ok. Well There is a plug at the top of the engine right behind the AC compressor with 6 wires, that looks like it leads to the injectors. So I unplugged it and not knowing where the B and F or A and E terminals are I tested all of them and get a steady light which directs me to another part of the flo chart to test the resistance across those. Im not sure where the connector is and where those specific terminals are. I cant find a diagram.

Help!

 

wow you got the third gen bible "service manual". where would one get one. and im pretty sure your injectors are cool..

 

do you know where that connector is so I can test the resistance?

 

my car does something like this mostly at night ill b crusing along about 70 and itll just cut out and pick back up and cut out agian and when i stomp the gas it blows a big flame out the pipes and i just bought a new distributor bout a moth or 2 ago