I am at my wits end with this 89 iroc that Ive restored! I have been working on it for the last two years and have gone over the entire car, paint, glass , brakes etc. When i first got the car it ran fine but did have a check engine light on (maf which I replaced and cleared) no light on now but the car runs rougher than heck and often dies at idle. when it does that it will re start (but hard) and then as soon as you touch the gas will die again. I have new plugs and wires. And now I noticed that the gas gauge is pegged beyond full, and I know is was working and this just occured...relayded maybe????thanks much!!!!!

It sounds like maybe your fuel pump is bad. Did you replace the pump when you restored the car?

thanks for the repliy.....no I did not replace the fuel pump.....but this problem came on suddenly and does it in both open and closed loop, although it doesnt die in open loop......also I failed to mention that it seems to be running awfully rich....

Did you check out all the trouble codes before clearing the ECM? A code 45 indicates rich exhaust, which should of come up. What trouble code did the ECM kick out for the MAF sensor? I'm looking in my book and it shows a code 33/34 up until 1987. I'm wondering if you might have a bad O2 sensor. Do a systems check to see if there are any more trouble codes stored in the ECM. Drive the car around a bit (If you can) then check for codes.

I dont recall the code number, but when I looked it up in the book it said MAF sensor. I wanna say it was 44. Also my bow tie buddy up the street said it sounds like fuel pump relay....do you know where its located? thanks in advance

The fuel pump relay is located on the firewall just to the right of the power booster. If you have three relays side by side, it is the one in the middle. If you have just two there, it's the one on the right.

thanks again! while fooling around with the darn thing I dug the wiring schmatics out as the check engine lite came back on, code 33 Maf sensor again! I checked the sensor and discovered no voltage. On to the maf power relay, also to the left of the booster there was voltage,but..........coil would apply but not close......five bucks later problem solved! hope this might help anybody with similar grief!!!

i have a 84 camaro with a 305 and i had my carb changed to a holly and my distributer and now my torque converter will not lock up in over drive

I encountered a code 33 on a buddies car. What I found was that the terminals on the vehicle wiring harness for the MAF had lost their tension and were a bit corroded. A tighly wound piece of sand paper scuffed off the tarnish. A pick probe was used to retension the socket pins. A little dielectric grease helped prevent further corrosion. All the MAF codes went away. In my case, it was on a 97.

I'm having exactly the same problem your having, for the last 2 weeks I'd be driving say 55 mph and all the sudden the engine isn't running.. I'd coast for about 5 seconds and then the engine IS running again and power comes back. I have been trying to figure it out in my off time but im working tons so its hard.

Today I got my slap in the face, I was crusing down the street got to a light at a VERY busy intersection, it died but i was almost last in line so I motioned to go around me. I got it started and it drove 30 feet and parked it for 10 minutes although I knew already at this point it had nothing to do with heat.

It starts up very easily so I think I'm alright, I pull out of the place and pass 5 cops >_> get to the next intersection where I need to make a left. Dead. It starts runs for 1 second, dies. Again I'm at another gigantic intersection so I push it through the red lighted intersection (thank god I'm in my orange construction worker gear still). I immediately go for the fuel pump relay, I remove it, clean it, the harness wires look iffy so I cram them in a bit.

I crank the engine for 25 continuous seconds and then boom for no reason at all it starts, and dies. I crank it again and it starts ok but its missing BADLY.

I couldn't keep it running with anything less than 1500 rpms and it sounded like a freaking harley bike. I kept at it for 2 minutes and the idle smoothed out with very occational jumps here and there.

I could feel it was 'off' so I powerbraked it all the way home keeping it at about 1100 rpms (this by the way makes it VERY hard to stop :D)

The fuel pump seems to be working whenever I ignition on though.. I am having the worst luck figuring this one out.

Things I've replaced trying to solve this in the last few months
Coil
Wires/plugs
Cap&Rotor
Ignition module on distributor
-swapped back and forth my msd 6al with no luck-

I'm thinking it might be the computer but I was hoping you guys might know something more obvious

Always true since I got the car are:
Runs super rich
Idle never very smooth
No engine codes

in the aftermarket segment its an msd coil and 6al ignition w/ shorty headers and no knock sensor.. (dont ask)

computer seemed to be already non stock and there's a hypertech chip i added...

I'd appreciate any thoughts, also it might help with dak's iroc cause these computer controlled monsters are too complex


Edit: Oh I forgot to mention, the problem started 6 months ago as seveer hesitation on bumps and other bad road imperfections while at WOT only.. wtf eh?