ryxore

I have a 1988 Pontiac Firebird Formula. 305, tbi, automatic transmission

The car has major stalling/idle issues and a lack of power. It ran great until last year and it suddely died and had been giving me fits ever since I ran a bottle of Seafoam through it. The code was bad EGR, so I figured all the carbon from the Seafoam gunked it up. I tried cleaning it and then jsut replaced it. That didn't do it. I am getting codes 42 and 43 but I have replaced plugs, wires, cap/rotor and distributor as well as a long list of sensors. I will list everything that I have replaced, that I can think of anyway...

I have replaced, with new/reman parts from the store the following sensors, o2, air charge, coolant, idle air, pcv, egr, new alternator, changed tranny filter, radiator, new distributor, cap/rotor, plugs, wires, all new vac lines, rebuilt the entire throttle body, new front/rear brakes, new front brake hoses... all I can think right now off the top of my head.

I also set the timing but had some issues with that. I did unplug the ecu when setting the timing but the timing mark was all over the place. What I mean by that is it would jump or bounce back and forth from 0 to 6-8 degree's. If I idled it up to about 1000-1200 it would stead up. After the vehicle would run about 5 minutes it would steady out but as soon as I turned the dist. it would bounce around again for a few minutes. I finally let the car run while it was set at 0 and after 3-4 minutes it was steady. So I locked the dist. down and let the engine cool off.

Twenty minutes later, started it and it died, it will surge up to about 1200 rpm and then drop and sputter between 200 rpm and 800 rpm and die. If I give it some gas sometimes it will still die and other times I can keep the rpm's up around 1200-1500 and hold it steady for 2-3 minutes and it might come out of it.

I have checked for vac leaks using propane, cleaner, starter fluid and even a smoke machine (I rigged one up from walmart). I couldn't find anything leaking.

My brother-in-law is a mechanic and he hooked his computer up to the car last week. It showed a bad o2, which I replaced and the timing was at 20 degrees. So he loaned me his timing light and told me to fix the o2 then set the timing. He explained his timing light to me because it is a professional model, not like my $40 cheap-o from the local auto parts store.

Any help would be appreciated. I have tried everything I can think of and I have spent hours the last month or so on the message boards here and online trying to figure it out. I have tried everything I can think of or can find.

Thanks in advance for any help.

(I forgot to add that I removed the new plugs because I gapped them at 35, just like the book/car said to do but I found on the message boards here that I might want to gap them larger. So I have the plugs gapped at 40 now, although it made no difference.)

ryxore

I just got done checking the compression. All 8 were good but when I had the plugs out, which are brand new platinum plugs, they were all 'burnt' on one side. I am sure it is due to trying to set the timing and advancing it and retarding it so badly when trying to get it timed right. It is idling about 600-700 rpm now but it wants to die as soon as you shift into gear. The rpm's drop to about 100 or so then build back up to about 600. It isn't throwing any codes right now but I reset them last night. It was throwing 42 and 43. 43 is a consistant code it throws when it starts its stalling and bad idling fits. Which are inconsistent.

It will just randomly do it, sometimes when cold, sometimes after you have driven it to run a few errands. Other times I will run it 15-20 miles and when I get back in to leave after 15-20 minutes it acts up. It is very random and the check engine light only comes on when it is acting up. Once I clear the code it doesn't come back up until the next time it acts up.

Took the car for a test drive and it is still lagging real bad when you take off from a start. I am not talking about flooring it or anything, just a normal take off from a stop. It also died when I made a sharp, hard turn. It did it when I turned left hard so I tried it again making a right hand turn and it died again. The car started right back up.

ryxore

Did a little more so I thought I had better add it. I followed some instructions on here and reset the tps and iac... Still a no go.

ryxore

No one has any suggestions for me?

the-wizzard

hello,
please putt some answer's in here... I've got the same problems with my firebird 88

ryxore

What all have you tried? Maybe between us we can begin to eliminate issues. I's going to test the fuel pressure tonight... it is storming cats and dogs out right now though so I might have to hold off shortly.

Last night I started it up and instead of a nice steady idle it smoothy ran up and down from 500-1500rpm, even after I reved it up (thinking maybe it would smooth out and slow down.) I am thinking if the fuel pressure is good, then it is timing chain, intake manifold gasket or injectors. The injectors spray pattern look good so I doubt it is bad injectors. I did unplug one injector at a time to see if the car would run smoother, it wouldn't even start.