My 1989 Firebird formula 350 starts missing after it gets warm it runs perfect while it is cold. It was giving me a O2 sensor that is rich code I replaced the sensor and it still misses. Everything is stock but it puts off a smell of rotton gas while it is running and missing. I have replaced the O2 sensor, a fuel pump, spark plug wires, Distributor cap and rotor button, and plugs and fuel filter. It has new 93 octane gas. I just cant figure this out motor has less than 10,000 miles on it. It is fresh. Lost its power after it get warm and shakes bad.

 

Sounds like u covered everything except the coil its self where the spark comes from as everything warms up resistence is gained if your coil is going bad/weak it would give u those symptoms

 

i am having a similar problem. when my car gets up to temp if u floor it it bogs,cuts out at like 3000 rpm the jumps to 4 then cuts out then snaps back to 5000.. an as the car gets hotter closer to 220 bogs pretty much all the time then eventually shuts off. im a looking into it it now ill let u know what i find maybe it will help you. and i am starting with the coil an dizzy as well.

 

I will replace that today thankyou I purchased a stage 3 computer chip for the car thinking the computer might be the issue but I didnt think about the coil itself thankyou I will try that.

 

I replaced the the ignition coil and the ECM and it still has the same problem it just runs terrible when it warms up I really dont understand

 

I am having the same problem with my 1988 trans am with TPI. runs great when cold then starts missing and sputtering when it gets hot. It is really a pain in the rear. Any help would be appreciated. I was going to replace the coil but I do not have money to waste.

 

Have you OHM checked your injs while hot?? You could have one shorted/sticking open.. Also check the vac line on your fuel psi regulator for fuel.. shudnt b any in the line.

 

Any of you guys checked ignition control module, or dist pickup coil?

Rotten egg gas smell - never encounter this really anymore these days, but is this caused by using regular leaded petrol with a cat? I remember plenty of cars smelling like this when cats first arrived en-masse.

 

Ohm your injectors, I had the exact same problem and that was the cause, 6 or 7 were bad

-Jim

 

sounds like it may be a bad ignition module, they get weak when they get hot. a clogged cat can cause a rotten smell in my experience.

 

what are the injectors suppose to Ohm at or what number am i looking for i appriciate your help
Charlie

 

I replaced my ignition coil, pick up coil, and the module inside the distributor. Do you know what the fuel injectors suppose to ohm at when they are warm or ohm at

 

They should be around 16, and within 10% of each other. Post up your numbers afterwards.

 

this is the numbers that i got when i Ohmed the injectors.
1-18.0
3-17.9
5-22.2
7-13.1
2-14.3
4-18.3
6-5.1
8-14.6
they are the stock original injectors that came in the car when it was new they have never been changed.

 

hot number are
1=18.1
3=17.6
5=20.9
7=12.3
2=14.6
4=19.8
6=3.2
8=13.3
that the hot injector ohm numbers
Charlie

 

Time 4 new injectors..

 

Yup, make sure you get bosch our the new style ls1 injectors. Depends if you want to keep the original look or not.

-Jim