George Fuselier

I have a 1994 firebird with the lt1 engine the mods done to the car that I am aware of are as follows
cold air intake
mid-tube headers
eaton posi rear
3 inch exhaust with cat delete
electric water pump
3:73 gears
stock tune as far as i know
after market corvette wheels
audio system upgrade
adjustable gas shocks

the problems I am having is that the car runs rough from start up and gets progressively worse the longer it runs, it gets so bad it feels like its going to stall when I am in gear at a light and surges a little. It also smells like its running rich and sometimes backfires. This only started a few days ago. I do have the SES light on the dash but no code scanner available. This issue is driving me a little bit crazy since I am a first time firebird/lt1 owner and am in the dark about this problem I read about several things it could be including the coolant temperature sensor which I just replaced today, I bought new plug wires and replaced the four on the drivers side hoping it would fix the problem but I didn't change the plug wires on the passenger side yet. I have not pulled the plugs to see what they look like yet I was told that the car had been tuned up before I bought it last july since then I've put about 7k miles on it and done an oil change or two this is the most trouble I have had out of the car so far. And by the way before I forget It has 197000 miles on it. I am posting a short video below of what it sounds like

George Fuselier

update, changed the coil since the old one was corroded pretty bad, made an immediate difference in the way the car cold starts. still sputters and sounds like its missing, almost like an exhaust leak pop sound. this post has been here for only a day and over 100 people have viewed it yet i have only had 2 people even attempt to help on youtube comments for the video of the problem. i really need some help guys this is my main transportation and i have to use this to get to work and in a month the trip will double since i'm moving to a new location for work.

Mike.

iTrader: (1)

Well there's a lot of things that immediately come to mind. I see you have headers. Go over each one of the spark plug wires and see if any of them have come into contact with the headers and got burnt. You got the coil out of the way, what of the icm? You can have it tested for free at some auto parts stores. A big problem on these cars is the optispark distributor. It's not very water resistant and sits up underneath the water pump. Check the weep hole on the water pump and everything else around it and make sure there's nothing leaking on it. O2 sensors are also a possibility. It would help greatly if you could find a code reader.

George Fuselier

Had a code reader put on at a shop a high dollar scanner. No codes minus an A.I.R circuit code I don't have the exact code anymore. I did manage to pull a plug from the drivers side and the car definitely runs rich as a king so I am going to change them and if nothing improves I have found an optispark for a reasonable price on ebay new. I was a little confused because the sellers list the distributor as distributor cap and rotor but that isn't the distributor itself I saw a video on youtube about how the optispark was put together with the metal disk internally that has slits for the optical sensor to control the timing for the sparks to fire. The headers dont come in contact with the wires I have already bought a set of wires assuming that was the probl and changed the drivers side wires. The passangers side wires are routed the stock way away and under a heat shield below the headers. I am putting a pic of the header of the drivers side I habe no clue what brand it is. The substance on the valve covers that appeads white is the dried water and coolant from a hose that split a week ago that I replaced.

George Fuselier

Sorry for the typos I was using my smart phone and didn't check before posting

Mike.

iTrader: (1)

Do yourself a huge favor and don't buy a budget opti or rotor/cap. Most guys on here suggest a gm replacement. I went to oreilly and got their version with the lifetime warranty. I've gotten a new one twice now. It's not a part you want to be replacing multiple times.

I would definitely do the plugs. I don't quite like the look of that bolt in the header. Is it sealed well? Have you tightened up the bolts on your headers? Any leaks?