my car has been getting 11 miles to the gallon lately. i mostly only do city driving but 11 is still horrible. cars with 500hp get way better mileage than that (besides the viper).

problems.
very old plugs replaced soon
MSD wires soon
SES light comes on periodically for short periods of time?
MSD ignition this summer

my only suspicion is that the plugs are horrible and that possible the optispark is messed up? tell you the truth i dont even know what the thing does, but it sounds like spark :-p I know the headers can throw off the sensors so that could be the SES problem. i guess maybe i just need a tune real bad?

see sig for car and mods

 

Could be a bad MAP sensor. That would explain the SES problem. One sure fire way to check for that is by removing the MAF plug and running the car. If the vehicle will not run then, thats your answer. The vehicle must have a working MAP sensor in order to run in Speed Density mode. (i.e. when you unplug the MAF). Try to let it sit for awhile, or drive it for a day without it plugged in. If you have a lot of random stalls then you have a bad MAP.

If that is not your problem then you more than likely have a vacuum leak or bad O2's. I would scan the car before taking too much action.

 

Are you still running the stock cat...might be clogged.

 

Forgot how to read,......nevermind.

 

Am I the only one that noticed he has a 93?

 

Yep. It's been a long week, gimme a break.

 

not stock cats forgive me if im incorrect, but i dont have an MAF do I?

thanks for the help, i guess i thought it was just bad fuel curves or something that could be tuned. since its old it could just be a bad sensor somewhere. i have only 70k miles on it though, 67 when i bought it

 

Nope, that's the reason why I mentioned the fact you had a 93. They didnt' have a MAF sensor.

 

so i should take it to a speedshop or a dynotune and get it diagnosed for problem areas? i dont have any cool handheld computer deals, plus the 93 computer probably sucks hard. i cant even get an LT4 knock sensor

 

My guess is that your O2 sensors are shot. LT headers are known to kill them because it moves them farther from the motor so they won't get as hot. Also, yours is a 93 so it will not have the heated sensors. My car is doing the EXACT same thing yours is right now. Horrible gas mileage and SES light on for short periods of time. Goto a GM dealership and get them to scan the code for you. Hope this helps

 

hmmm, so I didn't notice that it was a 93.... What can I say, it was late

Just ignore everything I said and kick me in the ***