ok, its a 96 ss camaro with 65k miles it sat for around a year when i first started doin the body work it ran perfect then it started missing very badly, so i put fuel filter,plugs,wires,opti,cap,and rotor...now it definately runs better but it misses on cylinders 4,6,8..the multiple misfire code is still there but now it has, the Iac intermittent spark code, and somethin to do with the air temperature being wrong, the scanner read the air intake temp at negative 40, im lost at what to do any suggestions or help is very appreciated i need this car on the road

 

I know somebody knows something about this ha, please help me out

 

What is "the Iac intermittent spark code".... never heard of that one? What is the number on the IAT sensor code? If it reads -40* (infinite resistance), it means either the harness connector is unplugged, the harness wire has an "open" or the sensor is burned out. Its easy to check the sensor with an ohm meter. Easy to check the wiring harness with a mutli-meter.

Generally, its better if you can just post the EXACT trouble codes, rather than some vague description of them.

 

Several unrelated codes are often (not always) due to a low system voltage. Either a bad battery, bad wiring or faulty alternator. Since you say it sat for a long time, you determine if one of those is due to sitting. It's very easy to eliminate low system voltage. Simply check the voltage across the battery while the engine is running to be sure it is around 14 volts DC.

Be sure the fuel you had in the tank the hole time it was stored is now removed since it will have gone bad by now. Here's a stretch but what if you had old lousy fuel that caused the engine to run so poorly, the alternator couldn't put out enough voltage and the system was in a sort of "brown" condition?

 

well, that does make some sense, but i messed with it over the weekend and i found out it had been run out of gas twice but it now has a full tank and some cleaner i changed the filter to, i hooked it to a scanner and it misses from idle to 2000 rpm after that it doesnt miss, also most of the time i start it it runs fine and then about a minute later the miss appears, i dont know what the deal is.

 

Clean the injectors on the car professionally. When this is done, it will also clean the rails as well.