car trouble, need help

[b3master]

hi all, i have the 95 V6 camaro

symptons are: somtimes not always, under heavy load/acceleration or pressure on the engine, or just randomly, the car will start to studddder like a bad spark plug.... a week ago it would act like 2 spark plugs were not working or oiled up but now it does it as if just one is oiled up...

now here is the deal, while the car is still on and moving if i turn it off and on again the studder goes away, so it is NOT any spakplug its not any sprkplug wire, and it is not and injector otherwise it would ALWAYS do that.... its has to be electric because symptons go away when i turn off and on again...

i thought it could be the feul tank not enough pressure, but i replaced it im down $160 and now this studder is back and my feul mileage is very very very incredibly lousy under 10mpg now the ses light used to come on so it was checked on the hand held mechanic diagnostics computer it showed just an oxygen sensor...

now i dont think an oxygen sensor would be doing all this trouble.. there isnt a distributor block so what ever u call the things that give electricity to the spark plugs are my best guess, any help totaly appreciated thanx

[b3master]

here is somthing weird that happened yesterday, i was driving arround on a carppy road and the wheels passenger side went through a hole about 1.5 inches deep maybe 2, after that the cars started studdering, can it possibly be mechanical misfunction
no one has any ideas? my feul mileage is very crappy, like 11mpg city

i just cant understand why it does it SOMTIMES and when it does act crazy and studders on 5 cylinders i just turn off and on and its gone, its gotta be electrical, and now why would runing over a hole do it...

what can make a car studder/run on 5 cylinders???

[Joe 1320]

My bet is a loose electrical connector or a loose ground. I would start the engine and start playing around with all the connections until you find the problem.

[b3master]

well the O2s were definatly bad changed those, and the tps wasnt working properly also messing up my gas mileage, so i do have improvment on gas mileage now hway is at 25.5mpg even though somtimes i was driving at 100mph

but the main problem of studder still occurs, rarely but surely if i wanna realy slam on it, shifting at 5k+ rpm or i wanna do a 90 or 180 slide that is when the studder comes, its when the motor is under load, and as soon as i turn car off and on it goes away... so sadly folks what im thinking is the only problem is actualy the computer going bad on me since its just a matter of RESETTING it turn off and on and it works fine, then its gotta be the pcm might need reprograming or a new one

anyone know where i can get one from a salvage for cheap?

[Joe 1320]

You need a scanner to see what is happening. You can keep changing stuff, but unless you read the sensors at the time of the studder, you really don't know what is happening.... you're guessing.

[N20LT4Bird]

Yes, do yourself a favor and dont throw parts at it. If you dont have the equipment to diagnose the computer controlled system, take it to a reputable shop. The problem could be one of about 100 things.....You will waste a lot of money on guessing.

[b3master]

if it is the computer how much is it? and how much can it be found from a salvage yard? 95 V6 3.4 manual tranny computer

[Bond Hawk]

Try popping the hood with the engine running at night. If you see any electrical arcing, there's your problem. Make sure it's really dark out when you do this. May need to replace the plug wires if you see any arcing.

[b3master]

thanx every1 for the help and responce, sure thing hawk when it started studdering last night before i turn of and on i gave that a shot and sure as hell it was arcing what happened was i realized spark plug #6 was black not combusting properly, i dont know why but instead of trying to replace only ITS plug i replaced both it and #1 as it was i replaced #6 with a good plug BUT #1 with a bad one that cause the studder to get weaker but was still there, but also other plugs were also weak and when shaken they would arc a bit and they were extremly hot when operating which means high resistance.... now finaly i changed them all and the studder hasnt come back yet thanx all...

i have a new question though

so spark plug wires replaced and bad TPS and bad o2 sensors all replaced along with the feul pump, but now i AM getting that gas smell, does that thing called (evaporative carninster ) affect gas mileage? if it does ill replace it, if not is there any effects for keeping it malfunctioning?

i get gas smell when i turn the car on or off, but not during driving... or maybe i just dont realize it that much... why does it give out smell what does it do??

[Bond Hawk]

Glad you were able to fix the problem you were having. I've heard that overfilling the gas tank can soak the charcoal cannister, so it may just need to dry out.

The EVAP system has a lot of parts that work together. In addition to the canister itself there are all types of other components. Take a look at the following picture:

http://shbox.com/1/evap_system.jpg