cyrax5709

Ok heres what its doing...under normal driving (no lead foot) its fine. But whenever I gas it off a light for example it "stutters". Smokes a little, smells like gas. My assumption is that for some reason or another its not detonating the fuel. Now some background info. Its an auto with 130 thousand miles, short ram intake, rrm v1 piggyback, straight pipe exhaust. Thought maybe it was bad gas, Got some injector cleaner then octane booster then back to injector cleaner. So far nothing has worked. I changed the coils, plugs and wires. No water in the oil, no oil in the water. Im a little stumped. Ive got two theories: number one is that I have a cracked injector; number two is that one of the exhaust valves is sticking open. when it does this it sounds like its running on 2 or 3 cylinders. cant really say for sure because it happens so fast. just has me a little worried. I want to figure out what the problem is before it gets any worse. any help would be greatly GREATLY appreciated.

ambystom01

iTrader: (7)

Take off the piggyback and see if that helps.

cyrax5709

That was going to be my next option...but I didnt really want to do that if I didnt have to...why do you think the piggy would have anything to do with it? Ive had it installed since...march...so yea...

ambystom01

iTrader: (7)

Figured it was a good place to start.

cyrax5709

I guess I should do that...maybe

eag36

iTrader: (2)

I'm assuming no check engine lights?

Go2fast

Has the weather changed lately were you live? If its been hot and then gets cold the piggyback acts up until it adapts. But i dont really think that would be the problem.

My first guess is "Check the MAF sensor!" Usually when that goes bad or is hooked up wrong, the car stutters, runs like ****, shuts off, and runs super rich. The cars ECU dumps a bunch of fuel into the motor to protect it from leaning out.

Also, check and read your plugs. They will tell you alot.

mauisurf2003

u check ur plugs/
color?

comatose721

iTrader: (16)

2 questions: 1.) is your CEL on, and if so what is the code? 2.) which cylinder(s) are not firing?

-make sure you are actually getting spark to each cylinder. i had the exact same problem, it came down to a lead running to the 2nd coil pack was scorched by the cylinder head(till this day i have no clue how the wires came to rest upon the head). the short cause 2 cylinders to not fire.

-also, if you have the tools available to you, run a compression test. although it doesn't really sound like a compression problem it's a simple test that i would run.

-check your exhaust for unburnt fuel. if 1-2 cylinders aren't firing and you still have that putrid stench of gas (or actual unburnt gas on the runner of your exhaust mani) you can pretty much rule out the idea of a faulty injector.

cyrax5709

Ok update. Yes the weather changed recently got extra cold extra quick. checked/replaced the plugs. Tried some throttle body cleaner that worked for a couple days now its back worse than before. I didnt realize they make MAF sensor cleaner. so thats my next target. It is dumping alot of fuel... alot. It seems like the colder it gets the worse it gets. Could it be a vacuum problem? Does anyone have a diagram of the vacuum lines for the TB?

cyrax5709

O right CEL ok it is on...but its always on I dont have any cats. However it is throwing a few new codes LoL. One is "System mixture Too Rich" the other was "Misfire cylinder 4". Now, which one is cylinder 4? It said that code before we changed the plugs and hasnt done it since. but now it just constantly says its too rich. Ok I also checked both the coils...they are good...checked them against a new one. tested resistance and all that good stuff...

sykou

iTrader: (19)

Could it be caused by the seals on the valves? forget what they're called...valve end seals? If they are leaking, oil could be leaking into your cylinders, which burns causing it to smoke and lose compresion. that may cause the studder you are talking about...

iyi0521

iTrader: (6)

Pull the piggy and reset the ECU. Drive for 2 days to make sure the ECU has relearned and then get back to us.

clearskies

I just recently cleaned my engine and had a "Misfire cylinder 1". They count left to right, 1 2 3 4, ( with you standing in front of the car facing the engine that is.)

I looked at it and it was not fully plugged into the block, it was separated, i assume from my deep clean of the engine. Pulled it out, put it back in, reset the cars computer, and good to go.

Although now im getting 23 MPG and I believe another one is misfiring but the computer isnt on showing a problem... HMm...

Hope that helps!

cyrax5709

yea just gotta wait for some good weather to pull the piggy out...too damn cold lately LoL but Ill let you guys know for sure