Got a misfire issue and the car doesnt want to stay running. I highly doubt this is tune related. I need some ideas as to far whats causing this. I need to figure it out and im not spending thousands of dollars on labor to have someone do it. The car runs like *** hot/cold for about 15 minutes then it clears up/runs strong/perfect. Once it clears up you could drive it 100+ miles and have no issues till you let it die or shut it off. Someone mentioned to me there could be a vac leak inside the intake.

I have a fast intake. I took the intake apart and replaced the gaskets internally inside the intake as well as the individual 8 gaskets. I cleaned the map sensor up and bought that other grommet that makes it a tighter seal. I also wrapped it in teflon tape to get a even better seal, I've checked for vac leaks, changed the plugs/wires, replaced the coolant temp sensor as i've read it can keep the car in open loop if its messed up. Replaced the IAT sensor, cleaned the maf real well, ditched the K&N for a paper filter fearing oil could have gotten on the maf, checked the o2's they look fine but I guess that doesnt really mean **** now does it. In the video when im stopped im standing on the throttle. It will NOT idle on its own. While driving it misses and does all kinds of embarassing stuff driving down the road. If you even think of turning the a/c on the car will hardly run at all. It will die while just going down the road. I opend the cutout once so you can hear it real good. Any other suggestions besides replacing the o2 sensors? I do have 2 codes. they are p0102 and p0103 codes. Mass or volume air flow circuit low input & mass or volume air flow circuit high input. If you unplug the maf it does the same thing. Its also tuned with the maf. This is more of just an inconvenience but I guess I can live with it for the 15 minutes. Any ideas would be appreciated that I could check. Thanks

http://www.youtube.com/watch?v=6YCU9nF9qGs

 

Wow, that sputtering is bad. I wouldn't drive it until you find the problem.

* What MAF are you running?
* Make sure the MAF is installed correctly with the arrow pointing in the right direction.
* Do you have a scan tool to log data? That would really help.
* Double check for vacuum leaks and make sure the intake is completely seated on the cylinder heads. Did you bend the front coolant line down so the bottom/front of the intake doesn't touch it?
* Did the car ingest some water recently?

However the fact you're getting both low and high voltage codes indicate something is really wrong with the MAF or you have a major intake restriction because the MAF is operating completely outside of the entire frequency range (too low and too high).

I would disassemble and thoroughly inspect the entire intake assembly from the airbox to the rubber connector that connects to the TB.

 

I once had a similar issue with our 01 ta after a local dealership put a new trans in it. turns out they pinched the drivers side injector circuit wire behind the pass side head. it blew the fuse under the hood and would run like ***. replace the fuse it would run like *** for a little and then blow the fuse.
not saying it is the injector circuit but you might check the harness for bad wires. good luck!

 

Generally, a misfire like that is an ignition problem. You say you changed the plugs and wires, but did you check the coil packs? One of those may be on its way out.

 

The maf is stock. It's installed right. Another thing the car is tuned for the maf. If you unplug it it still runs the same if that matters. Someone mentioned the intake to me as there could be a leak inside. I just took my fast intake completely apart friday and replaced all the internal gaskets as well as the 8 individual intake runner gaskets. I dont have a scan tool. I've checked for vacuum leaks. It hasnt seen any water. Im going to buy a wideband today and see what it's doing.

 

Just checked the fuses they are ok.

I guess I could unplug each one by one and see what it does but it would miss for each cylinder so im not sure I would be able to feel it. I may swap coil packs with someone today and see if that gets me anywhere. I want to think its somthing in the ignition as it only goes on for 10-15 mins after startup

 

check the plugs, see which ones are dark and white

 

Any other suggestions?

 

unplug the 02 sensors, that will make the car run in open loop(warmup period). Just to rule the 02 sensors out.


and maybe you should swap someone else's maf in to test?

 

disconnect the battery and hook it back up? might sound stupid but i installed new o2 and a whole new exhaust and my car would not act right... similar to what urs is doing so i disconnected the battery and reconnected it and it is fine now

 

When I get back in town from work I am going to try this. ALso should have my new wideband hooked up in a couple days maybe I can get an idea whats going on

 

Unplugged the o2's today ran like *** obviously but didnt sense the stumbling and misfiring. Gonna put some new o2's in tomorrow well see what happens

 

Did this fix your problem? I'm having a similar problem.

 

one time i popped on a curb and the plug and the wired messed up. don't ask me how. check the spark plug wires. I had the same problem man.

nm, i just read you did that. man ill try to think back to what else it was.