greaseman69

As far as I know there was no issue before I touched the plugs. They were 30k mile TR55s which is the exact plug I'm running new right now. Is does run poorly when the car is cold, if I give it about 50% throttle there will be a very noticeable stutter, goes away about a minute but then it will idle rough when at operating temp. You can feel/hear intermediate misfires especially when the car sits at idle for a while. If I give it WOT it'll hesitate (not stutter) for a couple seconds until it feels like actually accelerating typically past 2500 rpm. Good idea with feeling the heat of the cylinders after 30 seconds. After work I'm going to try that then pray the #8 wire is the issue since that's the only one I haven't touched since these new wires earlier this week.

I think I mentioned it but the tune is just a mail order by Frost I had done after I put longtubes and true duals on. I got it tuned because I raced my buddy and after a few pulls it was misfiring like crazy, way more than it is now.

RPM WS6

iTrader: (3)

I'm a bit confused by these two statements:

So just to be clear, there WAS a misfiring issue before this most recent plug change, but it sounds like that was cleared up some time ago? If so, how long (miles) ago? And you're saying that the only thing that was done to correct that previous misfire issue was to get it tuned?

Just trying to get all of this straight in case these two episodes of misfires are somehow related to the same root cause. Adding headers will require a tune to run optimally, but you shouldn't be getting crazy amounts of misfires on the stock tune just because you've added headers. So I'm thinking the root of this issue might predate the plug change...maybe something has gotten worse, etc. That's why I'm also interested in how many miles ago all of that happened.

greaseman69

Fair question...That was over 20k miles ago. After the headers it was running fine until I did a few WOT high RPM pulls, then the misfiring started. I did the plugs when I did the headers and haven't touched them until now. I thought maybe I blew an exhaust gasket but there isn't any soot even after all these miles and I've done a smoke test. I am curious what happened that night to cause the issue. I remember after I had the original misfire issue 20k miles ago I would be able to reset my ecm by pulling the battery for 30 min or so and it would drive fine. Once the ecm relearned it would act up again. It could be related but it was a very different level of misfire, but who knows?

wannafbody

iTrader: (2)

Did you bounce off the rev limiter? Could you have bent a pushrod?

greaseman69

No bent pushrod, I had an over-rev incident a few years ago and checked everything over and even replaced all my pushrods even though they were not visibly bent.
As for my current situation I may be jinxing myself but it actually feels pretty good now. Maybe feels a little off in 5th and 6th at low RPMs at WOT but that's not too important to me. I'm still feeling it out. I did put a good amount of silicone on the wires last couple times I messed with them, I doubt that would interfere with ignition but I wonder if some got in the way and is slowly being burned off. I'll keep my eye on it.

greaseman69

Alright I will apologize in advance for bumping this thread so much. But the issue is definitely back, it's weird that the symptoms vary slightly. So the idle is a little better, doesn't dip to 600 then shoot to 900 and drop anymore...but it does fluctuate from 800-850 (according to cheap scanner) and still have a certain intermittent "bump" to it. My most pressing concern now is the lack of power immediately after flooring it in any gear. It hesitates and takes about 1.5 seconds before I feel any real power. Noticed the black part of my temperature sensor has a slight wiggle to it and the gasket was pinched. I doubt it but could a temp sensor cause my issues? I broke it years ago and replaced it (probably with something cheap) and it's been fine since. Maybe I bumped it when doing the #1 plug this time? Also noticed a wire resting on a header, bent it out of the way, but that shouldn't cause drivability issues unless the wire was already compromised right? Maybe MAF...might go for a drive with it unplugged and see what it does.

RPM WS6

iTrader: (3)

Thinking back to those inconsistent O2 readings from one bank to the other...do you have access to an Ohm/Multi-meter? I would probably check resistance on all the injectors, look for one that might be out of spec as compared to the rest.

greaseman69

Yeah I do... I made a thread months ago about some greyish smoke when cold and most people thought it looked like a stuck injector though the seafoam I threw at it didn't do much. I'll give them a test, thanks

greaseman69

Good news!!! Haven't tested my injectors yet but did some reading and decided to test my MAF but unplugging it. Running the car with the MAF unplugged, it runs way better. The idle still isn't great but that may be chalked up to being on my original motor mounts (127k miles.) So I think the coincidence with the plug situation is this- After first feeling an issue with my new spark plugs, I cleaned my throttle body and MAF as well as changed to another set of plugs and wires. When I cleaned the MAF I didn't scrub them at all, just sprayed them with maf cleaner. Maybe the plug wires were a little loose but also spraying the MAF somehow exacerbated the issue? Either way, I'm going to use a Q tip on the MAF tomorrow and see what happens...The car feels faster than it has in a long time. Not gonna romp on it with no MAF though, worried a little about running super rich.

RPM WS6

iTrader: (3)

How are the O2 values looking now? I'd still test the injectors if the idle still isn't quite right, but there is certainly no harm in thoroughly cleaning the MAF with a Q-tip soaked in rubbing alcohol (which is something I often recommend to folks - especially if a K&N type filter has ever been used).

greaseman69

Well the O2 values seem pretty solid as of right now. But I think I finally found my issue. So I recleaned the MAF and it didn't seem to help...so I figured hey why not just get a new one and see if it does anything. Went to replace it and...there's a crack in my SLP lid right next to the MAF and IAT!!! Gonna get a new one but for now I taped it up pretty good and my car runs even better now. Feels great! Not sure how that even happened, maybe a quick change from hot to cold temps. Hopefully this is the end of my issue but thanks all for the advice. I haven't tested the injectors yet but once I can get my hands on a friend's multimeter I will cuz now I'm just curious.