Random misfire occurs @ 6000 rpms, need help.
I think you answered your own question. You fixed the problem then kept fixing it till you broke it again. Half of tuning is knowing when to quit.
"we checked the plugs and tried re-gapping them down from .27 to .23 and the problem cleared right up"
"we checked the plugs and tried re-gapping them down from .27 to .23 and the problem cleared right up"
Last edited by cfdfireman1; Oct 8, 2007 at 07:55 AM.
I just re-installed my NGK BRP8ES gapped .21 and the misfire almost seemed worse, I had a pretty decent backfire. We're going to check the factory ground by adding an additional ground to see if it's related to a faulty ground off the battery. I sure would love to figure out the source of this misfire. When I take it to the shop and we road test it, they should be able to data log it to see what's going on when the misfire occurs. I'll let you know what I find.
I just installed BPR7ES plugs gapped @ .21 and snap,crackle, pop, same thing. We're going to check the cam timing sensor & the grounds just to be safe, if that checks then in goes an ARC2 or M&W Pro 12. Here's a link to what I'm looking @
: http://cgi.ebay.com/ebaymotors/ws/eB...m=320168458141
: http://cgi.ebay.com/ebaymotors/ws/eB...m=320168458141
I have replaced the coils and the wires.....still didn't fix the problem. I am begining to think that there is a faulty sensor some place.
Upon doing some data logs I discovered that my throttle position sensor is reading 13% open at idle and 69% at WOT. This might be part of the cause.
Also my Throttle Body seals leak like crazy. New ones are on the way.
Finally, I also got a new set of stock iridium plugs.
I will install and repair and test again and fill you all in on the results.
Upon doing some data logs I discovered that my throttle position sensor is reading 13% open at idle and 69% at WOT. This might be part of the cause.
Also my Throttle Body seals leak like crazy. New ones are on the way.
Finally, I also got a new set of stock iridium plugs.
I will install and repair and test again and fill you all in on the results.
If you were referring to me, as noted in the original post, we already swapped out the plugs & coils (although we took them off of two different cars that had no known issues).
Appaulld,
The shop I use told me of a guy who had similar issues w/ a misfire and he had swapped in a COP system on his own, only to find that the misfire was still occurring. he took it to Marco @ Billet Design suggested that they check his cam position sensor, which turned out to be the problem. So I'll be checking my sensor in the next day or two to make sure that's not the problem. I wanted to pick up an ARC2 from TTP but they're out of stock.
Appaulld,
The shop I use told me of a guy who had similar issues w/ a misfire and he had swapped in a COP system on his own, only to find that the misfire was still occurring. he took it to Marco @ Billet Design suggested that they check his cam position sensor, which turned out to be the problem. So I'll be checking my sensor in the next day or two to make sure that's not the problem. I wanted to pick up an ARC2 from TTP but they're out of stock.
I guess I missed what you were saying. You think the Sun system may be part of the problem?! I'll give it a try, but it did it prior to the sun being installed.
If i were you i would use a set of fresh bpr7's, gapped at stock 0.26 or 0.25
I know you've said you tried, but you say you took em off another car... It happens to me pretty much every 4-5 weeks because plugs get worn out, so i replace them often.
Also try taking that Sun out. I don't see why you'd need one at 23psi on a green, unless you play with race gas every one in a while. Still take it out to rule it out.
I know you've said you tried, but you say you took em off another car... It happens to me pretty much every 4-5 weeks because plugs get worn out, so i replace them often.
Also try taking that Sun out. I don't see why you'd need one at 23psi on a green, unless you play with race gas every one in a while. Still take it out to rule it out.
I'm going to remove the Sun system as advised, but the plugs where brand new ones, so i will re-gap them to .26 and road test again. What I swapped out of my car wasn't a set of plugs, but two sets of plug wires & coils.
I'll let you know how it goes.
I'll let you know how it goes.
Well, here's what I did. I disconnected the Sun system and re-gapped my plugs to .25-26 and took it for a drive, the misfire was still there, but not nearly as pronounced, so I pulled my plugs & re-gapped them down to .20-21 and tried another road test. It was still missing about the same at 1st but then as I drove some more it began to clear out until it was almost gone, just occasionally & ever so slightly. I could make 5-6 passes up to 6800-7500 rpms and it would only sputter a tad 1 out of 6. Now I'm wondering if this confirms that it's my ignition or a ground. I'm leaning towards the ignition.