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bmorecam · 03-10-2012, 08:04 PM

I am freaking disappointed/angry/worried as I don't know WTH is going on right now

. I'm not sure if this is related to the new cam phase adjustment testing me and vince been doing for these last few months, but like a month after I been driving with the new tune, every now and then my car would choke, bog, and basically act like couple cylinders are not firing only during cold start, but as soon as the rpm come down, it would be as smooth as butter like the hard start did not even occur and no CEL.
Anyway, just a few days ago it happened again, but this time I got a CEL for multiple misfire on cylinder 2 and 5. I cleared the code and reverted back to the old tune, the next morning it happened again, another CEL for misfire during cold start, I cleared the code and decided to run some techron fuel system cleaner, the next cold start was ok, the cold start still seemed a little rough than usual but no CEL and not as boggy and no choking. cold start again just about an hour ago but this time I monitored the misfires in real time, cold start was ok as before, a little rough than usual again but no CEL, but the crazy thing is that I am seeing 34 misfires in cylinder 1 and couple on all cylinders. No CEL yet but there was a pending misfire CEL on cylinder number 3 this time.

I need some help from you guys this time. It seem this is only happening during cold start only. After the initial cold start everything is smooth as butter with not even 1 misfire on any of the cylinders. If I had to guess it look like a problem that is persisting, but I don't know what it could be

I need your expertise on this guys.

03-10-2012, 08:04 PM	#1
bmorecam Account Suspended Drives: jealous vendors mad!! HAHA!! Join Date: Jan 2011 Location: CYBERGMONSTER@GMAIL.COM Posts: 3,658 View My Garage	Cold start misfires. I think this is more serious than I thought! I am freaking disappointed/angry/worried as I don't know WTH is going on right now. I'm not sure if this is related to the new cam phase adjustment testing me and vince been doing for these last few months, but like a month after I been driving with the new tune, every now and then my car would choke, bog, and basically act like couple cylinders are not firing only during cold start, but as soon as the rpm come down, it would be as smooth as butter like the hard start did not even occur and no CEL. Anyway, just a few days ago it happened again, but this time I got a CEL for multiple misfire on cylinder 2 and 5. I cleared the code and reverted back to the old tune, the next morning it happened again, another CEL for misfire during cold start, I cleared the code and decided to run some techron fuel system cleaner, the next cold start was ok, the cold start still seemed a little rough than usual but no CEL and not as boggy and no choking. cold start again just about an hour ago but this time I monitored the misfires in real time, cold start was ok as before, a little rough than usual again but no CEL, but the crazy thing is that I am seeing 34 misfires in cylinder 1 and couple on all cylinders. No CEL yet but there was a pending misfire CEL on cylinder number 3 this time. I need some help from you guys this time. It seem this is only happening during cold start only. After the initial cold start everything is smooth as butter with not even 1 misfire on any of the cylinders. If I had to guess it look like a problem that is persisting, but I don't know what it could be I need your expertise on this guys.