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View Full Version : Need help to diagnose starting issues



suju82
06-05-2010, 11:34 AM
Drove the car around yesterday afternoon and it was good and then parked for a few hours and it wouldn't start. Cranked it over and over and nothing. Started the car up this morning and it started right away. No codes when i scanned it. Logged the car for about an hour or so while driving around. I was getting a missfire on cylinder 1 every 5-10 minutes, and on cylinder 3 every 15-20 minutes and got a missfire on cylinder 4 once in the entire time i was driving. Sparkplugs are all new from about two weeks ago bkr7e properly gapped. Coilpack # 3 is brand new from a month ago which is why it's wierd that it's getting missfires. They are all soft missfires so i'm not getting a CEL or codes showing up. The only i can think of is my MAF is on it's way out. car is k04+giac chip, tt dv, catback exhaust and k&n drop in filter. Any other suggestions?

walky_talky20
06-05-2010, 01:14 PM
If you get a no-start situation again, you can try unplugging the MAF. Other than, I'd check out coolant temp on cold and hot starts to see if there's anything funny there. Incorrectly reported coolant temp can cause air/fuel ratio problems when starting.

10kredline
06-05-2010, 02:56 PM
This is the same thing that's happening to my mom's A6 2.8. It sometimes starts and after parking it, it won't start. I asked a local german auto shop and the guy said it might be electronic failure...maybe ignition module going bad?

suju82
06-16-2010, 02:09 PM
Update: The car started the next morning but there were no codes. A day later when i started the car it sounded like a subaru and got missfire codes on cyl 1 so put in a new coilpack. I still here the farting/backfiring/missing noise once every other day so i'll try logging the car to see if i'm getting any missfires on cyl 2 and cyl 4 as coilpack in cyl1+3 are new and all plugs are new bkr7e. I did log it the other day and in a 25 min drive i got 1 soft missfire on cyl 1 which was wierd. I have a new ICM in the glovebox just incase the current one craps out while i'm out somewhere. Haven't had any starting issues so far since changing the coilpack.