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Catastrophic failure, or just bad gas?

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Old 10-07-2013 | 08:07 AM
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Default Catastrophic failure, or just bad gas?

So on the way to work this morning I was doing some pulls working on my PID settings on my EBC when during one pull I heard a bang or pop so I immediately let off the gas. I immediately shut off my stereo which was blaring, pushed in the clutch, and listened.

The car seemed to be running poorly, but I didn't hear any knock or rattles and I didn't see or smell any smoke or gas. Oil pressure remained steady. I gingerly drove down the road figuring that if anything was THAT catastrophic I would figure out pretty quickly.

I noticed that my AFRs seemed to be erratic, varying from 13-17:1 or so. Pulsewidths remained steady. I did a few mid throttle pulls to see what would happen. The AFRs remained steady at about 12.5:1 during the pull but immediately after I got pops out of my exhaust. I had this happen before but only when engine braking after being in throttle.

Also steady for the most part is idle. At idle I am staying between 12.8-13.3:1 which is pretty much where I have my idle at for cold mornings.

What worries me is that at low load cruise I was seeing AFRs bouncing between my target and about 17:1. I drove gingerly for about 15 miles like this.

I have some logs that I will upload in a couple hours. I DID just get gas before parking the car last night and no more than 7 miles after the fill up the problems started.
Old 10-07-2013 | 08:14 AM
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fix your intercooler coupler that fell off.
Old 10-07-2013 | 08:16 AM
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I will check that...

How would that cause my AFRs to be so high though?

Making a list of things to check...
  • Charge piping
  • Wiring to injectors
  • Grounds
  • ??

EDIT: Added log files.

According to the mild pull I was seeing 126kpa, which is a little bit of boost so I doubt it is my charge piping. Going outside in a bit to check.
Attached Files
File Type: msl
2013-10-07_driving.msl (186.3 KB, 89 views)
File Type: msl
2013-10-07_idle.msl (59.9 KB, 98 views)
File Type: msl
2013-10-07_mild_pull.msl (57.1 KB, 100 views)

Last edited by Chiburbian; 10-07-2013 at 11:08 AM. Reason: Adding log files
Old 10-07-2013 | 07:33 PM
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Ok, not catastrophic except a big case of the dumb. I had my MAP temperature adjustment too high and VEAL was pulling fuel from my map like mad to compensate. Once my car got warm I had already passed the max adjustment on those cells so it couldn't re-enrich.

All is fine now.
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