Cyl 4 misfire, Boost control below threshold, limp mode while logging... Just replaced coil pack...

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Jun 23, 2008 | 08:50 PM

Stonediggity

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Cyl 4 misfire, Boost control below threshold, limp mode while logging... Just replaced coil pack...

Hey all - been a while since I've been over in this forum, spending all my time in the Rocky Mtn Regional board.

I've had a CEL for a week or so for a Cyl 4 misfire. I figured the easy answer was coil pack, the harder answer was injector... I dropped in a coil pack tonight, fired her up and she ran smoothly, but after a few pulls I started getting intermittent misfires again... Injector?

I was also going to run some logs for Tony @ EPL to see about some overboost I've been noticing and while running a log of 114 and 115 in 3rd from 2k - redline I go into limp mode on the first pull with a code of boost control below threshold (not sure the wording, and I don't have my VAG computer here).

So I figure that means N75 kaput?

Is there any alternate explanation for the Misfire besides injector if the coil pack didn't do it?

Thanks!

- Aaron

Jun 23, 2008 | 09:39 PM

2fst4u2c

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wouldn't the "easy" be the plug? if not plug or coil, check ignition amp before injector...

Jun 24, 2008 | 06:57 AM

Stonediggity

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I'll swap the amps tonight - thanks, I apparently did a **** poor job of STFA

Jun 24, 2008 | 07:47 AM

2fst4u2c

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good luck, post your findings...

Jun 25, 2008 | 05:26 PM

Stonediggity

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Replaced all 6 plugs and switched the amps. Didn't fix it... I guess it's time for an injector.

I replaced all plugs with NGK bkr7e gapped to .030 and swapped the amps and cylinder 4 is still mis-firing at 1-2 misfires a second. N75 is on order, maybe I'll throw an injector in and hopefully that and the N75 will fix my issue.

Any other potential causes you can think of?