Thread: 930 misfire
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mark houghton mark houghton is offline
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Join Date: Jul 2008
Location: Central Washington State
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Originally Posted by 930cabman View Post
The misfire does seem ignition related, that is why I started with the plugs. I purchased the 930 in 2009 and have been running it with basically no issues, so it seemed logical to at least new plugs were in order.

The misfire is under load (boost condition) and it feels as a bad plug would. For this reason it would seem the wires, cap and rotor are next. I suppose $200.00 is not too much for a roll of the dice. I could find a shop and let them guess I suppose.

thanks again,
John G
Miguel and Mike both tossed out the possibility of something other than ignition related issues. Since you're seeing this under load (and particularly under boost), it could be as simple as a blown o'ring on the intercooler. That will cause you to run pig-rich when under'll have a dramatic lack of power and a hard time taching out the engine. Stutter stutt stutt, run like crap when any boost is built. When's the last time you had your IC off and checked the o'rings and such? Maybe put that possibility to bed before replacing ignition stuff.

One more question: How's your idle? Smooth, or otherwise? An intake leak in CIS turbo cars would cause lean conditions at idle, and rich under boost.
Mark H. 1987 930, GP White, Wevo shifter, Borla exhaust, stock everything else. The result of a massive Pelicanite good will fire recovery effort. Truely an open book, ready for the slippery slopes to modification.
Old 05-16-2012, 06:13 PM
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