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Power Loss at high boost

 
Old 07-31-2001, 12:39 PM
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Gnftr56
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Wink Power Loss at high boost

I have been experiencing a problem with my stock 87 951. Whenever I am running the car at high boost (1.5-1.6 on stock gauge), the car stumbles pretty badly. The boost remains high, but it feels as if you slam on the brakes all of a sudden. As soon as you let out a little on the gas it is ok again. I tried going with better spark plugs (NGK and Rebu) and a new set of wires, to no avail. I even swapped in a KLR box to see if that was the problem. Could it be a fuel flow/pressure problem? Anyone have any ideas??
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Old 07-31-2001, 01:06 PM
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Eric
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I had a similar problem/occurence on a stock 86. Could be a vacum leak, OR over-boost protection kicking in to prevent an unpleasant detonation. Mine turned out to be a vacum leak. Good luck.

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Old 07-31-2001, 01:32 PM
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fletch.
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That sounds like a leak in one of the boots to the turbo or intercooler, when you boost up your leaking someplace. Check all intake and turbo boots. Check the pop off as well they can crack and leak.
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Old 08-04-2001, 08:50 AM
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Danno
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The outlet hose on my '86 was getting old and slippery. I kept on tightening up the hose clamps, but it still slipped. Finally, I tightened it up so much that it cut through the hose.

So I went to Kragen's and found a 2" radiator hose that had the right bend angle and cut it to the correct length. Also used TWO hose-clamps side by side on the turbo outlet and intercooler pipes. Also on the intake-manifold adapter hose.

Been holding up like a charm. Oh, also clean all mating surfaces with acetone to remove all traces of oil.

-danno
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Old 08-06-2001, 03:23 PM
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Olli Snellman
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Check carefully out what Fletch supposed.I am olmost sure there's an answer to your problem.

Olli
'88 951
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Old 10-30-2001, 01:19 PM
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Gnftr56
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Talking

Thanks to everyone for the help. Finally had time to leak check it and found the vacumm leak. Changed the line and it works great.
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Old 10-31-2001, 02:55 AM
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Danno
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So where was it leaking?
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