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Idles fine but no power...and backfires.

Old 04-11-2009, 11:51 PM
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p2ii
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Unhappy Idles fine but no power...and backfires.

Here's the story. I was accelerating in 3rd gear to about 5K rpm and I then felt a noticeable hesitation. I let off the gas and there was no engine braking sensation at all. I gave it throttle and there was no more power. It began to backfire and would not accelerate. I had to limp back to the house(luckily only a mile or so) The car seems to run fine at idle, just nothing under load. I'm thinking maybe it skipped a couple teeth on the timing belt and possibly bent a valve...any ideas. Thanks.


-Pat
Old 04-11-2009, 11:54 PM
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JohnKoaWood
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Originally Posted by p2ii
Here's the story. I was accelerating in 3rd gear to about 5K rpm and I then felt a noticeable hesitation. I let off the gas and there was no engine braking sensation at all. I gave it throttle and there was no more power. It began to backfire and would not accelerate. I had to limp back to the house(luckily only a mile or so) The car seems to run fine at idle, just nothing under load. I'm thinking maybe it skipped a couple teeth on the timing belt and possibly bent a valve...any ideas. Thanks.


-Pat
+1 check your timing... and the distributor button under the cap, might it have slipped?
Old 04-12-2009, 12:35 AM
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Check your rubber couplers from the turbo out all the way to the throttle body, sounds like you have blown one off or there's a hole in one of them.
Old 04-12-2009, 01:31 AM
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bigdeano
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Check the couplers on the IC pipes.
Old 04-12-2009, 04:29 AM
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And check the hoses connecting to the IC pipe.

If it skipped more than a tooth or two, it wouldnt be running.
Old 04-12-2009, 08:37 AM
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Thanks for responses! I'll check those things out and report back. It was the part about the no engine braking while in gear that led me to think maybe a valve issue. I'll definitely be much happier if it's just a hose or coupler though

-Pat
Old 04-12-2009, 08:57 AM
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also check your afm if you still have one- make sure the door is moving properly and not stuck.
Old 04-12-2009, 02:39 PM
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How far is Easly from Hendersonville? If you need help, I may be able to help in the next few weeks if you haven't fixed this.
Old 04-12-2009, 03:29 PM
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Originally Posted by black944 turbo
How far is Easly from Hendersonville? If you need help, I may be able to help in the next few weeks if you haven't fixed this.
It's an hour straight down 25 basically. Hopefully it is something simple. I'll post up either later today or tomorrow with an status. Thanks.
Old 04-15-2009, 09:43 PM
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Originally Posted by xsboost90
also check your afm if you still have one- make sure the door is moving properly and not stuck.
If this is the unit connected directly to the airbox then I believe it may be the culprit. I only had a few minutes looking at it but could hear the rushing sound of air through it at idle. That is definitely not the normal sound under the hood when idling. When I manipulate the throttle by hand the car stumbles as if it is about to stall. Also, while it was idling I removed the connector plugged in to the unit and the car died, which I expected, so it appears that bit is functioning.
Old 04-15-2009, 10:09 PM
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jlturpin
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You might also check the hose that comes off the turbo to the intercooler. I had one that split on the underside, just past the hose clamp. Sounds like you have a hose blown past the turbo.
Old 04-17-2009, 01:52 PM
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The other suggestions are right on but also; see the small screw at the very center of this pic (top of the throttle body), is yours missing/hissing from there - those little puppies get blown out sometimes... Bruce

Old 04-27-2009, 10:02 PM
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Okay so I finally had some time to look at it. The rubber couplers on the intercooler look fine as do the others. When I pull the connector from the tps the idle comes up and it seems to rev better without stumbling so I'm leaning that way. What is the best way to test the tps and afm? I'm guessing I would need a volt meter to check the signals. BTW the set screw on the tb is still intact and has not moved from it's normal spot. Thanks!

-Pat
Old 04-28-2009, 09:10 AM
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mine was do'ing the same thing when my tps went.New tps fixed it ,then a few months later was getting similar simptoms, but not as bad. found torn bypass valve diaphram. repaced that and now all is well.
Old 04-28-2009, 10:16 AM
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I'm going to test the tps and afm. Will clarks-garage have those readings/procedures?

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