Severe probs after throttle body conversion!

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braincat
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Tue Mar 14, 2006 6:50 pm

After fitting a 2.5 body to my 2.0 the idle speed was pretty high (1500) though the car ran fine otherwise. I've identified the high idle problem as air getting past the throttle valve, which I've managed to bodge fix at work today, but on driving home there was severe knocking, almost sounding like I'd got road-kill wrapped around a moving part. Could this be a vac leak from the temporary fix, or have I properly knackered the car?
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chu346
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Tue Mar 14, 2006 7:01 pm

See if you can find where the knocking is coming from. You can put a long screwdriver on parts of the engine then next to your ear to see if it's that part which is making the noise.

And what was your fix? has it come loose?
fuzzy
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Tue Mar 14, 2006 7:08 pm

eh? a long screwdriver on parts of the engine to find out which bits knocking? i dont understand that,it would need to be about a metre long with a 90 degree angle on the end to hold against your ear ,unless you stick your head out the side window ,and youd better hope you dont hit any pot holes! expain? :?
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braincat
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Tue Mar 14, 2006 7:11 pm

The fix was pretty rough I must admit. My throttle body didn't have the inlet fitting on the top right (apparently some don't) so my local twat mechanic put one in to connect to the bellows. This seemed pretty silly to me as that puts air straight past the butterfly plate so I unhooked them and put some plugs into the hose and bellows which I secured with hose clips. Brought the idle speed back to normal but now knocking.
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chu346
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Tue Mar 14, 2006 7:29 pm

fuzzy wrote:eh? a long screwdriver on parts of the engine to find out which bits knocking? i dont understand that,it would need to be about a metre long with a 90 degree angle on the end to hold against your ear ,unless you stick your head out the side window ,and youd better hope you dont hit any pot holes! expain? :?
You thought I meant when the car is moving?
gcorky
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Tue Mar 14, 2006 7:35 pm

chu346 wrote:
fuzzy wrote:eh? a long screwdriver on parts of the engine to find out which bits knocking? i dont understand that,it would need to be about a metre long with a 90 degree angle on the end to hold against your ear ,unless you stick your head out the side window ,and youd better hope you dont hit any pot holes! expain? :?
You thought I meant when the car is moving?

oh my god ,weve had some good uns this week!!!lmfao :mad:
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braincat
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Tue Mar 14, 2006 7:46 pm

Just to clarify, the knocking sound only occurs during acceleration, but disappears at higher revs. Typical of vac leak?!
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chu346
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Tue Mar 14, 2006 8:01 pm

Does it make the noise when stationary and reving the engine?
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braincat
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Tue Mar 14, 2006 8:08 pm

Nope, idle is fine and revs fine, only seems to be in motion and defininately wasn't there before the bodge job. I'm really not too sure about the hoses on the right hand side (from bellows side) of the throttle body. They were both in use with the standard 320 body, and seem to be in some 325's I 've seen. Yet the zone guide shows a picture of the bellows without a connection to the top right hose... I'm messing up somewhere here I can feel it!
fuzzy
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Tue Mar 14, 2006 8:19 pm

ahh,its all becoming clear now,i did think you meant when driving chu346 as he said the knocking was happening during driving.its making more sense now though :D
Widge
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Tue Mar 14, 2006 8:28 pm

Try reversing your fix and see if it still knocks? Then you will know if it is related to the whole TB thing or if it is just coincidental. I have often had problems that pop up when doing somthing else and have nothing to do with it and then compound the diagnosis.
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braincat
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Tue Mar 14, 2006 8:32 pm

Cheers mate, will try the reversal in the morning and hope the knocking goes. I'll be at sqaure one with the high idle though if anyone has any theories. Checked the TPS and thats functioning fine, may just have to revert to the original throttle body and forgoe the power increase. Still there's always my 635 for that!
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braincat
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Wed Mar 15, 2006 6:32 pm

Ah, problem solved. Drove it with the windows up this morning so could hear the noise better, turns out it was coming more from the rear. Had a look and saw rather a lot of oil smothering my diff, particularly the left side. Looks like blown seals then.
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Steviec
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Wed Mar 15, 2006 7:39 pm

braincat wrote:Looks like blown seals then.
I got kicked out of the zoo for that :duck:
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Wed Mar 29, 2006 7:48 am

Steviec wrote:
braincat wrote:Looks like blown seals then.
I got kicked out of the zoo for that :duck:
:chuckle:
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