No Boost Question..
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According to Clark's Garage's 951 FAQ it says:
How can I tell if my clutch is slipping?
Does it make some sort of noise?
(The turbo could actually be working but a slipping clutch could absorb all the turbo boost and make it seem as if there is no turbo effect.)
Does it make some sort of noise?
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Put it in 4th gear @2500 and stomp on it. Once the boost builds and the torque grows, the engine will gain revs but the car won't gain speed. Sometimes it it very subtle, but you WILL notice. Basically you are losing the forward drive. Clutch slippage usually occurs at the torque peak and you won't notice it (if it's not too bad) unless you are at full throttle.
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A slipping clutch will allow the RPMs to rev upwards with no change in speed. Although a slipping clutch actually doesn't 'absorb' boost so much as it doesn't allow the engine to build up enough load to even generate boost in the 1st place. Kinda like free-revving the engine in neutral. Didn't someone report once that they had to floor their engine while it was on jackstands to generate a little boost?
Anyway, no boost could be a sign that you have a clogged cat, exhaust leaks in the crossover pipe (typically at wastegate joint), or a failed wastegate. I've seen really old turbos with worn bearings or bent axles do this as well.
Anyway, no boost could be a sign that you have a clogged cat, exhaust leaks in the crossover pipe (typically at wastegate joint), or a failed wastegate. I've seen really old turbos with worn bearings or bent axles do this as well.
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Originally posted by Danno
A slipping clutch will allow the RPMs to rev upwards with no change in speed. Although a slipping clutch actually doesn't 'absorb' boost so much as it doesn't allow the engine to build up enough load to even generate boost in the 1st place. Kinda like free-revving the engine in neutral. Didn't someone report once that they had to floor their engine while it was on jackstands to generate a little boost?
Anyway, no boost could be a sign that you have a clogged cat, exhaust leaks in the crossover pipe (typically at wastegate joint), or a failed wastegate. I've seen really old turbos with worn bearings or bent axles do this as well.
A slipping clutch will allow the RPMs to rev upwards with no change in speed. Although a slipping clutch actually doesn't 'absorb' boost so much as it doesn't allow the engine to build up enough load to even generate boost in the 1st place. Kinda like free-revving the engine in neutral. Didn't someone report once that they had to floor their engine while it was on jackstands to generate a little boost?
Anyway, no boost could be a sign that you have a clogged cat, exhaust leaks in the crossover pipe (typically at wastegate joint), or a failed wastegate. I've seen really old turbos with worn bearings or bent axles do this as well.
Regarding the cat, the PO (who was a Porsche mechanic) replaced my cat when I bought my car because it failed smog, around 3k miles ago.
Although, I have been hearing a weird ringing noise/chiming coming from under the car, sounds like a nut or bolt is moving around in the cat.
I'm thinking of removing the cat today, what should the inside look like?
Thanks for the help Danno.
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It's real hard to see up in there. There are two ceramic pcs; one at the front and one at the back and in between those is a mess of steel wool. You can see a small amount from the rear of the pipe but not much.