Running rich and rough ide when engine is warm
04-11-2006, 05:10 AM
#31
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Easy, Takes 2 minutes to check.
Just attach a multimeter to pins blah and blah of the LH connector (can't remember the numbers now, but it was posted here not so long ago and you can also check in the WSM). Conductivity test: It has to beep when you floor the gas, but not before.
As I told you previously, I've exactly the same simptoms and my WOT switch is working properly.
Good luck.
Just attach a multimeter to pins blah and blah of the LH connector (can't remember the numbers now, but it was posted here not so long ago and you can also check in the WSM). Conductivity test: It has to beep when you floor the gas, but not before.
As I told you previously, I've exactly the same simptoms and my WOT switch is working properly.
Good luck.
04-11-2006, 07:04 AM
#32
Rennlist Member
It may be that when the engine was cold and/or idle speed too high, the MAF reading might be higher.
If when engine is warm, and you sit at idle for several minutes without the MAF voltage rising slowly, then it is probably OK.
There isn't a WOT sensor as such, it is a switch on the end of the throttle plate spindle. The same assembly also contains the closed throttle switch. I've not heard of a WOT switch failing in the closed position.
LH ECUs can sometimes "think" that the WOT switch is activated, even when it isn't - this make the mixture too rich.
The only way to check this is to have the LH ECU checked out, do a LH ECU swap with a good one, or measure the idle pulse width with a 'scope.
Can you borrow a good LH ?
If when engine is warm, and you sit at idle for several minutes without the MAF voltage rising slowly, then it is probably OK.
There isn't a WOT sensor as such, it is a switch on the end of the throttle plate spindle. The same assembly also contains the closed throttle switch. I've not heard of a WOT switch failing in the closed position.
LH ECUs can sometimes "think" that the WOT switch is activated, even when it isn't - this make the mixture too rich.
The only way to check this is to have the LH ECU checked out, do a LH ECU swap with a good one, or measure the idle pulse width with a 'scope.
Can you borrow a good LH ?
04-11-2006, 08:45 PM
#33
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Thanks guys!
I won't have a good LH to borrow close by, i think my only other option is to have the LH ECU checked out. I will contact a few mechanics and the porsche dealer to see if they can check out the LH. Can i pull out the LH and take it to the shop, or do they need the car as well?
Thanks again!!
Ken
I won't have a good LH to borrow close by, i think my only other option is to have the LH ECU checked out. I will contact a few mechanics and the porsche dealer to see if they can check out the LH. Can i pull out the LH and take it to the shop, or do they need the car as well?
Thanks again!!
Ken
04-12-2006, 03:02 PM
#34
Rennlist Member
Garages don't have the equipment to test an LH. I can check it out for you...
easiest way is to swap, you can use any LH ECU, S4 onwards just to prove where the problem lies.
Perhaps someone on the list will agree to try your LH in their car ?
C'mon, guys !
easiest way is to swap, you can use any LH ECU, S4 onwards just to prove where the problem lies.
Perhaps someone on the list will agree to try your LH in their car ?
C'mon, guys !
