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garthfan · Joined: 28 Feb 2004 Posts: 226 Location: Manchester, NH

....a 2.5L n/a???

As with any engine fresh from a rebuild, I'm now in the process of sorting out the little things. The only thing I'm really unhappy with now that the car's back up and running is the idle.

In a nutshell, she's pretty rough sitting at idle now where she used to be nice and smooth before the rebuild. Soon as I hit the throttle, though, she purrs like a kitten. I've checked the vacuum connections and they all seem to be pretty well sorted out, so now I'm wondering if I could have set the timing slightly different.

With the flywheel sitting at a perfect TDC, anybody have an opinion as to where the camshaft-gear marks should fall? Should they be dead-on to each other as well? Or maybe a hair off one way or the other???

Thanks!
_________________
1987 924S - Was a daily driver...now it's GONE! *sniff*
1986 944 N/A Guards Red
1996 VW Jetta Grocery-Getter
1995 Saab 900S Winter-Driving-Feeling-of-Security-Vehicle

Sleykin · Posted: Sun Nov 14, 2004 2:59 pm Post subject:

If the mark on the cam is within half a tooth it is ok. They rarely line up perfectly. Did you set the throttle buterfly to the specified gap and then set the TPS? After that is correct you would then bypass the idle stabilizer valve and adjust the idle air bypass screw to 900 - 950 RPM hot and then turn the ISV back on. After that initial setup the DME controls everything.
_________________
Glenn Neff
Medford, OR
87' 924S

garthfan · Joined: 28 Feb 2004 Posts: 226 Location: Manchester, NH

I didn't bother to mess with any of the throttle settings either at the "butterfly" or the TPS because I really didn't do anything to them during the rebuild other than disconnect them.

What do you recommend as the best way to reset them??? My Haynes covers the testing of the TPS, but doesn't say anything about setting it.
_________________
1987 924S - Was a daily driver...now it's GONE! *sniff*
1986 944 N/A Guards Red
1996 VW Jetta Grocery-Getter
1995 Saab 900S Winter-Driving-Feeling-of-Security-Vehicle

Sleykin · Posted: Sun Nov 14, 2004 4:52 pm Post subject:

Clark has a nice proceedure for it http://www.clarks-garage.com/shop-manual/fuel-08.htm
There is also a starting/running troubleshooter there, but I would start with the idle adjustments first. ... It fixed mine after the headgasket job.
You may need to pull the throttle body and clean the gunk out too.
_________________
Glenn Neff
Medford, OR
87' 924S