|
My wife drives an 85 240 wagon, we got it last summer. We love the thing to pieces, but it has a few problems.. I work on my VW waterboxer van all the time, but this is a completely different animal!
It dies when cold. Starts right up (always starts great), runs for a second, and dies. After goosing it and starting it a few times it runs OK. It's not a constant trying to die, it cycles high and low idle about every 5 seconds. If you drive it like this, it does make good power and goes OK.After a minute or two it starts to idle OK. Sort of "snaps" into this mode, like it's a computer thing.
It has no power when hot. Idles OK and at the correct speed always. It revs up great, engine sounds fine, but when driving it off the line, it accellerates very slow. Not like it's completely broken, but bad enough to be somewhat dangerous making left turns in Seattle. My wife says it's a good thing Volvos are so safe because she's going to get hit! :/
Troubleshooting stuff I've done...
Removed and (really really) cleaned throttle body, replaced gasket. No change.
Replaced plugs, cap, rotor, wires. Helped somewhat.
Replaced all vacuum lines. No change.
o2 sensor: I've tried two. The original one meters about 220-500mV, 220 at idle. Bought a new one that meters 80mV at idle and 800mV when revving. Both behave similarly performance-wise. If competely disconnected, the car runs FAR worse. I could steal the one out of my old L-Jetronic VW to see what happens in the volvo, I think they're the same bosch unit.
AMM: If disconnected, the car runs FAR worse. The element measures about 4 ohms. It seems OK.
LED Lambda light check gadget: The LED remains off all the time, the Lambda cycling described in Bentley does not occur regardless of how the screw on the AMM is set.
Idle test point (white and blue test connector wire): Grounding this doesn't seem to affect anything at all. Like it's not connected (but it is, I checked on the computer's connector).
One funny thing I noticed is that if I disconnect the vacuum line from the fuel pressure regulator, there is no change. But if I disconnect and plug that line, the idle speeds up a lot like the regulator is leaking air perhaps? No fuel leaks at all. I don't have a fuel pressure guage. I suppose I could go buy one.
Sorry for the long winded post, I've just been banging my head on this one. VW digifant seems a lot easier so far :) Thank you!
Lucas in Seattle
|