revving idle

blenkusha · Post by **blenkusha** » 28 Dec 2010, 18:51

Hello,

I've been working on my '93 Volvo 240 B230 quite a bit recently. (With much help from this group!) I've replaced the head gasket, timing belt and radiator.

The car seems to run fine while driving - maybe lacking a little power. However, when the car idles it starts a little high and gradually raises until it reaches the same point then drops back down to the pace it started idling at. It also is not as fuel efficient.

I did have a difficult time getting the timing down and am wondering this is a symptom of the timing being slightly off. Before I take it apart again I wanted to see what other possibilities could be, or possible starting places.

Thanks again for all the help!

Kmaniac in California USA · Post by **Kmaniac in California USA** » 28 Dec 2010, 20:22

blenkusha wrote:I did have a difficult time getting the timing down and am wondering this is a symptom of the timing being slightly off.

Could you be a little more specific and descriptive of what you mean by this statement?

If, by chance, this means that you had to retard the distributor to it's full limit to get the ignition timing mark to it's proper spec' on the timing cover scale, you may have a failed vibration damper that caused the outer pulley (with ignition timing mark) to slip in the advance direction relative to the center hub. If this truly did happen AND you tried to adjust the timing mark to anticipated spec', the timing would truly be retarded, accounting for poor idle and lack of power.

When this happened to my 740, the smog man measured my ignition timing at approximately 60 degrees before TDC and no adjustment could get the timing mark back to the scale. Only when I verified and replaced the vibration dampener/pulley with a new one was I able to properly set the ignition timing.

blenkusha · Post by **blenkusha** » 28 Dec 2010, 22:14

Well, at first I had my marks lined up wrong. I didn't do anything with the distributor. What I mean by that sentence is, if I lined up the timing belt and things are off by a few teeth, could something like that cause the idle problem?

One thing I forgot to mention, the check engine light is on. But when I check the diagnostic it always reads 1-1-1, which if I'm right means everything is ok.

Thanks for the help.

Post by **billofdurham** » 29 Dec 2010, 11:20

If you have the timing belt off by even one tooth it will cause problems with the running and the idle as the timing will be out.

Did you check both fuel (socket 2) and ignition (socket 6) diagnostics?

Bill.

blenkusha · Post by **blenkusha** » 29 Dec 2010, 18:50

Since this is the first time I've done all this I kind of figured I'd have to recheck the timing, but it's cold here and I've been trying to avoid it.

I did check both socket 2 and socket 6. Think I might reset it, see if it comes on again and if it reads anything this time.

Cheers.