High idle in 97 850 na

ahuggard · Post by **ahuggard** » 07 Jan 2008, 16:14

I currently have a high idle--around 1000 rpm--and poor gas mileage. Before I go messing around with the throttle positioning, is there something I should check? I'm thinking possibly:

clean throttle body
pcv/flame trap maybe
vacuum issues?

Thanks,

Alex
850 na wagon 172k

Post by **MadeInJapan** » 07 Jan 2008, 16:24

Throttle cable is not unwinding from around the spindle (check under your throttle cable cover) is a possibility as well.

ahuggard · Post by **ahuggard** » 07 Jan 2008, 16:30

Thanks, MIJ--I'll check as soon as I get some free time (maybe not till the weekend).

Alex

Post by **MadeInJapan** » 07 Jan 2008, 16:53

Oh, and definitely vacuum issues. Do you have any trouble codes or is your check engine light one?

ahuggard · Post by **ahuggard** » 07 Jan 2008, 18:30

No trouble codes (fixed the P0410-air pump replacement) and the CEL is not on. The car is relatively new to me and, beyond some of the standard maintenance (oil change, timing belt, etc), I'm not sure what preventative stuff was done.

vlv850 · Post by **vlv850** » 07 Jan 2008, 21:17

I had the same issue a while ago, and it was a vacuum issue. Check the black soft rubber connections around the throttle body tree, and also the one that is a little difficult to see on the timing belt side of the engine that is near the thermostate area.

Post by **MadeInJapan** » 07 Jan 2008, 21:41

Yes, the rubber connections...the ones we call "elbows." The one slightly under the power steering pump on the side of the engine is one that is hard to see and often is the culprit when there is a leak but you can't find it. Also, just a tip on how to find these...spray some carb cleaner with engine running in the suspected area. If you have a leak, the cleaner will get sucked in and cause the engine to surge slightly.

ahuggard · Post by **ahuggard** » 07 Jan 2008, 22:13

Thanks. I forgot to mention that when I start the car, the engine revs up to around 1700 rpms before settling in at 1000 rpms. Does that help with diagnosis?

Right now, my plan of action is to clean the throttle body, check the spool, and check for vacuum leaks.

Thanks,

Alex

Post by **MadeInJapan** » 08 Jan 2008, 04:46

ahuggard wrote:Thanks. I forgot to mention that when I start the car, the engine revs up to around 1700 rpms before settling in at 1000 rpms.

Actually that's really normal especially in cold weather. Our old 850 did this all the time.