engine idling is out of timing...revs up to 3000rpm and then drops to 1750rpm then back to 3000 again...

3,925

Asked by Joseph Anthony Dec 06, 2011 at 06:18 AM

Question type: Car Customization

my revs are not in sync...the idle rev rises and drops...when AC's on, it stays on 2500rpm...and when i engage to Drive (AT
gearbox), it stays on the 1500rpm idle...i checked the block and the crankshaft is okay and everything is in place...what could it
be? probabilities:
a.) clogged intake manifold
b.) defective air sensor
c.) lose-thread pistons and crankshaft
d.) loose timing belt

when in cruising speed with AC it seems to run fine but when AC's off and i reach about 140-160mph, the engine shakes and idle
is crazy...

5 Answers

65

answer is B. I guess Oxygen sensor doesn't work well.

1 people found this helpful.
3,925

yeah i had to change the sensor and clean the manifold...then took me a few tweaks to fine tune the idle coz it was a bit higher than the desired rpm...

Your Answer:

CarGurus Experts

  • #1
    Gene Arnett
    Reputation
    7,370
  • #2
    Paul
    Reputation
    6,800
  • #3
    Rowefast
    Reputation
    6,740
View All

Find great deals from top-rated dealers

Search

Content submitted by Users is not endorsed by CarGurus, does not express the opinions of CarGurus, and should not be considered reviewed, screened, or approved by CarGurus. Please refer to CarGurus Terms of Use. Content will be removed if CarGurus becomes aware that it violates our policies.