Idle problem with a 91 Integra it spikes at start up to 3000rpm then jumps between 1200rpm and 2400rpm?

Question

i unplugged the hose to my MAP sensor and it idles fine after that i just cant drive it far unplugged. Any thoughts does that just mean its the map sensor? a new one is like $330.00 cheaper route? please let me know

Answer 1

Sounds like it could be one of three things. First, check your vacuum, as you could have a leak. Should be 18-21 pounds. Likely source - power brake booster. Second, the fast idle valve may be stuck. It's on the intake manifold and looks sort of like an EGR valve. Rap on it with a screwdriver handle and see if it unsticks. Third, check the idle s***w on the throttle body. They are known to back out to the point of falling out. Be sure to reset your computer after the car's fixed by pulling the backup light/flasher fuse (located on left kick panel) for 10 seconds, then reinstalling. Hope this helps.

Answer 2

Could be some carbon deposits.

Answer 3

ertetet

Answer 4

nwt sure

Answer 5

Could it be the timing belt?  That's a large range (1200-2400) over which to be idling.

Answer 6

map sensor, or, fuel pump.  Since you made no mention of stalling, the map sensor is the most probable cause.