Dear all:

Is there a relationship between a high idle in park or nuetral, @2000 RPMS, with a vacuum leak? For example, a few weeks ago I noticed a hissing noise from the trunk of the vehicle after I turned it off. I assume that it is a vacuum leak in the central lock system. (have not had the time to investiage) But, lately the car in park or drive, when warm/hot, idles at 2000 RPMs. It never did this before.

Can someone direct me where to start my investigation?

Vehicle:
W201
1988
190E
2.3L


Thanks,

Iggy

__________________
Insanity: doing the same thing over and over again and expecting different results.

2006 - Suzuki Gran Vitara (2.0 L fully equipped) Like this car so far except for trying to put on the seatbelt.
1988 - 190e - 2.3L - 172K miles (It now belongs to the exwife)
1999 - Chevy Blazer LS Fully Equiped - killed it June 2006
2001 - Honda Civic EX - 68K miles (sold June 2004)
1963 - 220S - Dual Carb 6 cyl. (sold)
1994 - Yamaha WaveRaider (fun to ride)

Any vacuum leak related to the engine will often cause a high idle condition. I had one on my 450SEL and sealed it at the vac hose juncture with Red gasket sealer; the idle dropped to normal immediately. The vac door lock system would not normally create high idle -- since it is activated by a separate vac storage system that should have a check valve in it, but if the lock vac leak does have a DIRECT connection somehow to the engine vacuum systems, it could cause idle problems. Check all the vacs and seal them or replace the hoses...... BC

__________________
Ben Harrison Carter
1999 Mercedes ML320 87K
1992 Mercedes 300CE 89K
1995 Corvette 29K -- Sold Dec 09
1989 Mercedes 420SEL 99K -- (Sold 4/08)
1968 Mercedes 230S (106K) (Sold 9/06))
1976 Mercedes 450SEL 130K (Just sold - 06)
1961 Mercedes 220Sb (sold years ago)

Engine speed is absolutely determined by the amount of air taken in. Fuel only makes it work. A vacuum leak will increase the speed unless it ruins the mixture so much that the engine runs poor.

Always remember that the speed is determined by airflow and fuel in the right quantity allows it to happen. More fuel it runs slower less fuel it runs slower.

__________________
Steve Brotherton
Continental Imports
Gainesville FL
Bosch Master, ASE Master, L1
33 years MB technician