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CHP1884
03-25-2007, 08:56 PM
Q. I just replaced the Idle slide valve on my 86' 420SEL. However, it idles a little high now.(1400rpm in park; 950rpms in drive) Hence, what adjustment should I make in order to bring the idle down to normal range.(750-900rpms in drive/park) Otherwise, the car drives fine.

Note: Interestingly, before purchasing a 380SE sometime ago, it had a high idle problem and my mechanic replaced a blown fuse that controls the idle in the main fuse box. And the idle returned to normal. Could this be the solution? Also, he checked the idle by using a special tool that looked like a long flat-head screwdriver to check the idle adjustment in the top of the air box. Thus, could this also be the solution? I appreciate feedback on this issue. Thanks!

BENZITCH
03-26-2007, 11:14 AM
Have you checked the OVP fuse?
Bruce
PS It is located on the firewall just to the left of the brake booster looking at the car from the front.

CHP1884
03-26-2007, 08:22 PM
Thanks for your feedback. I stopped pass my mechanic's shop and he showed me that it was the OVP relay. Hence, I ordered a new one that should arrive on Thursday. Next week, this one goes to the shop to be repainted. Thus, I can't wait to see the results.

Gmazzini
03-26-2007, 11:42 PM
You have a very nice car. Just keep a close eye on the timing chain.

Jack