Hey guys, posted this in the general tech forum, and got no reply. maybe someone here can help. The idle on my (126) 86 420 SEL seems to be hunting. It will speed up to 1800 rpm, and stay there. After a while it will return to normal, but then do it again, even as I'm driving along. When this happens the SRS anti lock light also comes on. It is an intermittent problem, but can be dangerous, as I never know when it will happen. If not careful when in traffic, the added rpms can cause the car to lunge forward. Any ideas?

 

try to check the alternator when the car dont have 13.8v the abs and srs will shut down and the light will on.
try to check the cold start injector is leak gas ....

 

Hey, I solved the problem with the help of another MB website. It was the OPR Relay that was bad. This seems to be a usual problem. When I changed it, all symptoms disappeared.