Engine Shakes after antilock sensor went on??
 

Is it just a coincidence. My 1987 190E 2.6 engine started shaking while idling after the anitlock sensor came on. Anyone have an idea what might have cause the shaking? It was OK before that.

Gee, I get to be first.

It is the overvoltage protection relay or the fuse on top. I'll bet on this one.

Additional info.
 

Steve,
Thanks for your suggestion. I'm not really a mechanic and need some direction as to what is or where is the overvoltage protection relay. Also I forgot to mention that when I first start the car in the morning, like today. I would have to step on the gas 2 or 3 times, then start it. The car would shake and almost stall. I press on the gas and feel some hesitation, as if choking. It eventually stalls. I have to start it 2 or 3 times with the same routine until it the hesitation goes away. I may have multiple problems, but don't know where to start troubleshooting. Replaced fuel filter, but also thinking about fuel pump. I've also read in this forum about possible fuel injectors clogged.

OVP
 

Look on the firewall, not sure which side on your car (it's near the master cylinder on the 560). You'll be looking for a silver module with a red top, it also has a clear flip top - very distinctive, only one like it. Under the clear flip top you will have one (possibly two if the unit has been changed) 10amp blade type fuse. Check the fuse it may be blown, if not spring for a new OVP ~$50.00 or so.

I have the same problem with my 560SEL!! It has been shaking like crazy lately and I've replaced my OVP relay thinking that would help (although the fuse was still in good shape,I figured that maybe the relay itself was bad and replaced it anyway-glad I didn't toss my old one because its probably still good).She always starts right up though,and has never stalled.I just came back from lunch and noticed that pulling off from a light that as I push the accelerator, she shakes and even though I'm barely moving, its using a ton of gas! I'm thinking of changing my spark plugs right after work to see if that helps.I hope that's what's up although its probably more... any ideas here? Secondary ignition components?

I am never one to use parts to do diagnostics, but this is a special case. You have two control systems down and it occured all at once and they have one thing in common. And that one thing is probably the number one pattern failure on your car.

The OVP relay is something like a surge protector for the expensive controls units: engine management and ABS. The logical test would be to check power supply to both control units. This would not be an easy task. You can guess that the ABS is out if the light is on without driving. You can test the EHA current which is the output of the KE controller (and the reason you are having all the engine performance problems - no fuel control).

The OVP is behind the battery. You must remove a thin plastic shield to see all the control units and the OVP. See if the fuse is blown for sure, but if the date code on the unit is 1987, replace it.

Update
 

I found it, but there was no thin plastic shield. Should I buy a replacement for it? The red fuse is good. I'm just going to go ahead and go to my local MB dealer and purchase one. When I pulled up the OVP it seems very easy. Tried to push it down and it seem its not locking. Is there suppose to be some click to lock that I may feel? It's behind some rectangular box with some heat sink on top, so I can't easily see it to see if the OVP relay is actually lock in at the bottom.

Yes, you should replace the cover. It keeps battery fumes and rainwater from the connections.

The relay just plugs in, no click, but it should be relatively hard to get out once shoved in. If you put the new one in and it doesn't fix the problem, verify that the fuse is hot (battery voltage) with a test light or voltmeter. It of course won't work without being fully plugged in.

BTW if you still have the original OVP the new one will be slightly different with an extra pin. Don't worry about it.

Update
 

The local MB dealer is going to charge 87.00 + tax. I found another place for 70.00 include tax & shipping. Should be here tomorrow or Friday. I'll post my result when I receive the part. Thanks for everyone's help. I'm glad I found this site!!!

Did you also check right here at FastLane and PartsShop?? They have the OVP for ~$60.00, with shipping figure <$70.00.

Update
 

Steve, You're the man!!! I replace the OVP relay and problem fixed. I tried to push down the OVP relay as close to the connector, but there's still a 2/16" gap. The location of relay makes it hard to get a good connection without removing other things. I just want to thank Steve B. and all those who gave suggestions. Now on the next problem, the A/C.