I replaced the OVP, now what.....
 

OK, we're talking about the 1987 190E 2.6 w/135k miles. For a couple months it was stalling, but would restart after 3-4 seconds of turning. Yesterday it stalled and wouldn't restart. After an hour it would. Since I needed to have my car operational ASAP, I had to go to the dealer for the OVP and $100 later it was mine. Install took a quick 2 minutes, and it started right up. After a quick 1 mile ride, it stalled again, but is re-startable (after 3-5 seconds of cranking) .

The old OVP had a part number of 201 540 32 45 and had only seven pins; the new one has a part number of 201 540 37 45 and has nine pins (the plug does accept 9 pins). I assume the new OVP is compatible. It is the same size and has the correct bracket.

So, what should I do next? I don't feel like dumping $100 here, $100 there. FYI, I had the ignition coil replaced 3 years ago and the o2 sensor replaced about 4 - 4 1/2 years ago. I imagine it is a relay problem of some sort. What do you guys think?:confused:

I would check the fuel pump relay and the crank sensor. I have had alot of failures out of those components.

How do I check the fuel pump relay or the crank sensor to see if there is a problem? I'd rather not just replace something and hope it works.

My suggestion is to take the car to a reputable shop and have them diagnois the problem and then you won't have to rely on "trial and error"

Part vs. Labor?
 

I don’t know because I’m an amateur but if you can buy a fuel pump relay (rebuilt) for $60 the diagnosis of this part cost’s more than the part itself. I looked at the procedure in the manual and it takes a special tool to really plug into the relay.

Are there any other symptoms?

Steve
’85 500 SL Euro

It was the OVP!!
 

Maybe it took a couple days to get set. I don't drive the car too much and after a couple spins, it seems to run OK now. So, it was worth the $100 and 2 minutes time. It has stalled only once in the past few days, which is nothing compared to what it was. Sometimes it wouldn't even start up.

You may still have another problem. I don't think there is a "break-in" period for the OVP...it either works, or it doesn't. You are still having stalling problems, though less frequent.

The OVP may have solved a number of problems, but I still think something else is also amiss.

Keep driving and see what happens. Also, if you don't drive very frequently, you might replace the fuel filter. It is cheap, requires no diagnosis, and from some of the threads I've read, solved a few problems as well...

Uhh, I don't mean to sound stupid, well I guess it is too late....
What does OVP stand for? :confused:

OVP = Over Voltage Protection

Helps to prevent damage that would be caused by an electrical spike.

Where is/are the fuel filter(s) on the 190E 2.6?

I'd like to do mine since as you said, it's cheap and I'm not sure when it was last done.

Mike McKinney

2.6(M103) fuel filter location

Should be just to the left of your right rear wheel by gas tank. May be covered by a box-like plastic shroud held on by 3 bolts.

For a diyer, this task is more easily performed if you back the car up on ramps. You do not have to back up all the way, just enough to give you clearance to get underneath. Chock the front wheels after the car is on the ramps. Disconnect battery ground strap B4 you begin. The procedure is outlined in the Mercedes-Benz Maint. Manual 1981-1993. The maint. manual is part of the CD-Rom.

If you experience leakage after replacing the filter, snug down the mounting hardware some more and be sure to use new copper gaskets on both ends of the filter.

I appreciate that Mike.

Thanks very much

Mike McKinney