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'86 190E 2.3 8vlv
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Discussion Starter #1
I have been fighting an intermittant no-start problem, which I am pretty sure is a fuel pump relay.

When it doesn't start, I don't hear the fuel pump come on, but I can remove and reinstall the f.p. relay, and then it does start.

This makes me think that the problem is corrosion on the terminals of the fuel pump relay and the corresponding socket.

Is this the only possible diagnosis?

If it is indeed the problem...how to stop this from happening again?

What is the best way to clean the terminals and corresponding sockets on the car side?

To keep them clean, is it recommended to add electrical grease after they are cleaned?


If it's OK to piggyback two questions in one post...

The other problem I'm having is a rough idle and blowby. The idle is smooth until the engine is warm, then gets rough. By rough, I mean that it is smooth for one or two seconds, then sounds like it is cutting out for a split second, then ok again, etc.

Is it possible that this is related to difference in compression (#1=170psi, #2=170, #3=175, #4=150)?

Is it possible that the fuel pump relay is going, and shaking it up gets it going again, and that it is also causing the rough idle?

If not, what to do?

I recently replaced the valve cover gasket...it is possible that I did something to the recirc. outlet on the cover? If so, how to fix/clean it?

Any ideas?

Thanks,
Joe
'86 190E 8vlv auto beige
 

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'86 190E 2.3 8vlv
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19 Posts
Discussion Starter #3
NewMBOwner - 4/21/2005 9:56 PM

I may be having the same problem. What does it sound like when the fuel pump comes on?
When you first turn on the ignition, the fuel pump comes on for about 1 second. You should hear a whine sound coming from under the rear seat (or thereabouts).

If no sound, you probably don't have fuel. You should check the relay (not sure how yet), or the pump itself.

Joe
 

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91 190E 2.3
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41 Posts
I fixed mine and it never comes back for months now.

Symptoms:
1. Bad Idling.
2. Stalls when stop and go on freeway.
3. Finally couldn't start, keep cranking and trying to start.

http://www.freewebs.com/ltooz/91190e.htm

Try this and hope this solve your problems.
 

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joebob2,

You should really go check out ltooz's link, he has a great tutorial on how to possbily fix your no-start problem.

ltooz, great job on the website link. If you do any other maintenance or repair please document it like you did for the no-start problem and please post it on your website. That info was great, lots of pictures and annotations.

Great stuff.
 

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'86 190E 2.3 8vlv
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19 Posts
Discussion Starter #6
Update:

The fuel pump relay died, but the good news is that I was advised that it could be repaired, so I took it apart and inspected it. Sure enough, there was a broken solder joint. I fixed it and put it back in...started right up.

I'm not sure how long it will last...there is evidence of excessive heat which caused the solder connection to break, but if the root problem is elsewhere in the car, a new one would still have the same problem.

I took pics. They're here...
http://www.benzworld.org/gallery/showlink.asp?CatID=12972&parentID=36&subname=joe_86_190E&parentname=


About the bad idle...
Itooz...nice work on the fix and pictures. Here;s what I now plan to do.
1. I'll clean the throttle body and butterfly. Not sure how, but maybe I'll try brake cleaner first.

2. I'll check the 5/32" hose and see what's up with it.

3. The black 3-branch hose is already new.

4. I'll try to clean/replace the
 
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