Crank, but no start, '88 190E 2.6
 

It has spark, but I cannot hear or feel the fuel pumps energize briefly when the ignition switch is turned on to just short of the start position.

The car has been in storage for the last 10 months as it has been many times in the past 30 years, but this is the first time the engine wouldn't start right up after hibernation. The fuel tank is full.

I suspect the fuel pump relay. I believe it's the first rectangular section relay behind the battery, just ahead of the KLIMA relay. I want to pull it out to check pins, but can't get it out. There is a locking tab on the front side, that I am able to disengage, and I suspect the rear has one too. Since the KLIMA relay is nearly touching I've been using a .035" feeler gage between them to try to unlock the tab, but no luck.

It's the original part with the following ID data:

003 545 00 05

KR0003 KPR

05 8956 70

Is this the fuel pump relay, and does anyone have a trick to remove it?

Also, I recall there's a way to short a couple of pin receptables with the relay removed that will energize the fuel pumps. Does anyone remember this, and maybe have link?

Duke

Found a good thread... jump pin receptacles 7 and 8, but I still need to get the damned thing out.

http://www.peachparts.com/shopforum/tech-help/416104-help-fuel-pump-power.html

Frank Reiner, if you're out there please check in and let me know if I'm working with the right relay and how I might get it out.

Duke

D:

That is the FPR. It may be necessary to remove the Klima relay first.
The pins of the FPR are rather a tight fit in the sockets, so quite a pull
with some rocking of the relay is required.

Key in run position, do you have power to fuses 6, 7 and 8? On my '91 300TE a similar setup, I didn't and it was the ignition switch, new switch and done

Good luck!!!

Thanks guys. I've got a couple of days to work on it. Pelican is about 10 miles away from me, but I won't be able to get there until Tuesday.

Merry Christmas!

Duke

Duke, If you don't have power to those fuses, a jumper from the battery to the fuse terminals will allow it to start in case you need to move the car.

Good luck!!!

Success! I removed the battery to get a better angle and grip on the FPR, really wiggled it back in forth as far as it would go, pulled as hard as my grip could offer, and it popped out.

The pins and receptacles looked like new... no corrosion or damage.

... made a shorting plug from a short piece of wire, connected it between receptacles 7 and 8 and the moment I connected the battery I heard the fuel pumps energize. It was a little reluctant to start, but once it finally fired and I got it to 2000 revs it stabilized, so I eased off the throttle, and it settled into a smooth 1200 RPM idle, which is about right for the 60 degree ambient temperature.

I'll be going down to Pelican early tomorrow morning to pick up a new relay, and that should be the fix.

Thanks Frank and Sugar Bear for the help.

Duke

Duke, Do you have 12V to and through fuse #8?

I didn't check that because when I shorted the #s 7 and 8 pin receptacles I heard the fuel pumps energize, then started the engine and took it for a short ride around the neighborhood to check that everything worked, and all was okay.

Yesterday morning I arrived at the Pelican warehouse in Harbor City a little before 7 AM. By a little after 7 no one had yet arrived, so I called and found out that it's not a walk in facility, but they have "curbside" pickup for previously ordered parts, but it doesn't start until 0930.

The Web site showed three FPRs... Mercedes, Striebel, and Uro. I wanted the MB part but both the MB and Striebel parts were out of stock, and the nearest Uro part was in San Francisco. It shipped to my house yesterday, and I hope to have it this week.

The Uro part was a little over half the price of the MB and Striebel parts, but Uro has a spotty reputation.

If anyone has installed a Uro fuel pump relay can you tell me how long it's been installed, how many miles, and if it's performed okay?

I know that FPRs can fail due to cracked solder joints, so I'll be taking the dead one apart to see if I can repair it and keep it as a spare.

Duke

Hi Duke, we sell a few hundred of Fuel Pump Relay 003 545 2405 annually, and haven't had any returned as defective during the last 12 months (our CS dashboard doesn't show further back than that), and don't see any complaints reported to Engineering during the last nine years. This relay is covered by our two year warranty, so if you have any issues just let us know.

Thanks! That gives me good confidence. I only drive my 190 about 500 miles per year now, and it's usually stored during the summer when I drive my '91 MR2.

The part left the Oakland USPS distribution center early this morning, priority mail, so I might even get it tomorrow. I'll report back when it arrives, get it installed and do a test drive.

Duke

USPS delivered the FPR yesterday afternoon, and I had the car running within a few minutes and took it for a short test drive.

Review of my maintenance records revealed that the FPR was replaced on warranty, but the listed part number on the RO is NOT the same as the failed part I removed.

I'll start another thread on this issue.

Duke

Excellent, glad to hear!

The removal of the fuel pump relays from the cradle is very hard.This is due to tabs on the side of the relay that slot in to the main plastic frame .I replaced my relay but before i did i removed the edge off both tabs on the new relay to make it easy to remove it ...but dont do it till you get it to work first or the shop might not take it back if faulty