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1989 190E 2.6L Engine Turns Off Mid Drive

1418 Views 57 Replies 9 Participants Last post by  plinker17722
Hello,

So I know there has been a lot of posts about this and I have tried to search and comb through those posts but I am not sure what to do from where I am with this car.

To start off, I recently purchased a 1989 190E 2.6L. Its been off the road for a couple of years and needs some TLC. When I went to check out the car, the guy had to jump it as it hasnt been started in a while, but after starting it, the engine roared to life and ran actually pretty smoothly. We went for a test drive and it was about 15 minutes and I got it up to 60 MPH.

I got it towed home as I driving behind the truck. When I got home, I was excited to drive it and I went I took it out for a drive, it sputtered and shut off. Luckily, I was able to limp it back home but had to restart the car many times. So I thought it was a fuel issue as I knew there was fuel in the tank.

I removed the entire gas tank, replaced the in-tank filter and inline filter and cleaned out the gas tank. It was really bad in there and I am really glad I went through that hellscape because it was damn dirty in there.

So, today, after installing the tank and new filter, connecting the lines and new gas I took it for a drive. Took a second to start it for the first time in 2 weeks but after than, she started right up every time! I did noticed though a weird sound coming from where the fuel filter/pump was (this may lead to what the issue is, but we will get to that).

So I took a drive down to the gas station and filled up, no issues. I then went to a drive through car wash because she really needed it. This where the problems came back. As the car was getting washed and just sat there, it turned off on me. I didn't think much of it, and started the car again, started up right away. However it kept happening with the car just sitting there. At one point the engine wouldnt start up, so I have to get the car in neutral and push it out of the carwash... Got it into a parking spot, started the car up and started to drive home, about 2 times the car stopped on some main streets and the final distance it stopped about 5 times before it finally got home.

Here is where I am a little lost on what I should do next. When I test drove the car it ran fine, but when I got it home it started stopping mid drive (same day). I replaced both fuel filters and cleaned the tank which it desperately needed. But the issue still occurs. I checked the OVP relay with a test procedure I found on this forum and it tested just fine (btw its an original Mercedes OVP relay, its date stamped with 7/5/89...) Could it still be the OVP relay?

I did mention went I started the car for the first time there was a weird sound coming from the fuel filter/fuel pump location, could that be my issue? A family member suggested that sludge from the fuel tank could be in the fuel lines.

I know these two things could easily be the issues I am seeing, but I want to make sure before I go buying parts that wont fix the issue. What else could I check to eliminate any other suspects?

To be honest, I know these are kind of dumb questions but I am just hoping to get some direction here.

PS. I have a new battery in and I do have new non resistor spark plugs, oil and oil filter on the way. I also replaced the air filter, but that was after I stopped driving the car.
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· Super Moderator
1986/1990 W126
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21,628 Posts
Welcome to the forum. Can I recommend putting your car details into your profile for us please? It's helpful for members - Complete your Profile

So did you get lucky and it was sludge and not rust in the tank?
Sounds like you did all the right things, the tank strainer does get blocked up.
I just wonder if it'll need doing again. Or, as you mentioned, flushing the lines would be a good idea.
Another thought is that the fuel pump might be quite tired after trying to suck through the sludge. If its the original, it would be difficult to find that level of quality again. Removing it and reversing the direction to backflush it with diesel can be a good rescue for an old pump.
 

· Registered
W201 190E 2.6 A/T
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18 Posts
Discussion Starter · #3 ·
Welcome to the forum. Can I recommend putting your car details into your profile for us please? It's helpful for members - Complete your Profile

So did you get lucky and it was sludge and not rust in the tank?
Sounds like you did all the right things, the tank strainer does get blocked up.
I just wonder if it'll need doing again. Or, as you mentioned, flushing the lines would be a good idea.
Another thought is that the fuel pump might be quite tired after trying to suck through the sludge. If its the original, it would be difficult to find that level of quality again. Removing it and reversing the direction to backflush it with diesel can be a good rescue for an old pump.
Will do on the profile part.

And yes, no rust at all in the tank, just sludge. I used a pressure washer to clean the tank and a lot of stuff came out but the walls were nice and clean, no rust.
Yeah, thats something I am worried about, if itll need another flush essentially which is not a fun job.

Now that I recall, the fuel tank strainer filter (that thin filter layer) was pushed in as if the pump was trying hard to suck fuel but there was so much blockage it bent in the strainer itself. I think I may follow your advice on the fuel pump and take it out to give it a good cleaning.

I just need to find a way to stop the fuel from draining out of the hoses when I remove the pump.
Also, is there a way to check the fuel lines in a way where I dont have to take all the hoses out?
 

· Super Moderator
1986/1990 W126
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21,628 Posts
Excellent point Plinker. And for the lines, you can easily flush the supply line to the fuel distributor.
The return line is a conundrum though.

Well done for getting to that tank strainer. Yes, they can get all sucked in from the pumps trying to extract fuel.

You don't have excess vacuum when you take the filler cap off do you? There is a vent valve, just a little plastic valve plugged in under the car on the way to the charcoal cannister. If this or the lines block, can create problems.

A bit of an outward woosh noise is more what you want. The valve maintains a certain amount of tank pressure if all is good.
 

· Premium Member
1992 190e 2.3 8v, 1993 190e 2.6 Sportline 5 speed
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443 Posts
If it were me, the next thing I would do is check the fuel pressures and volume. While waiting for your fuel pressure gauges to arrive, clean electrical grounds, relays, ECU pins - all electrical terminals. I recommend DEoxit.

Then I would test to see if the problem is electrical or mechanical. Pull the OVP and start the car- yes it will be hard to start. Drive the car, does it shut down still? If it still does, the problem is likely the fuel pumps, fuel pump relay or could be the fuel distributor.
 

· Registered
W124, 230E 5 speeds Manual, 1987
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616 Posts
Sudden e fine dying is probably an electrical problem since the car runs well after it atarts:

1- Crankshaft position sensor. A bad one will kill the engine when it warms up. You can check its resistance immediately after engine dies and if you got a bad value than this is your problem. You can search this forum for resistance values and testing procedure.

2- Fuel pump relay and not OVP relay. The OVP never cause a sudden engine dying. A bad fuel pump relay will break contact when it gets hot due to cracked solder joint and it will shut off thd fuel pump and so the engine.

3- Distributor cap and rotor. It will be a good idea to check all the ignition system from coil to spark plugs wires. ( Whn you washed the car there was humidity, a little problem with the ignition system will cause a non start and engine dying in humidity but it wont run very good as well as there s humidity still in. Thats Why i ruled out this scenario.
 

· Registered
89 190E 2.6 x2, 99 SL500 Sport
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2,008 Posts
+1 it's going to be either the Crankshaft Sensor or Fuel pump relay.
Over the years I've had problems w/ both of my W201s shutting off and dying. Each time it was the solder joints in the fuel pump relay going bad. I usually just get those KAE relays and they're fine.
Also definitely replace the OVP, put the newer style one w/ 2 fuses in.
 

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W201 190E 2.6 A/T
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18 Posts
Discussion Starter · #11 ·
I think the first thing I am going to do is try to run the car with the OVP relay out as I already have it out from testing it. I am hoping the engine will shut off, meaning its a fuel issue. From there I will pull the fuel pump relay and see if I can fix the solder joints. And again check from there.
 

· Registered
W124, 230E 5 speeds Manual, 1987
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616 Posts
I think the first thing I am going to do is try to run the car with the OVP relay out as I already have it out from testing it. I am hoping the engine will shut off, meaning its a fuel issue. From there I will pull the fuel pump relay and see if I can fix the solder joints. And again check from there.
OVP or No OVP your engine have mechanical injection which shall run perfectly without electronics even. Electronics are for assistance and better performance. OVP doesny cause a sudden death of the Engine. Check the itema in my post from 1 to 3 and you will be Okay I m sure
 

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1989 W124 260E
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7,990 Posts
A quick check on the fuel pump relay is to pull the relay out [ bit of a job ] they can be tight in the holder .Hold the relay in your hand , and then pins 7 and 8 you wire them together, push relay back in to the holder .. Only use the wire to see if it is the relay or not . Once you prove its the relay ...thats if engine keep running , remove wire right away and replace the relay with a new one .
 

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W201 190E 2.6 A/T
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18 Posts
Discussion Starter · #15 ·
So I went to go pull out the Fuel Pump relay, right next to the OVP relay. I found two relays installed?

One directly left of the OVP relay and one directly in front of that. From pictures and videos I have seen, I have only ever seen one.

The one is the back looks to be OEM with the mercedes logo and "6 Zyl. 12V" and the other is aftermarket, KAE.

I am a little lost here.
 

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W201 190E 2.6 A/T
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Discussion Starter · #16 ·
So I went to go pull out the Fuel Pump relay, right next to the OVP relay. I found two relays installed?

One directly left of the OVP relay and one directly in front of that. From pictures and videos I have seen, I have only ever seen one.

The one is the back looks to be OEM with the mercedes logo and "6 Zyl. 12V" and the other is aftermarket, KAE.

I am a little lost here.
So I think I may have found something. Here are pictures of the two relays. (Also my bad on the KAE one, I wiped it down with a brake cleaner soaked ragged and wiped the lettering away but it said "Fuel Pump Relay".

On the OEM relay, there was no sealant on the relay so I was able to take the cover off pretty easily. Couldnt find any broken solder points but I did find some scratches on the back and a hole in it. but no idea if thats meant to be there or not. This one has already been tampered with.
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W201 190E 2.6 A/T
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Discussion Starter · #20 ·
Little bit of an idiot, the "kilma" relay is meant for the A/C compressor. But it was still tampered with.

The KAE fuel pump relay taken apart looks pretty bad with a dark orange stand on the circuit board. Gonna look into buying that replacement.

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