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Discussion Starter #1
All,

I've tried everything I can think of and have been suggested to do and the thing still will not run for more than 30 seconds.

Replaced:
Plugs
OVP
Fuel Relay
Fuel Filter
Voltage Reg.
New Gas

and a few more things I am sure I've forgotten.

Since I started it and got it running, it's been the same issue over and over. It'll start but cannot handle a load or will stall if rev'd or idling for a minute. It seems that something is stopping the gas to flow into the engine. It's a smooth idle on a cold start, then it dies. subsequent starts yield less time it'll run. I don't want to quit, but what else can I do? What am I missing?

please, any ideas...:surrender:
 

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Hmmm maybe someone has suggested it but it's not on your list.

FUEL PUMP/S

If its dying when you give it some gas or when the amount in the lines dries out and the fuel pump is not churning.....

Worth a thought
 

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Or just the opposite, too.

If its all gas and no air (overly rich gas mixture) you are gonna flood -- stalling the motor as well. I take it there are no fault codes pointing to the o2 sensor, right?
 

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Discussion Starter #4
I don't have the ability to read any codes, but it does seems to be a flood type reaction more so than an air. Just before it dies, it picks up a bit. maybe a few hundred RPM's and then kaput. It just feels flooded at times.

other issues, coolant leak and I just noticed the strip fuse was blown. and while the tank is nowhere near fuel, it won't accept anymore fuel. it's like a giant bubble is in the tank. Don't have any idea if that correlates, but worth mentioning.

Also, the vacuum lines are hardly the best connected and could be a cause. But it's the same pattern over and over. start off with a good few minute idle. die. then each start thereafter the idle last shorter and shorter.
 

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the air flow sensor on the 300E 2.6 we were given was so gummed up, it would stick open, and flood the motor. there's lots of things that can cause issues. but your symptoms do sound like crappy fuel pumps or plugged fuel filter.
 

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Going to go back to the fuel pump idea - can you hear them running ?
When you first turn her on - before you crank - you should be able to hear them ticking over. Have a look up the back if you can't hear them from inside.
It really sounds to me like they are loading up pre-start and then cutting out.

Another though - have you checked the inside of the tank for crap that may be floating around in there and cutting out the fuel supply ?

And and while your at it - see if you can lay your hands on a fuel testing kit.
It could be you've got some water in there as well !!
 

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that is odd.

That's really odd about the fuel tank not being able to fill. I know with my FI vehicles the gas cap needs to be completely screwed on ( and a few clicks for extra measure) to get the proper environment for the system to operate. With this odd gas tank description I would take a good look there and work forward.

I have never heard of such a problem, btw. Its really odd. Like something at the filler neck of the car moved or broke and is forcing the gas pump nozzle to back fill and shut off.

If something like sediment did let loose in the tank it could be plugging the flow as it accumulates at the fuel filter/coupling in the tank. Again, I think its worth taking a look there.
 

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Discussion Starter #9
I should clarify. It took gas up to a point. About 5 gallons on what we knew to be an empty tank. It's all so very odd.
 

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It would be better for everyone if you would quit starting new threads on this same topic. You're up to 3 by my count. If we could all gather at the same thread, we might be better able to put our collective heads together and find a solution quicker! Just update and bump your original thread please!

Who's with me on this?
Regards, Eric
 

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How long have you had the car ? someone may have put something in your tank which reacts with the fuel.

It sounds like a chemical reaction ???
 

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It would be better for everyone if you would quit starting new threads on this same topic. You're up to 3 by my count. If we could all gather at the same thread, we might be better able to put our collective heads together and find a solution quicker! Just update and bump your original thread please!

Who's with me on this?
Regards, Eric
Not a bad idea. I think I doubled up on my own suggestion:confused:.
 

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If you suspect fuel delivery issue, there's a way to check for fuel pressure at the fuel distributor. There are two ports for checking high and low fuel pressure. Great article by ps2cho at http://w124-zone.com/articles.php?article_id=28

If the IACV is suspect, it can be bypassed quite easily. I don't know if you mentioned it already but did you inspect the IACV for proper operation?

Hang in there!
 

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BTW, I agree with the suggestion that it may be the in tank fuel screen/sock. (I don't remember which one of these 3 threads the suggestion was made in though. Maybe it was this one!)
Regards, Eric
 

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The codes are only for AC and SRS Supplemental Restraint System on the 89 300E. But you could put a multi-meter on the X11 diagnostic socket and see if it is reaching closed loop and fluctuating the duty cycle rapidly; which could also give an indication of the O2/lambda sensor working.

I'm with Eric too, the other thread shows you testing components and above you have replacing components. Did you replace the fuel pump relay with a brand new one?

You may need to find another running vehicle that you can swap some components out with like the EZL (Electronic Ignition Control Unit) and the CIS-E control Unit.

You mentioned you took the cable off of the battery while running and that made me wonder if other components may have been affected by that like the OVP relay. Did you replace that before or after?

Anyway, look at this diagram and see all the components that need to be working together:
Ignition 113

And then my last thought on this tonight is that the fuel mixture could be messed up and could possibly be corrected with a slight turn of the adjustment. For instance if the engine is running in open loop/default and the adjustment is set so it runs at idle then when you accelerate the fuel mixture changes too much so it is now outside the 14.7 to 1 ratio, it will not ignite.
 

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This may have already been suggested in one of the other threads but was all of the old fuel removed when this project began or did it have a chance to contaminate everything first?
 

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Discussion Starter #19 (Edited)
my apologies..for the triple posts...

I did post this subject prior, but as one may look back, neither received the attention that this one thankfully has. My apologies for that. I should have updated my progress rather than create a new thread.


I got to the car threee weeks ago. It had been sitting for at least a year which I found out last night.
It was taken to a shop and my neighbor was told it would be a $6800 repair. 90% of which I have done or is not necessary per my inspection. The list of items to be fixed do not include anything that requires finesse. i.e. vacuum, relays etc. The water pump does work. The fuel pump does work.

-OVP is new and was installed after i tested the alternator by pulling the battery wires
-fuel relay is brand new
-gas tank was drained and cleaned by the shop and new gas was put in, maybe two gallons prior to me getting to it. i've since put in Lucas Tune-up in a bottle and gas treatment and at least 2-4 gallons of new gas thinking that there was some crud left over. I started to add more fuel because I wanted to up the gas to crud ratio if there was crud. When I hit the wall on that it was suggested that I change the fuel filter which was not near the PITA that I thought it'd be but did nothing to solve the issue.
-changed the fuel filter this weekend
-new voltage regulator last night
-listened very closely to the fuel filter and it is still engaged while the car runs, dies, and prior to full start.

I will try the code reader and the other tests suggested here. I believe it's something simple and small. The exact behavior of the car(cold start longer idle, subsequent starts shorter idle), no matter what I do, leads me to believe it is temperature related. I can take a photo of the engine and perhaps y'all call see something I am missing? I feel the vacuum lines are not right. Would a pic help? A video?

Thank you all.
 

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Discussion Starter #20
If you suspect fuel delivery issue, there's a way to check for fuel pressure at the fuel distributor. There are two ports for checking high and low fuel pressure. Great article by ps2cho at http://w124-zone.com/articles.php?article_id=28

If the IACV is suspect, it can be bypassed quite easily. I don't know if you mentioned it already but did you inspect the IACV for proper operation?

Hang in there!
every time I click on one of that sites links, it shows up as dead or without any content? is his site still working? Am I missing something?
 
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