1988 300E Starts When it feels like it??? - PeachParts Mercedes-Benz Forum

JohnnyV · #1 09-20-2004, 08:15 PM

Well, here is the details. I have been able to nail down a repeatable condition.

When the car sets over night or a long time it has a good chance to start, but if it does not get a solid start and it stalls then it is highly unlikely that it will start, until it sits for a while. A while can be 10 min or 10 hours. For the most part it starts after 1-2 hours. Once Started it runs fine.

I have bought the Mercedes CD, but I have not been able to nail down the infor that I need to trouble shoot, and I do not have more than a VOM to trouble shoot.

After Reading a few posts on hard starting, I have to clarify that I have been using the slight accelerator method for starting, but if the car tries to start, but does not make it, I'm stuck for a while. I did replace the spark plugs, and I can say it seems to happen more when it is warmed up.

So if anyone can provide any basic directions to check or common problems that may occur with these models, that would be great.

Thanks for any help you can provide,

JohnnyV

Mike Murrell · #2 09-20-2004, 09:33 PM

Lots of possibilities. I'd start with injectors leaking down. Has been talked about a lot. SEARCH facility should pull up info on this area.

JohnnyV · #3 09-20-2004, 09:45 PM

Thanks Mike,

I did see some of that conversation, and it seems logical. Basically a flooded Fuel injected car. A first for my experience. However, I will see if there is any way to verify this issue. Here is a question for all these experts out there.

I have heard people state that it wil start when it goes into cold start mode.

Is there any way to force the car into cold start mode for starting?

Thanks again,

JV

Mike Murrell · #4 09-20-2004, 09:59 PM

Johnny - I suppose you could try to fake out the coolant temp sensor, but if I read your post correctly, this issue occurs more when warm. If you provide cold enrichment to an already warm engine, would it not become flooded or at least be inclined to do so?

My 2 cents.

JohnnyV · #5 09-20-2004, 10:07 PM

Mike,

Sorry I got wrapped up into the electronic fake out solution, and lost my common sense on the basic combustion fundementals.

Oh well I am off to go pick up my car right now, because it is at my wifes work place. I hope it starts!!!

Thanks for the help,

I will keep up the fight,

JV

pesuazo · #6 09-20-2004, 10:35 PM

Possible causes:
1.- Faulty OVP
2.- Faulty Fuel Pump Relay
3.- Clogged Fuel Filter
4.- Faulty Fuel Regulator
5.- Faulty Ignition Coil

JohnnyV · #7 09-20-2004, 11:28 PM

Mr. P

Hey your right around the corner from me here in Raleigh, You want to come help me fix my car? Like you do not have anything better to do!!!

Well I got the car back from the wife's work. It started just fine, just as it always does after sitting for a while.

I will investigate your suggestions, although I have checked some, but not with the correct detail. I all but ruled out the coil, but I should verify.

Some I have not even heard of yet, so I will investigate.

Thanks,

JV

JohnnyV · #8 09-27-2004, 10:26 PM

I did verify that I was getting spark, and then I added a small amount of fuel to the throttle body and the car started then died. Therefore, I am greatly leaning toward fuel flow issues.

I replaced the fuel filter, even though the symptoms did not point to that problem, it was just cheap enough to try and it is the first fuel filter change by me on this car.

It didn't fix the problem though.

Can the fuel pump relay be bad if I hear the pump turn on with the ignition switch?

How do you check the Fuel regulator?

How do you check the fuel pumps?

Thanks for any help that can be provided,

JohnnyV

Robert W. Roe · #9 10-16-2004, 02:22 PM

I'm having a similar problem, I think.
My 300TE is taking at least 5 seconds of cranking to even think of starting; before yesterday it was just a second or two.
I've been smelling some burning electrical smell, if that helps narrow it down.
Thanks as always, Bob

nglitz · #10 10-16-2004, 08:35 PM

Read the thread "Adjusting the EHA ... " Lots of ideas discussed, Lots of good info. This seems to be a common problem, lots of common solutions discussed.

psfred · #11 10-17-2004, 12:05 AM

Fuel pump relay, fuel pumps.

You must determine why it won't start, then find out what causes the condition -- if you add fuel to the intake and it runs for a short time, you are short on fuel or pressure, you must determine why.

I've heard of accumulator failures causing this by blocking fuel flow.

Peter

Robert W. Roe · #12 10-17-2004, 02:25 AM

Thanks for the replies, guys.
I'm kinda bumming that this might turn into an expensive repair bill... it doesn't sound like this is "usually this", if you know what I mean. (If it were something that "always breaks on that model" I would buy the part from PartsShop just to save a little $$$.) Hopefully what I need is a $70 part and not a $600 part...

I guess I will trust my shop to troubleshoot the problem, since they are not ones to throw parts at a problem; they do actually troubleshoot the problem...
Thanks Pesuazo for the list of possible causes:
1.- Faulty OVP
2.- Faulty Fuel Pump Relay
3.- Clogged Fuel Filter
4.- Faulty Fuel Regulator
5.- Faulty Ignition Coil
with my luck it won't be the cheap #3 solution

... I would think that a clogged fuel filter would cause driveability problems not just finnicky starting...
Is there a fuse on the OVP that I can check?
Also, if this helps, it doesn't seem to matter if the car has been sitting overnight or for 10 minutes; all of a sudden Friday after work, she took a lot longer for the engine to fire than the last time I started her.
(I don't do much work myself on my car, but am always looking for that lucky 50 cent fix

Thanks again, Bob