1998 300TE Petrol estate stops when warm?

[macseast]

Hello all!

After years of wanting a Mercedes i finally purchased a 1989 300TE petrol estate.It had belonged to the same person for the last 11 years and although it has 160k on it it is in very good condition.
However when i bought it the seller told me he had problems with it cutting out when warm but he thought it was down to old fuel because the car was in storage.Anyway on the test run all was ok so the money was exchange.

I have driven the car with no issues up until this weekend when on a short trip and parking up for 20 mins the car would turn over but not start? I left it for an hour came back and it started perfectly and drove home.Yesterday i went on the same journey to get fuel and left the engine running,When i put the car into D it stopped again and would not start.

I left it again for a couple of hours and it started perfectly.Can anyone give me any ideas to what is wrong as i have no faith in the car now and i dont want to end up buying parts i dont need.

On both occassions i believe the engine was at 80 degree's and fully warmed up.

Any help gratefully received

 

[Will]

First thing to check on an M103 - especially if it's been standing - would be the distributor cap and rotor arm.

If it's tatty/cracked/corroded/damp etc clean/replace it as needed and then see how it goes.

Then look further if no joy, IMHO

Wiill

 

[grober]

1998 `or 1989 ?? different engines. straight 6 v V6 If its a V6 my money would be on the CRANK POSITION SENSOR.

 

[219]

These symptoms are not uncommon with the M103 engine ( and the 3.0 M104 ) - I have experienced them on two out of three examples I owned and have read the same complaint on this and other forums .

Firstly , the basics : the distributor caps on these engines have a notoriously short lifespan , as little as 30K - don't put anything other than Genuine MB or at least Bosch , cheaper alternatives do not last and are just rubbish in my experience .

Spark plugs - good quality plugs of the right temperature range are vital - I have found that a change of plugs cured the symptoms on more than one occasion , I ended up carrying spare set in the car .

Fuel pump relay - about the size of a 20 pack of cigarettes and usually with the word 'kickdown' printed on top - these relays have a printed circuit board inside and they develop 'dry joints' after 20 years in service - you can either buy a new one (expensive) or spend half an hour resoldering the board ( only cost being your time ) to fix .

If none of these sort it , come back to us .

 

[macseast]

Grober

you are good and sorry for the mistake it is indeed a 1989,well spotted.Does this effect you answer?

 

[grober]

If its a 1989 i.e. a straight 6 M103 then the advice offered by the posters above is sound. The crank position sensor is not usually a problem on these early engines. Other outside possibility is the EZL ignition unit is on its way out. I would try the distributor cap first. Sometimes if a car has been sitting a long time moisture gathers in the body of the distributor. When the car is started from cold everything is OK but as the engine warms the moisture vapourises and gets deposited on the inside of the distributor cap causing HT shorting. In addition to cleaning and inspecting the cap give the distributor body a good dry out with a hair drier when the cap is off.

 

[219]

The W124 models didn't get a V6 : the 300TE can only be a M103 .
After the M103 ended its run , the 300TE was replaced by the E280 and E320 , both developments of the M104 24 valve motor first used in the 300TE-24 , but with distributorless ignition and sequential injection - but still straight sixes , both of them .

The V6 engines didn't come in until the W210 , even then the earliest ones had straight sixes . IIRC , the V6's were first fitted to the W202 ?

 

[carat 3.6]

+1 Distributor cap and rotor arm.

 

[219]

I meant to add in my post above , having tried various spark plugs - Bosch , Beru , Champion , I found that NGK seem to work best and last longest .

 

[219]

Below is a picture of the engine bay of my 300TE , if yours looks the same then you have an M103 engine

Another variant of the same engine as fitted in a W201 190E 2.6

The 24 valve version ( M104 ) looks like this , engine bay of my 300TE-24

On both of the above , from memory , the fuel pump relay is behind the plastic cover behind the car battery .

The picture below shows the fuel pump relay in one of my W126's , the six cylinder relay looks very similar

 

[ray_hennig]

Well, yes and no ...

the distributor caps on these engines have a notoriously short lifespan , as little as 30K - don't put anything other than Genuine MB or at least Bosch , cheaper alternatives do not last and are just rubbish in my experience ..

Mine is an M104 motor but I think the rules are similar.

My experience suggests that caps can be cleaned up - mine was and it was 18 years old. I do agree that, for ultimate peace of mind, a new cap is the only answer. That's what I did despite the fact that the original, cleaned up cap appeared to be working fine.

The real swine for me was the rotor arm. The OP's symptoms of no hot start sounds like a rotor arm issue - it was for me.

I agree 100% - MB original only (I might be tempted by Bosch or Beru aftermarket). I had a cheap rotor arm fail with exactly those symptoms after 18 months.

RayH

PS: The fuel pump relay on the M104 is likely to be integrated into a thing called the Engine Subassembly Control (MotorAggregeteSteuerung or MAS). This box comes in a number of flavours depending on Aircon, 5-speed auto box etc.

 

[219]

Mine is an M104 motor but I think the rules are similar.

I had identical problems with both my 300TE and the 300TE-24 , however the 190E 2.6 was fine .

I have read numerous complaints such as the OP's from other owners with these engines .

 

[macseast]

Removed distributor tonight and it is in a very poor state as is the Rotor arm.About to order parts from eurocarparts and hopefully this should sort it,Fingers crossed?

 

[macseast]

Where is the best place to order parts from ? Eurocar parts?

 

[carat 3.6]

Order from mercedes if you can, or if you have to go with a pattern part make sure it is bosch.

 

[macseast]

Any good contacts for Mercedes "Genuine" parts?

 

[carat 3.6]

Any good contacts for Mercedes "Genuine" parts?

Not somthing I can help with there, allthough I do get a 10% discount for being a trade customer.

I had to buy one a few years ago from mercedes, and I think it was something like £140.

See what your local motor factors can come up with.

 

[MERC CLK 230 K]

New crank shaft sensor maybe

 

[219]

If you can get Bosch from Eurocarparts this will be fine as it is the original part .

I once got a BREMI cap and rotor arm from ECP as I did not specify a make and it did not last long at all .

 

[macseast]

Dear all

Brilliant!!!
Fitted a new distributor cap and rotor arm just over a week ago and so far no problems.

May get the fuel mixture checked as i think it is running a bit rich.

Thanks to all for there help