[w_bulley]

I just bought a 1989 Mercedes 230e. First week it ran without problems, but now it just won't start anymore.

Fuel relay was playing up - vehicle would not start. Auto-electrician soldered loose connections on relay.
Engine started fine after that. Tried to start two days later - engine turned over, but would not fire up.

Car is now at European motor specialists in Cairns (Australia), but they have no clue regarding the cause of the problem.

They have done compression testing (150) on all cylinders, put a new fuel filter in (the old one was absolutely filthy), drained the fueltank and put 20 liters of Premium Unleaded in. Now the car gives plenty of spark and has plenty of fuel, up to where fuel is directed to injectors, but it still won't fire up.

They are saying that because it is an imported motor (from Hong Kong), it does not have a connection where they can hook up the computer for analysis.

Any help would be appreciated.

 

[lemmyb]

I had a similar problem to yours in my '87 230e. On mine, the ignition coil was the problem. The moment we repalced, the car ran perfectly. I ahve also been told that the fuel actuator can also cause similar problems when it has reached the end of it life.

I am not a mechanic and have very little experience in this area, but I hope what i written above gives you some clues.

Later
Dennis

 

[spanners]

Sounds to me like the fuel pump relay has gone bad again.

Quite often re-soldering is only a temporary fix.

Is ther any fuel pressure with the ignition switched on, or can you hear the fuel pump buz for 1-2 seconds every time you turn the ignition on?

 

[Yal]

Also you need an expensive set of diagnostic tools for a early W124 regardless of where it comes from. They probably only have OBDII tools thats why they can't figure out your analog car.

Like suggested above, check the fuel relay again and check the coil. Oh and I'd start looking for a second opinion to take my car too.

 

[w_bulley]

Thanks for all your replies folks,

A new coil has been tried and did not make any difference unfortunately.

Since we are getting fuel to the spark plugs, it must mean that the actuator is working.

Fuel pump relay has been rechecked by auto-electrician.

I forgot to mention before that a new fuel filter has been put into it.

Please keep coming with any new ideas you may have--much obliged.

 

[w_bulley]

the mechanics have said that there is no wiring harness soasto connect diagnostic machine to as it is an imported modile new coil and recheck off fuel relay have also been done still no luck.i am inclined to agree with you re 2nd opinion .

 

[NordStern]

Hi w-bulley.

This sounds fantastic. A shop not coping with a unwilling 230 should not call them selves specialists.

Your 230 probably has a 16-pole connector beside your battery. If they don't know that, they certainly won't know what to do with it. I can't imagine that MB would omit such a basic dignostic tool for any market.

It's easy to verify that a spark occurs. It's easy to check timing. Checking the fuel system can be time consuming, but not difficult. Sensors has to be checked, but you need a multi-meter, not an OBDII connector.

Make them verify that B+, ground and switched ignition are all available at fuel pump relay connector terminals 8, 11 and 9 (relay terminals 30, 31 and 15). Then bypass the relay by applying B+ to relay connector terminal 7 (relay terminal 87). If it runs then, check TD signal.

On this model, the "TD" signal comes from ECU terminal 25 and inputs to relay connector terminal 10 (relay terminal TD). The "TF" signal comes from ECU terminal 9 and inputs to relay connector terminal 2 (relay terminal TF). TD is an engine speed signal originating at the crankshaft speed sensor at the harmonic balancer, then processed to a square wave by the ECU. I use an oscilloscope, to monitor a good square wave on relay connector terminal 10 while cranking the engine. For the TF signal, monitor relay connector terminal 2 while cranking.

On your model, I think the fuel pump relay also controls the operation of the cold-start injector. Before the fuel pump relay can control the cold-start injector, it has to be told when to turn the injector on. The signal to do so is supplied to the TF terminal on your relay. TF is a temperature signal from the ECU, which tells the relay the engine is cold and needs an additional amount of fuel to get started. Unlike the square wave TD signal, TF is a simple on or off signal. To avoid flooding the engine, the ontime is quite short, and should occur only during cranking.


Now is the time for thinking. Does it have an alarm? What have we actually verified, and what way we have missed? Did they take a plug out and see the spark with their own eyes? Did they take out one or more injectors and verified the squirt? Ask them if they are familiar with closed loop systems. The simplest test is to ask them to tell you what CIS-E stands for. If they don't know even that, get your car out.

It's standard Bosch, and came in a lot of Audi's, BMW's, Porsche's, VW's, and others. So it should ring a bell.

Sometimes the simplest things can confuse an otherwise smart guy. Once I met a guy who didn't have dimmed lights. Everything else was perfect. Even the N/7 light bulb controller was satisfied, as it always is if two circuits compare even Ohm values. He had been "everywhere". And "nobody" could fix it. So I was stupid enough to swap a bulb. Voila! Swapped the other bulb, and the man had lights.

I too have been rumbling for hours and days, just to find the simplest mistake.

Good luck to ya mate.

Regards

Geir

 

[w_bulley]

Geir -- thanks heaps for taking the time to explain all that to me. I'm keen to get this car rolling, so I'll be sure to check it out.

Will get back to you all.

Thanks,

Bill

 

[benzzie]

Just my expirence try to get a new CDI ,hope it works i had the same probs also last time and i have been changing the same thing as you ,but turns out to be the CDI damn...

 

[w_bulley]

Geir.
have been to the workshop to check dignostic connector
on my 124/1989 m/b.This car has an 8 pole connector
off which 1 and 7 are operational .1 being earth and 7 being air conditioner.Relevant tests were unable to be done .A new coil and plugs have been tried .Spark exactly the same as old plugs and coil (good).
fuel is at all injectors pressure is also right.
Compression is 150 on all cylinders,timing is also correct.
He beleives or is hopeful that there is a fault in the ignition relay His last resort is to try a new relay .
If this does not work i will take the car to a auto electrician and go from there .
Thanks again every body will keep you posted .
Bill.

 

[NordStern]

Hi w-bulley.

If you have an 8 pole connector, I would check the VIN to verify that it's really an 89 model. After the A, the digits should be around 700 000 and upwards. They stopped producing the 8 pole connector in september 87, I think. But definitely before 1988. If you have a sunroof, check that the switch button is lighted. If it's not lighted, it's a pre 1988 model. Not that it matters so much in the quest for what's wrong with your engine, but still worth looking into.

One very quick and dirty way to see if the relay signals might be the culprits, would be to pull the car with another car over some distance. If it after a while suddenly comes to life, and runs fine untill it's stopped, but fails to start again when cold, you'll have an important indication to work with. As I said, it's not Einstein at work, but I have tried it with success at the roadside.

Regards

Geir

 

[w_bulley]

Geir .car is an auto matic an will not start by towing aero start has been spraid into carby whilst cranking still no luck ......bill

 

[w_bulley]

Hi Geir .
Some luck at last .I spoke to a wreckers in Brisbane this afternoon and he suggested i try the Thermal-Over ride.fuse was ok so i then pulled it apart and put it back together again Lo and behold it worked .Moisture
appears to have been the problem.
I would like to thank every body for all there help
A really big thanks to you all


Bill

 

[suroor]

Thanx you guys, I have the same problem with my w124 230e. Was a little toubled but with all this info I at least have a direction