[Ravindra M]

Originally Posted by laxmanrk

Hi all

This did it. The vehicle finally starts and stays at idle. But vehicle does not stop if you turn the key off. The vacuum pipe needs to be re-connected to turn it off.

There is an engine-shut off actuator integrated in the pump. When vacuum is applied, it pulls the lever which in turn cuts the fuel supply and engine stops.

There could be either of 2 issues
(a) there is continuous vacuum at the valve, which explains why the engine did not start at all. You can do a simple experiment - while the engine running and the ignition key at the usual ON position connect the vacuum line and if it dies, then you have the problem here. You need to investigate the vacuum distributor at the key. I am not familiar how it is connected at the key.
(b) Less probability : the vacuum actuator could also be a problem - part number 0928400271. Google it and you will find it.

[Viraat13]

Originally Posted by laxmanrk

Viraat, Is your E250D a W124 or W210? Please PM me your VIN number. I will get you the part number and probably links of where you maybe able to order it on the internet.

It's a W124 (need to edit my signature!). I'm taking the car to Patel Auto (Authorised MB) tomorrow for a full transmission check up. I think the expense is worth the peace of mind. The modulator is available outside for around 2800 and Patel Auto is saying it'll cost me 3500, provided it needs to be changed. And the cost of the check up is 3500 too.

Thanks for the offer and I will take you up on that post Monday if need be.

[911varun]

Originally Posted by laxmanrk

Hi all

Finally, after much fanfare and loads of trials and errors, we disconnected the vacuum stop line from the key to the FIP.

This did it. The vehicle finally starts and stays at idle. But vehicle does not stop if you turn the key off. The vacuum pipe needs to be re-connected to turn it off.

Now, I need to figure out the vacuum diagrams and check that. Vacuum pump seems to be in good order.

Any other inputs appreciated.

Viraat, Is your E250D a W124 or W210? Please PM me your VIN number. I will get you the part number and probably links of where you maybe able to order it on the internet.

here you go, yours should be 606.910, same as mine :-)

It should be a vacuum problem, check the vacuum switch-over valve mounted in the intake manifold.......

Originally Posted by laxmanrk

Hi all

Finally, after much fanfare and loads of trials and errors, we disconnected the vacuum stop line from the key to the FIP.

This did it. The vehicle finally starts and stays at idle. But vehicle does not stop if you turn the key off. The vacuum pipe needs to be re-connected to turn it off.

Now, I need to figure out the vacuum diagrams and check that. Vacuum pump seems to be in good order.

Any other inputs appreciated.

Viraat, Is your E250D a W124 or W210? Please PM me your VIN number. I will get you the part number and probably links of where you maybe able to order it on the internet.

Originally Posted by Viraat13

Curious to know what white smoke on cranking means. Could you please explain further?

Also, can anyone help me source a automatic transmission modulator for the E250D Automatic? I need the one for the first and second gears. It's a red coloured modulator. Even the part number would help.
Thanks.

Hi Viraat,

Check peachparts, you should be able to find it here, I find them the most comprehensive on 124's parts, but I am yet to order from them...

[laxmanrk]

Guys

Finally, checked the entire vacuum piping and it turns out there was some cross connection.

All sorted now, refitted many things and voila vehicle starts on first crank.

Now, following are issues that need sorting.

1) idling is a bit rough, mechanic says there is still some air in the system. Contemplating the addition of an electric fuel pump. comments welcome.

2) Tachometer is not working at all. Need inputs.

Will try and post pictures when possible.

Thanks guys for all your support and inputs

[Viraat13]

Originally Posted by 911varun

Hi Viraat,

Check peachparts, you should be able to find it here, I find them the most comprehensive on 124's parts, but I am yet to order from them...

I didn't get around to getting the transmission checked cause today one of the fuel likes cracked and the car sucked up air and stalled. I spent 6 hours at the mechanics, but it was already dark and the progress was slow. All the rubber fuel lines under the hood have been changed, and tomorrow the filter inside the tank and the rubber components there will be changed.

This sucking in of air business is a real pain and a bit of a mystery.

[laxmanrk]

Hi guys

Finally glad the car came home today!

The Tacho had faulty wiring again!

Two issues

engine temp sensor isnt going up beyond 40 degrees but thats actually impossible so need inputs on what could be wrong!

Secondly, the engine idle is quite noisy! But after 1200 rpms its extremely smooth all the way to 4500! any tweaks to smoothen the idle?

Thanks for all your support!

Viraat - There are loads of guys on the internet who have installed an additional electric fuel pump to ensure the air get removed quickly!

[911varun]

Originally Posted by laxmanrk

Hi guys

Finally glad the car came home today!

The Tacho had faulty wiring again!

Two issues

engine temp sensor isnt going up beyond 40 degrees but thats actually impossible so need inputs on what could be wrong!

Secondly, the engine idle is quite noisy! But after 1200 rpms its extremely smooth all the way to 4500! any tweaks to smoothen the idle?

Thanks for all your support!

Viraat - There are loads of guys on the internet who have installed an additional electric fuel pump to ensure the air get removed quickly!

1. Change Engine Temprature Sensor, the one at the rear of the engine
2. There is a Tacho Sensor beneath the dashboard, can be accessed from above the accelerator paddle. Check the connections of this sensor.
3. The rough idling could be due to stretch in the timing chain, tell your mechanic to stretch the pump away from the engine block and check the idle sound without the engine belt on. It could be the belt tensioner or the shocker also making accessive noise at idle.
let me know if it works :-)

[laxmanrk]

Thanks for the reply Varun!

The tacho issue is now sorted.

Now, if you see previous posts, my engine has a new timing chain, inlet camshaft and 2 inlet valves. So i suspect any chain stretch.

But my mechanic says the noisy idle is because the injectors and FIP have been re-calibrated. A bit of carbon build up should smooth things out! But I am not sold on this concept. I think there is some idle/ timing tweak on the FIP which will smoothen this.

Now for the engine temperature, could you post a picture of the location of the sensor?

Also is there some way I can figure out, the failure of this sensor? Whether the engine will still perform in the actual required temperature range or if this sensor is required for the additional fan to turn on?

[Viraat13]

Originally Posted by laxmanrk

But my mechanic says the noisy idle is because the injectors and FIP have been re-calibrated. A bit of carbon build up should smooth things out! But I am not sold on this concept. I think there is some idle/ timing tweak on the FIP which will smoothen this.

Did you refurbish the diesel pump or change the rubber seals? If so, that explains the rough idle and the excessive clatter on idle. Your mechanic is right, it'll settle down in a while.

[Viraat13]

Originally Posted by vikramvicky1984

Call Mahesh Bhai at Maganlal stores in Opera house ( +91 22 23826081/ 30016244), he has most w124 stuff in stock.

Thanks for this contact! I need an automatic transmission modulator for my W124 E250D and it isn't available anywhere in Delhi. Even the authorized Benz workshop (Patel Auto) doesn't have it. He has it in stock, so I will try and get it from Bombay somehow.

[vikramvicky1984]

Originally Posted by Viraat13

Thanks for this contact! I need an automatic transmission modulator for my W124 E250D and it isn't available anywhere in Delhi. Even the authorized Benz workshop (Patel Auto) doesn't have it. He has it in stock, so I will try and get it from Bombay somehow.

He'll send it via courier and you can pay him by bank transfer. I have transferred money online to him once. I don't think it'll be a problem

[Viraat13]

Originally Posted by vikramvicky1984

He'll send it via courier and you can pay him by bank transfer. I have transferred money online to him once. I don't think it'll be a problem

I'll try and get a friend of mine to get it. He travels between Bombay and Delhi often enough. I'll only do the bank transfer as a last resort. Thanks.

[911varun]

Originally Posted by laxmanrk

Thanks for the reply Varun!

The tacho issue is now sorted.

Now, if you see previous posts, my engine has a new timing chain, inlet camshaft and 2 inlet valves. So i suspect any chain stretch.

But my mechanic says the noisy idle is because the injectors and FIP have been re-calibrated. A bit of carbon build up should smooth things out! But I am not sold on this concept. I think there is some idle/ timing tweak on the FIP which will smoothen this.

Now for the engine temperature, could you post a picture of the location of the sensor?

Also is there some way I can figure out, the failure of this sensor? Whether the engine will still perform in the actual required temperature range or if this sensor is required for the additional fan to turn on?

1. For carbon build-up, I would recommend you to put 1 litre servo pride engine oil in a full tank of diesel only once and see the noise disappear :-)

2. The sensor at the read of the cylinder head is the engine temp sensor and the one in the front beside the fuel filter is the AC temp sensor. the front one will control the actuation of the additional fan.

hope this clears the air

[Viraat13]

Originally Posted by 911varun

1. For carbon build-up, I would recommend you to put 1 litre servo pride engine oil in a full tank of diesel only once and see the noise disappear :-)

I believe even a diesel injector cleaner will do the trick. I added a bottle of that in my last tankful and the engine et al is much smoother now. I used the one made by ABRO.

[laxmanrk]

Have been using the car for the last 2~3 days and the temperature gauge in the instrument cluster is still not showing the right temperature. It just rises to 40~50 degrees and it stays there.

Now, had the A/C system charged today with gas and the A/C is nowhere near as efficient as it was before.

A/C guy says there is no leak whatsoever as he did the vacuum test and it passed.

Also the additional fan in front of the radiator used to turn on when the A/C was switched on, now it doesnt.

But during the testing we removed the temp sensor near the fuel filter and
the additional fan came on and just stayed on at full speed. once we put the sensor back the fan stopped.

I am also suspecting the duo valve which circulates hot water into the heater circuit.

Firstly I need the A/C electrical and vacuum diagram if any one has it.

Thanks all for your inputs and support - especially Varun and Viraat.