d jet assistance in London

Mercedes W114 280E



Do you know someone in the UK who can diagnose and fix my D jet issues in my car.

it fails to rev over about 3,500 revs, is there any help that you can give me. but hopefully a specialist in the UK you trust.

Hi Terry,

welcome here qith your M110 on W114. Unfortunately I do not know a workshop in London.

However, maybe I can help you. How do you reach the 3500/min? Slowly or rather quick and than the engine stops to accelerate like hitting a wall? Second case I had once.

like a wall, its also strange, and not consistent, the can run well for 300 miles and then like this for a long while with no apparent explanation

Hi Terry,

that sounds like a problem with a revolution limiter. There are 3 possible causes I have seen for that in the past:

1. Distribution finger. It has a delimiter with 6650/min. It is a centrifugal force delimiter. That could get stuck. You can either use a Bosch 1 234 332 177 finger without delimiter or reinstall a new 1 234 332 204 with 6650/min delimiter.
2. I saw a case where someone had a broken ECU that did not control the fuel pump any more. Then someone had installed a K-Jetronic fuel relais to handle the pump. That one also has a revolution delimiter and switches off the fuel pump when it reaches its rev limit. So if someone had installed a 4-cylinder K-Jetronic fuel pump relais on your car (by modifying fuel pump relais, that could also be a source of such a problem.
3. If your fuel pump cannot deliver enough fuel (because it is broken, hoses or filters are blocked), you would also see that effect but then at varying revolutions. It would not that much feel like hitting a wall like 1. and 2.

Have you measured fuel pressure in loop line?

In general we politely greet each other and sign with our names in this forum. Would be great if you could follow that.

Best regards, Volker

Hello Volker

Many thanks for your advice, I will ask my mechanic to have a try of the things that you suggest. I was looking at your chapters and chapter 8 appears to be only in german, please can you tell me if there is an English translation for this chapter as from the photographs. Many thanks again for your site, I have found it most helpful thus far.

King regards

Terry

Hi Terry,

I a, sorry, but I have not yet translated chapter 8 (fuel pump and pressure regulator) and chapter 14 (checklist troubleshooting). GIbe me some time, I will do.

Wishing you success with your troubleshooting! And be aware that my hints were given for a car that runs properly till 3600/min and then suddenly cannot increase speed.

Haven't been in London for a while now. My first time was when I was 14. I was so impressed of science museum! Have been to London often since then, but not in last 5 years. How is it to run a classic car in London? Do you also have to pay city fees?