Mercedes-Benz E-Class W123 - Mercedes W123 Pierburg 175CD Carburettor

Honest John Back Room » Technical matters
What is life like with your car? Let us know and win £500 in John Lewis vouchers | No thanks
View Threaded
Fri 11 Feb 2011 15:44
Mercedes-Benz E-Class W123 - Mercedes W123 Pierburg 175CD Carburettor - ngshinong

Good day. I have a 1985 W123 running on M102 2.0 engine on Pierburg 175CD carburettor with a red damper cover. I notice that my car is severely underpower and heavy on fuel (less than 18MPG average). Also, when i accelerate in full, there will be a lot of black smake coming out from the exhaust. Ive adjusted the air/fuel mixture on the warm water autochoke but is still the same. My car start very well (1 kick start) whether on a hot or cold day and idle very well. What can be the problem? thanks.

Reply | Report as offensive | Link
Sun 13 Feb 2011 19:42
Mercedes-Benz E-Class W123 - Mercedes W123 Pierburg 175CD Carburettor - tdc

Sounds like you still have an autochoke problem.Any way of running with it removed to see how car performs?

Reply | Report as offensive | Link
Mon 14 Feb 2011 17:17
Mercedes-Benz E-Class W123 - Mercedes W123 Pierburg 175CD Carburettor - ngshinong

not sure about that but the autochoke is running with water coming from the radiator. If I removed it I don't know how to seal the pipe.

Reply | Report as offensive | Link
Mon 14 Feb 2011 17:29
Mercedes-Benz E-Class W123 - Mercedes W123 Pierburg 175CD Carburettor - elekie&a/c doctor
I seem to recall these have an adjustable jet at the base of the carb to adjust the mixture.Is there a large solenoid device with a lock nut at the base of carb?Release nut and screw solenoid in or out to adjust mixture.hth
Reply | Report as offensive | Link
Mon 14 Feb 2011 17:38
Mercedes-Benz E-Class W123 - Mercedes W123 Pierburg 175CD Carburettor - ngshinong

yes, I did adjust the solenoid and disaster, my car is jerking under acceleration and total lost of power. And the idle speed seems to be inconsistant. sometimes It goes up to 1500rpm and I have to keep on adjusting the vacuum governor to bring the idle down.

Reply | Report as offensive | Link
Mon 14 Feb 2011 18:55
Mercedes-Benz E-Class W123 - Mercedes W123 Pierburg 175CD Carburettor - SteveLee

Worn needle and jet I suspect - assuming the diaphram is okay - change the lot, quick and easy to do - doesn't cost much either.

Reply | Report as offensive | Link

A guide to how much VED you will need to pay on your car.

Road Tax Bands and Rates