W124-88 Pieburger probleme start

[novisen07]

Hi, start by apologizing for my English. Hope you understand.
I have a w124 1988 gasoline with pieburger carburetor which a while ago started to fuss. i have changed spark plugs, cables, distributor cap, rotor, ovp relay temp sensor but nothing helps. It sometimes starts cold and goes perfectly. When it is warm it can run without any problems. When it goes it goes smoothly and without any problems. When it does not want to start at once, I have to wear it for a while. Starts but has a very weak and flabby run for one minute, then it gets speed and can go well for a long time. It is my problem that I do not know where to continue in the search. Haven't found any vacuum leaks. Have used starting gas in the search to find any leaks.
Hope someone can give my tip.
Please
Soon it goes to the scrap metal

 

[novisen07]

No one??

 

[WOODYTHEWISE]

Its unusual not to receive a reply of some sort. Hopefully we may prompt a reply from someone who may be able to help.

 

[Bellow]

Interrogate the spark plugs when it wont start.
Wet with fuel - too rich = cold start enrichment problem (or no spark - check also)
Dry of fuel - no fuel = check carburettor for faults, blockages, float height.
Dry but with smell of fuel = cold start enrichment problem.

The spark plugs are a window into the combustion chamber. Use them to 'see' what is happening inside the engine.
Come back here with more information and we'll help from there.

 

[grober]

Many possibilities here these cars were fitted with either a Zenith- Stromberg Variable choke sidedraft carburettor with an automatic shut off valve and automatic choke or the equivalent 175 CD Pierburg. They have a mechanical fuel pump [ diaphragm type] push rod driven off an auxilliary engine shaft. Fuel is pumped from the rear tank to the carb. First thing I would try on older cars with intermittant faults would be fuel delivery. There's an exit strainer/filter at the tank fuel outlet- sometimes these get choked intermittantly by debris/rust thats acccumulated at the base of the tank OVER THE YEARS leading to poor fuel supply. Poor running when cold could be down to a faulty automatic choke mechanism.
Try searching for Pierburg 175 CD on this forum and online for more info.
hows yourGerman?
Einstell-Anweisung 175CDT M102, 01.1981

 

[clk208]

Thread diversion. Never knew there was a carburetted W124.

Family had a D reg 1987 W124 230E from 1 year old back in the day. Guessing the E meant it was injection though.

Had a 1985 Ovlov 200 series at the same time (still got) which has a Pierburg 175CD. Might be useful to know these were also in other cars if you’re looking for parts. Never had any starting problems with the pierburg carb but have had spells of rough running cured by a new diaphragm, needle and jet every few years.

 

[novisen07]

Thank for info. The carburettor is a Pierburg 2E-E. I have tried all tips, no result. Now I got a tips to replace a new sensor. I have order so I´m waiting. The probleme is the fuel. When the car start after some warm it goes perfect and start good. I have had the carburetor cleaned and cleaned, found no dirt, so now I wait for the sensor so obviously should have an impact over the cold start.
I've changed: spark plugs, cables, distributor cap, rotor, ovp relay, fuel pump, three sensors, rubber bellows under carburetor, vacuum hoses, control box.

 

[grober]

OOPS WRONG CARB
TRY THIS FOR DETAIL ON THE 2E-E MERCEDES VERSION
https://www.ruddies-berlin.de/index2.html I have tried to link directly to the relevent pages/diagrams but can't seem to post links. The info you want is probably on that site somewhere e.g. here's a fault finding list I copied and pasted


Maintenance Carburettor 2E-E AUDI / VW / Mercedes-Benz / OPEL
Complaint : Possible Reason : Remedy :

Engine does not start in cold condition. Temperature sensor/primary throttle acuator defective. Replace temperature sensor/primary throttle acuator (F1).

Engine stops after cold start driveability. Heater honeycomb failed (Mercedes-Benz only). Replace heater honeycomb (presrntly no Pierburg part).

No/poor idling after cold start (2 to 3 min). Rubber flange distorted on lower side (not detectable by spraying). Install rubber flange 3.50001.33 VW (R1/R2/R3) Mercedes-Benz = 3.50001.31 / Opel = 3.50001.32

Poor driveability with cold engine. Intake manifold preheater (hedgehog) failed (check temperature according to check list). Replace intake manifold preheater (2) 4.07316.02

Poor driveability particulary with cold engine. Armature of primary throttle actuator turned. Check primary throttle actuator with ring gauge."Caution:do not apply battery voltage", and replace, if necessary. 4.07360.07 + Ti206

Poor transition during acceleration. Throttle valve potentiometer/ primary throttle actuator defective. Replace throttle valve potentiometer (B1/B2) /primary throttle actuator (F1). Ti191

Idle speed not constant (control failed). Throttler valve actuator/throttle valve potentiometer devective. Replace and adjust throttle valve actuator (C1/C2) /throttle valve potentiometer (B1/B2)

Temporarily no iding with engine at operating temperature. Charcoal valve stays temporarily open. Check by disconnecting hose, replace valve, if necessary.

Engine speed remains temporarily high (approx,3000/min) when slowly reducing accelerator position. Check throttle valve actuator potentiometer as described in Ti194 . If resistance valve jumps, replace throttle valve actuator.

Temporarily or continuously elevated idle speed. Plug connector of throttle valve actuator loose (occurs ofter, since cable is short and throttle valve actuator difficult accessible) . Check throttle valve actuator, replace, when high resistance is indicated and fasten plug connector securely.

Engine idles erratically. Mixture control screw (RG)misadjusted or lambda sensor defective. Check CO adjestment (flash code), check lambda sensor and replace, if necessary.

Rough idling, part load jerking, idle speed not adjustable. Rubber flange leaking. Replace rubber flange (R1/R2/R3) , check idle setting.

Motor stops during deceleration after wide open throttle driving. Main jet cut-off defective, Replace main jet cut-off. Set 4.07304.02 adjustment to 1,5mm between jet support and plate.

Poor starting in hot condition. Float chamber switch valve defective, engine overflow. Replace float chamber switch valve (K1).

Poor driveability with hot engine. Vapour bubble formation and foaming of float chamber. Install pressure regulator 7.21517.02 between vapour separator and carburettor.

 

[novisen07]

Thanks. I have the manual and try to follow but germany is not easy.
Thanks for now. I must do some job.

 

[grober]

Understood-- sometimes its best with mystery symptoms / poor performance on these old carbs its best replace with a simpler manual choke substitute thats more reliable such as weber /dellorto this company may be able to help.
Leading Weber carburettor distributor in the UK

 

[novisen07]

Understood-- sometimes its best with mystery symptoms / poor performance on these old carbs its best replace with a simpler manual choke substitute thats more reliable such as weber /dellorto this company may be able to help.
Leading Weber carburettor distributor in the UK

Thanks for tips. I will contact.

 

[grober]

HERE'S THE RUDDIES LINK
Service Anweisung 2E-E DB 190+200
I did not appreciate that these ECOTRONIC carbs are partially electronically controlled via a mini ECU and Lambda sensor input!

 

[novisen07]

HERE'S THE RUDDIES LINK
Service Anweisung 2E-E DB 190+200
I did not appreciate that these ECOTRONIC carbs are partially electronically controlled via a mini ECU and Lambda sensor input!

A very bad carburetor and there is no living mechanic left who has experience with its mode of operation. It's like when tv, n came in the 50's. The repairmen changed one tube after another until they got the appliance running. This is the case with this carburetor. It's just to replace the different parts one by one. Of course it costs a lot of money but the car is good so I try for a while. Waiting for a new sensor that affects the cold start,

 

[novisen07]

No carburettor to change with.

SouthernCarburettersLtd <[email protected]>
16:33 (för 37 minuter sedan)

Eilert

Sorry there is no replacement carburetter for that that we know off.

Regards
Roy McNeill

 

[grober]

THATS A PITY I had hoped a twin choke weber might have fitted.

 

[grober]

A LIITLE MORE ADJUSTMENT DATA
http://mbklassiekerclub.nl/images/fbfiles/w123/images/mercedes_carbs.pdf

 

[grober]

and a description of function/operation principles here[ in english] this is good info !!!!
https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=11&ved=2ahUKEwip3aLiyM7kAhWvThUIHZA1AOsQFjAKegQIABAC&url=http://www.w201club.com/forum/index.php?act=attach&type=post&id=56&usg=AOvVaw1qg7CQhgSdPy60ZVgxhw2J

 

[novisen07]

Hi again. Thanks for your helpful support. I will look carfully.
I replaced the sensor but no help. But now I think I´m on the road to find the probleme. There is no volt at the element under the carb. I have looked for a wiring schema from the ignition switch to the relay under the fusebox. There is a relay 005420219 to supply power to the element under the carburetor. But there is no current to the relay. i can not find a wiring schema.The one I find is very bad, can´t read them.

 

[grober]

A quick look in a similar age 190 activated relay would show the relay coil is activated via fuse 2 [8 amp]- might be a different fuse on the w124 ---in the fuse box on ignition switch on. the main power feed into the relay would be permanent [ from a possibly unfused 12v supply direct from the battery] BUT the relay coil is earthed via a thermal switch [ 40 degree F ] somewhere on the engine block to complete its circuit I imagine the w124 arrangement is similar
The problem with most online wiring diagrams is they are USA sourced and I don't think they ever got carburettor cars or these preheaters or " hedgehogs "as they were nicknamed.

 

[novisen07]

Once again, thanks.
The ground cable from the relay goes in the cable harness at the left inner shield to a bolt that connects 4 other ground cables and is screwed into the shield.
There is no power to the relay point 30 which will give power to point 76 which will give power to the element. That is the problem I do not find where the cable is located that should provide power
to the relay.
It might settle for the week when I get help from a car electrician. Until then I have to wait, I don't have the knowledge.
Have a nice weekend.