W124 E220 surging at idle

[CRJ]

I have an occasional surging problem with my E220 Cabriolet (W124).
It doesn't happen consistently but can be quite alarming.
It occurs in the following circumstances :-

a) When the car is warmed up and idling in traffic in "D".
b) After engaging "R", again when the car is warmed up

In both cases idling momentarily increases to about 1200-1500 rpm

The HFM air sensor has been replaced

Does anyone have any idea what could be causing this ?

 

[Bolide]

The throttle body usually seems to be the culprit with E220s. I'd give it a good clean and see what happens

Nick Froome
www.w124.co.uk

 

[kth286]

Chris

First thing is to get the diagnostic codes read by someone experienced with your generation car.

Depending if codes stored, and what they are, will guide you for the next actions.

If you are anywhere near me in Berkshire I can do it for you.

E-mail me on kth286@aol.com

if interested.

 

[thebeard]

Hi all

I'm having this surging problem on my e220 saloon 1994 car w124.

I've cleaned the throttle body with carb cleaner not sure if I did it correctly as it hasn't beem cured.

Anyone know if my car has a purge valve what it looks like and where it might be?
I've been told it could be this.

 

[kth286]

it's on the inner wing under the bonnet (NS wing).

it is the small black unit that has the word MOT on top of it.

after the engine has been running for some time and up to temp, it should pulse strongly about every half second or so.

you can both feel it and often can hear it ticking loudly each pulse.

If it is not pulsing it may be stuck in open position and allowing fuel tank fumes to be drawn into engine at wrong moments thus causing the surges.

They cost around £100 new from merc.

 

[thebeard]

purge valve e220 1994

Any idea on how to test these ??

 

[television]

Take a read here

andhere

 

[thebeard]

Changed the Purge valve but still get the surging so it wasn't that :-(

 

[kth286]

Changed the Purge valve but still get the surging so it wasn't that :-(

Why did you change it ?

Have you had the fault codes read ?

 

[television]

Surging at idle is often a vacuum leak where the vacuum is at the highest point,,this could be any component on the inlet chain that could leak, including the inlet manifold, only the introduction of air can speed the engine up, when it speeds up the vacuum falls off, and so the cycle starts again, over fueling will not speed the engine up,it needs the air

 

[jibcl500]

Another thing to check on these engines is the inlet manifold bolts, mine where no more than finger tight on some and after tightening them up the car ran much better, may not be the problem but worth checking.

jib

 

[television]

Another thing to check on these engines is the inlet manifold bolts, mine where no more than finger tight on some and after tightening them up the car ran much better, may not be the problem but worth checking.

jib

Absolutely Jiles, Funny years ago we would go round tightening all bolts years ago,,we do not do it any longer

 

[jibcl500]

Absolutely Jiles, Funny years ago we would go round tightening all bolts years ago,,we do not do it any longer

I used to buy the classic range rovers, I bought some 80 RR's in a space of 2 years and the amount of cars that came to me because the owner though the tappets needed replacing was huge and all it was was the exhaust manifold bolts needed tightening.

jib

 

[thebeard]

Why did you change it ?

Have you had the fault codes read ?

I changed it because I'd read elsewhere that it had been a problem only cost me £10 at a breakers and very easy to fit so worth a try.

I haven’t had the fault codes read.
I have been looking at making a fault reader and giving it a go myself.

I'll go to maplin tomorrow and make one I think.

 

[thebeard]

Does anyone have a link to fault codes for w124 E220 / 220E Engine type 111.960 ?

 

[television]

You will find them here

But do not go to the home page

 

[thebeard]

You will find them here

But do not go to the home page

Thanks but my model is not covered there.

I've got a 1994 w124 e220

 

[television]

Thanks but my model is not covered there.

I've got a 1994 w124 e220

I do have the auto data fault code list when I turn that machine on I will check

 

[kth286]

Thanks but my model is not covered there.

I've got a 1994 w124 e220

the fault codes are the same but obviously 4 cylinder instead of 6.

 

[chodder]

w124 e220 surging on idle

hi the guy with the surging problem post your email and i will put you right, i had the same problem on mine but no one on here would help!!!