[W124] It can't idle

[acordova at texas.net]

I'm pretty sure a bad fuel pump relay will cause hunting idle. For 
reference, Rusty sells those new for around $110 - $115 (www.buymbparts.com).

I haven't heard of anyone repairing a fuel pump relay. If it's bad, 
replacement is called for.

Alec Cordova
Taylor, Texas
89 300CE, 211K

Quoting Kristofer Johnson <refotsirk at telia.com>:

> Hi,
> Oxy sensor and fuel pump relay must be checked/changed.
> Your mech can easily test the function of the oxy sensor but the pump
> relay
> is harder.
> Try to borrow one and test, They are known to go bad.
> I changed my relay and the car got a smother fuel delivery and a more
> reliable idle.
> KJ
> 
> ----- Original Message ----- 
> From: "Sam Ho" <samhoming at yahoo.com>
> To: <w124list at mbcoupes.com>
> Sent: Monday, October 16, 2006 5:10 PM
> Subject: [W124] Re: W124list Digest, Vol 17, Issue 4
> 
> 
> Kristofer,
> 
> Thanks a lot for the suggestions.
> 
> Did chk the throttle & cables. Not a problem there.
> 
> Managed to try an 2 EZLs over the weekend. One from a breakers yard. P/No
> not compatible and car will not start at all.
> Then tried a compatible unit from a friend's car. Still more than one
> attempt needed to start. Then the idle problem still apparent
> after a short warm-up drive.
> 
> Question: What kicks in after the engine is warmed-up? That is the thing
> that is not working well. That's my deduction. The problem
> was there for  the last few months and it seems to be getting worse
> steadily.
> 
> My mechanic wants me to bring it in again to try the EGR relay and valve.
> Is
> that a good idea? May be will do that and try the Oxy
> sensor and fuel pump relay as well.
> 
> Cheers,
> Sam
>