I expect to receive my rebuilt/resealed P/S tandem pump from ZF Industries NLT 1700 hrs PST FRI 30MAY03.

I will update this thread ASAP, thereafter.

I have just replaced my original (LUK) power steering + tandem pump with a new (ZF) one.

My stalling problem still exists.

: (

My quest for a solution continues...


http://www.500ecstasy.com/forums/showthread.php?s=&threadid=53

for ****s-n-giggles why not replace the crank position sensor?

yes, that will be next...

Scott,

I just finished reading this thread. Having dealt with a similar type of problem on another German car, I can appreciate your frustration.

Question: have you removed the screen that covers the MAF sensor?

I ask because a friend with a '94 E500 has also lived this thread. He's the type that wants to wring out the last 1/10th HP, so in an effort to increase airflow, he removed the screen over the MAF. Shortly afterwards, the stalling problem appeared. Many, many months, $$$, and parts later, a smart tech finally determined that turbulent air flow over the MAF was enough to throw off the readings returned by the sensor and hence confuse the LH brain. The screen is there to straighten (normalize) air flow over the hot wire.

If you've pulled the screen, try replacing it.

Hope this helps.

Jim

__________________
--
Jim Stadter
'94 E500 Black Pearl
'89 190E 2.6 Black Pearl
'88 928S4 5-speed
Austin, TX

Thank you very much for your contribution; however, my MAS is less than 6 months old and has never been modified in any way.

Your/your friend's tech's hypothesis is congruent to the "large(r) volume airbox culprit" theory; however, that has been ruled out, scientifically, in my particular case.

The hunt continues!

Scott,

I don't know if you have the stock airbox or have modded it but
Jim's point is about the domed screen inside the airbox above the MAF, not the screen on the MAF itself. Apparently the screen inside the airbox is designed for proper airflow over the MAF and removing it will cause idle/stalling problems. It has nothing to do with the airbox itself, just the domed screen inside it. Just another thought!

Randy
'94 E500

Thank you; however, my domed screen is/always has been present.

Further up in this (exceedingly lengthy) thread, you will note that using my OEM airbox made no improvement to my stalling problem.

Just checking - didn't have time read through the entire thread!

The person who told me about this had the local dealer charge him $400+ to try and find the problem. He asked them to try a stock airbox and they said they did as part of their work. Well, 1 year and much more $$ later he put on a stock airbox and that was it. Looks like the dealer cost him a lot more than $400!!

Randy

Bump.

STILL no solution? This is insanity....!! Side note - how old are the engine & tranny mounts? I wonder if they could be allowing the engine to move around during "U-turn" manuevers, and make something unhappy? I'm really running out of ideas. Wow...

__________________
Check out my website photos, documents, and movies!

My engine and transmission mounts are less than 2 years old (I replaced them in July 2002).

*sigh*

Perhaps the car is possessed. Might be time for an exorcism. Know any good priests?

Seriously though, this has gotta be depressing to replace so many parts and STILL have the same problem! It would drive me insane were it my car.

1) 6.0L or 6.5L M119 displacement upgrade

2) NOS

3) 1 & 2

Heh-heh. Yeah, 6.0L and/or NOS would be definitely sweet. However it would be a real bummer if the problem persisted with the 6.0L swap. I think they re-use most of the engine controls, and only mess with the bottom end. Pretty likely to still have the same issue!


Anyway - could you provide a little more data:

1) Does it happen EVERY time you pull a U-turn?

2) Does it have to be a U-turn, or any sharp low-speed (no throttle) turn, like pulling into a parking lot or side street abruptly?

3) It *never* happens in a straight line, right?

4) Did you ever reconcile the difference between the hand-held tach and the dash tach? I'm curious what the actual idle speed is... sub-500, or 600+.

5) Has any thought gone into the possibility of it being related to fuel delivery (liquid), instead of an electrical problem?

6) Last brainstorm - can you get a dealer techie type to hook up a diagnostic laptop to the car and then drive the car while connected? Then see if anything turns up when you go pull some U'ies and make it stall? There has to be *some* clue we're missing here...!

FWIW,

When I was in the Bay area and had dinner with run.exe and Shanta, Shanta picked me up at my hotel and drove me to the restaurant in her E500, and she explained to me that her E500 exhibited the same low speed stalling when making a U-turn.

She told me she had learned that she needed to give the engine a little bit of throttle when making a u-turn to prevent the stalling. It made for a very fast U-turn, but it worked.

The strange the is that the car would just shut off.

It wouldn't shake and stumble like one would expect, like when an engine struggles to idle when the idle / air mixture is set too lean.

Maybe it has to do something with The Bay area....

__________________
Paul S.

2001 E430, Bourdeaux Red, Oyster interior.
79,200 miles.

1973 280SE 4.5, 170,000 miles. 568 Signal Red, Black MB Tex. "The Red Baron".