I'm guessing that whatever was causing your no start problem is causing this problem. Even though your no start problem was resolved it wasn't ever really clear as to what was causing it correct? Have you tried running it off a separte bottle of fuel with this current problem?

__________________
1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13

I think it was just air stuck in the lines that was causing the no start problem. Going back to that issue, it was running fine before I tore into the fuel supply system, but I had the hardest time getting all the air out after I put everything back together. Now it starts instantly even in cold weather and idles nicely.

Today I installed 2 new valves on top of the valve cover...I don't know exactly what they are called, but they are the white valves that distribute vacuum to the EGR valve, etc. I also blocked off the EGR valve. The car actually seemed to have more power than before but still very weak. It revved way past its shift points and then the shifts were very rough.

I also checked the timing marks on the crank and cam and they line up perfectly at TDC. There doesn't seem to be any slack in the timing chain. Again, I don't know the history of the timing chain so I probably will change it at some point, but there is nothing obviously wrong with it right now.

I'm skeptical about that. Didn't you try it on an alternate supply back then? I still think the problems are related. Too similar to be coincidental. Both are likely inadequate fuel supply.

__________________
1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13

A lot of air getting into the system? Usually if something goes wrong I pay attention to the last area worked on if it was not long ago.

No sense d***king around if you think it's air. Install a temporary clear PVC line in place of return to tank (aka cigar hose) line. You will see air if that is your problem.

__________________
85 300D turbo pristine w 157k when purchased 161K now
83 300 D turbo 297K runs great. SOLD!
83 240D 4 spd manual- parted out then junked

Agreed. The lift pump, especially if just rebuilt, can *suck a golf ball thru a garden hose*.

The low pressure fuel supply system operates at below atmospheric pressure due to the intense suction from the lift pump. If there is a pin hole leak it will suck air.

__________________
The OM 642/722.9 powered family
Still going strong
2014 ML350 Bluetec (wife's DD)
2013 E350 Bluetec (my DD)

both my kids cars went to junkyard in 2023
2008 ML320 CDI (Older son’s DD) fatal transmission failure, water soaked/fried rear SAM, numerous other issues, just too far gone to save (165k miles)
2008 E320 Bluetec (Younger son's DD) injector failed open and diluted oil with diesel, spun main bearings (240k miles)

1998 E300DT sold to TimFreeh
1987 300TD sold to vstech

This is a great idea. I know you suggested it back when I had other issues and it did help then, but I'd since removed it. I will reinstall and see what I get.

On my w124, there are 3 filters. The pre-filter, the filter, and the tank strainer. A lot of people forget about the tank strainer but it gets clogged with fungus and when you need more fuel, you can't get it.

Check to see what your model has in the fuel tank.

I checked the tank strainer when I drained all the fuel and replaced with fresh, there was a little bit of crud but not a lot. I was actually hoping this was my fuel delivery issue since it is a relatively easy fix.

There is a pic of a tank strainer in post 142 of Jerhofer's excellent post about his new 1973 280SEL.

Take the shutdown hose off of the IP, and see what happens. You could have a misrouted vacuum line and as soon as the shutdown sees enough vacuum it, it does what it does.

__________________
CC: NSA

All things are burning, know this and be released.

82 Benz 240 D, Kuan Yin
12 Ford Escape 4wd

You're four times

It's hard to

more likely to

concentrate on

have an accident

two things

when you're on

at the same time.

a cell phone.

www.kiva.org It's not like there's anything wrong with feeling good, is there?

Dude, did you remove the Alda? I never saw a reply to this question. It's always the Alda. At least it was on the three I've had that had your exact symptoms. That's the first thing I do.

I love that Alda. I've gotten so many great cars for a song because of that thing.

__________________
What Would Rudolph Do?
1975 300D, 1975 240D, 1985 300SD, 1997 300D, 2005 E320 , 2006 Toyota Prius

Are you suggesting to remove the ALDA altogether? Or bypass it? Or...?

I've heard of people adjusting it to get more power (at risk), but I've never heard of people removing it entirely.

If I missed an already stated comment, my apologies ...

In the AM, when the car sat overnight, engine cold.

Does the car fire right up?

Does the engine idle smoothly initially?

Have you operated the throttle linkage by hand while the car is in park? If so, does it rev up? Does it remain idling after you rev it up a bunch?

So, the distinguishing feature / issue is placing it in gear and trying to drive it?

I don't drive it on a daily basis, it is still in repair mode and I only get to work on it on the weekends as I travel all week for work.

However, yes it does fire right up when cold and it idles nicely.

It does rev up very well when the car is cold and the throttle linkage is operated by hand. It does remain idling after I rev by hand a bunch when cold. I'm not seeing any smoke come out of the tail pipe that would indicate a head gasket issue and the cooling system leak down test and compression test returned good results. I did the compression test cold, maybe I need to do it again when warm.

There seems to be two (possibly connected) issues.

1. It has very little power when driving (when warmed up or when still cold). It way over-revs before shifting and the shifts are very rough.

2. Once it is warmed up, it tends to want to die after revving up. This doesn't seem to happen when it is still cold. This dying after revving when warm can happen after driving or when revving by hand. This issue definitely seems to be a fuel supply problem.

When I get home this weekend, I am planning to replace the cigar hose with a clear line to see if there is air in the lines. I am also planning to unhook the line to the shut off valve to see if there is vacuum misapplied there.

Any other suggestions are certainly welcome.