93 300D 2.5L Turbodiesel Power Loss - PeachParts Mercedes-Benz Forum

tonystewart · #1 10-22-2003, 12:03 PM

Good day
Last week I took the car from South Florida to Grandfather Mountain NC. The car ran great, 30 mpg, good power until South Carolina. Consistent power for 10-15 minutes then a dog, no power have to floor it, downshift, to make it go at all. Pull over, shutoff the car, crank the car back up, power has returned runs great. Cruise for 15 minutes, power gone again. Pullover, repeat the previous process, power back again.
Once I returned to flat sea level driving the problem disappeared.

Any ideas? I want to drive the car in the mountains this winter and it scares me when this happens going up steep grades.

I replaced the following components in June when this power problem started:
vacuum line from the turbocharger wastegate
3 switchover valves
vacuum lines to egr and flap valve on intake
cleaned egr passage, crossover pipe, intake manifold and ports
vacuum lines to and from switchover valves

The Power ATE Discs and EBC pads worked great coming down the mountains. A lot of fun.

T

asharp · #2 10-22-2003, 01:57 PM

Check your fuel filter, sounds like it's clogged

asharp · #3 10-22-2003, 01:59 PM

By the way-How do you like your 2.5. I currently am looking at buying one. any problems or things I should look for

tonystewart · #4 10-22-2003, 02:48 PM

I guess I should have noted that the Car was serviced by me on October 13th, Columbus Day.

Work done:

Oil & Oil Filter replaced
Primary & Secondary Fuel Filters replaced
Transmission Oil & Filter replaced
Differential Lube replaced
Tires Balanced & Rotated
Replaced Serpentine Belt
Replaced Wiper Blade
Antifreeze replaced and Water wetter added

It was a long day!

T

Rick Miley · #5 10-22-2003, 03:12 PM

This won't be a definitive answer, but may give you some things to think about. The 2.5 and later engines are known for pretty closely monitoring the EGR system and cutting engine power if the computer detects anything wrong. I would expect a Check Engine light if it happened, but hey, you never know.

Another report of similar behavior was when the fuel tank vent was clogged and a vacuum built up in the tank. Easy to check by stopping and opening the filler cap when it happens.

If you find out for sure what caused it, please come back and let us know.

gsxr · #6 10-22-2003, 03:14 PM

Wouldn't be fuel filter or fuel supply, because turning the car off & on won't cure that. My guess is the computer sees something after 15 minutes that it doesn't like, and kills the turbo by keeping the wastegate open (no boost). You could verify this by making it act up again with a boost gauge connected to the intake. Next you need to figure out what signal the computer doesn't like and fix it - could be a flaky/faulty sender somewhere. I'm not that familiar with the 2.5L computer controls, that's why I like my 87!

TimFreeh · #7 10-22-2003, 03:27 PM

As always GSXR is right on the money.......

First step would be to check the turbo boost while the car is exhibiting the low power condition. I suspect the EDS computer is malfunctioning somehow and you do not have any turbo boost - the computer is TOTALLY in control of the wastegate on this car. The EDS computer does have a very good self-diagnotic capability - you will need an impulse counter and a 602/603 engine book to do any good.

If you don't have any idea what I'm talking about I would suggest you take it to a dealer or a good MB shop before replacing any additional parts. That kind of 'troubleshooting' can get very expensive.

Tim

tonystewart · #8 10-22-2003, 03:31 PM

Asharp, I hate it!
It is my wife's car and the only thing I do is work on it. The car was perfect for the first 60k miles. Warranty ended problems began. I document everything I do to this car as well as all the equipment we own.
I service this thing with the finest lubes and the best filters. Didn't matter.
The first thing was the front steering. Ball Joints worn out at 80k miles, Idler arm bushings at 100k
Horns failed at 125k
Replaced all of the following to the rear suspension, 150k, to get rid of a shimmy that made the car look drunk.
Thrust arm Qty 2
Tie Rod Qty 2
Camber Strut Qty 2
Control Arm Strut Qty 2
Adjustment Kit Qty 5
Bolt Kit Qty 5
Outer Control Arm Bushing Qty 2

The engine eats motor mounts. 65k 120k 160k
Alternator shorted and blew up the battery at 125k
Cleaning that dirty manifold every year
The injection pump started leaking from the bottom, oil, and the top, fuel. Rebuilt injection pump and replaced injectors at 167k.
Belt tensioner at 157k Water pump at 154k Clutch Fan 157k
Front Flex Disc at 154k

The transmission started leaking at 140k found leak at 160k required removal of the transmission to plug a leak on the side of the transmission called a factory closure plug, never supposed to leak there. Welded a plug into hole, never leak there again.

3 window regulators to the drivers door.
Blower Motor at 172k

Compared to my 1984 300D with 319k this 1993 is a garage man's companion.

The only thing I find interesting was the timing chain has almost no slack. I think synthetics since new made a difference.

My advice, I would buy a newer w210 chassis, 98-99 turbodiesel.

T

gsxr · #9 10-22-2003, 03:35 PM

wow - sounds like a lemon! Tell you what, I'll do you a favor and take it off your hands for about $4k, allright? Then your problems will be over and you can go W210 shopping!

tonystewart · #10 10-22-2003, 04:21 PM

Dave, ouch that hurt. You remind me of a Dave on the Mercedes Digest group.

Rick, no check engine light, yet.

Tim, thanks for the info. Can a Fluke digital meter work for getting fault codes? I have the engine book and have read the section on testing the 602 engine. Seems simple enough.

Gentlemen, thank you all for the advice. I will report back on the results.

wayne2970 · #11 10-31-2003, 01:02 PM

mine is acting the same way....only I dont have a ck engine
light.

I dont think I have a computer controlling the turbo either.

I reciently plugged the EGR valve because it was singing like a
bird

Wayne

Rick Miley · #12 10-31-2003, 01:09 PM

Quote:

Originally posted by wayne2970
I dont think I have a computer controlling the turbo either.

Yes you do.

TimFreeh · #13 10-31-2003, 03:01 PM

Well at least he should.......

wayne2970 · #14 10-31-2003, 08:02 PM

where should I start...?

I just replaced the fuel filters and thats not it!

Ken300D · #15 10-31-2003, 08:24 PM

Maybe a rubber boost (overboost) control line going bad? Check out the rubber line that senses boost from the intake manifold. Trace it to whatever device(s) it goes through on its way to the ALDA.

Can't be more specific because I don't have all that much experience on this particular engine.

Not sure if anything in this sensor path is electronic or not, but a good point was made about the effects you are seeing with cycling the ignition pointing to electronics.

Ken300D