Hi All,

Looking for some advice. I have done a lot of board searching and haven't found the answer yet. Car is an 85 300D with 260K miles on it. Got a good deal on it but it hadnt run in a couple of years. PO stopped driving the car because it had gotten so sluggish.

Car started right up and runs like a top from 0 degrees to 85 degrees ambient temp. Initially it would not rev over 2k RPM in neutral and could barely get up my driveway in drive (1% grade)

- Primary fuel filter changed
- Secondary spin on filter changed.
- ALDA Banjo cleaned and replaced.
- Bypass valve taken out of loop to verify functionality.

Car will now rev to 3k RPM in Neutral but still has no power driving on the road, and cannot eclipse about 10MPH going up hill. However, I can hear the turbo spooling when taking off.
Next on my list is to check / clean the screen in the fuel tank and replace the accelerator bushing on the fire wall.

Curious if anyone has other suggestions that I might have missed.

Thanks!

 

Thanks for the reply! I removed , cleaned, and replaced the strainer this morning. Engine still will not rev past 3k. One additional thing I noticed is that the exhaust is clean until the engine reaches 2900. Once I get to 3000 it will rev to about 3200 and the exhaust gets thick and grey and the engine settles back to 3000rpm where it will hold and smoke all day long...almost like the governor is kicking in.

I checked the accelerator and the linkage is making it to the stop bolt when the accelerator is to the floor.

Took it for another ride and it is still very sluggish but slightly improved with the strainer cleaned.

Please let me know if you have any other ideas. Thanks!!

 

You may want to check for air bubbles in the fuel line at the transparent (primary) fuel filter. I have also heard of air being sucked into the fuel lines through a leaking primer pump. Check to see if you have the primer pump that has a white plastic top that unscrews, and pulls up before pumping. If it does that may be leaking and needs to be retightened by hand. Replace with newer style if it has the older one after solving low power issue.

 

You may also try using a temporary 2 litre fuel source that isolates your regular tank in front of the firewall (quite a few videos on DIY systems) with fresh #2 ULSD in the temporary container.

 

I wanted to follow-up and let everyone know that I got to the bottom of the problem. Thanks for all of the suggestions.

The Trap-ox was plugged and falling apart. It had launched a piece of the ceramic into the exhaust turbine housing blocking at least 75% of the flow to the turbine and creating a bunch of back pressure. Replaced the trap, problem solved. Thankfully the turbo was not trashed. Runs like a champ now!

 

I thought that I had read that those are covered by a MB recall. In any event if DIYing it be careful as there is a corrosive inside and dangerous to handle.