I am the new owner of a 1991 300d 205000 on the clock when I purchased it the power seemed to be down do I filled up with a tank of b100 and noticed some improvement two tanks of 100 and 2 cans of diesel engine purge for the injectors I went from about a 24 sec o – 60 to a 17 sec 0-60 still not where it should be.

So I have gone on and check the lines from the intake to sensor to enrichment valve to make sure there was not restriction all seems well. I pulled the intake hose of the turbo to inspect and found the turbo tighter than I suspected as a mater of fact when I compare it a truck turbo it seems bad. When I spin it with my fingers it stop immediately not free spinning when you run the engine with intake boot off so you can see intake wheel it seems to spin fine but when you shut down the engine the turbo act more like its gear driven off the fly wheel than anything. You can hear my turbo on my 6.0 when you are walking in the house after you shut it off. I pulled off a friends 93 300d intake hose and his felt just like mine. “His car does run better” He posted here somewhere and asked about it and someone told him that was normal for that turbo. I have no excessive play no bad signs of wear on the intake wheel.

I hooked up a boost gauge today to see where I was and here is what I have. Max boost 4 psi at 4500 rpm comes off of 0 at around 2700 rpm does anyone have any idea where to go next. The waste gate seems closed with the linkage when I operate the throttle both the intake and waste gate seem to work. I suspect a leaky egr valve but wonder if there is a better way to know for sure with out throwing parts at it. Thank you for your help.

It's probably not getting enough fuel, many typical problems there. Without fuel, it won't develop heat/exhaust/boost.

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Gone to the dark side

- Jeff

Any good idea how to check how much fuel is being requested or deliverd

Do a search on overboost protection valve/sensor. They get plugged up with soot and can cause havoc with the turbo. Had problems with mine for a year until my mechanic unplugged it. My car now runs like a champ.

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'91 300D 2.5 Turbo 330K
'00 VW TDI Golf, 190K
'67 BMW R50/2
'73 Norton Commando Interstate

The computer is probably holding the wastegate open because it's throwing a code. Do a search for EDS and you'll find all sorts of people with the same problem (including myself a while back). Of course, also check the usual things such as filters, the overboost switch/valve, and the fittings and hoses to the overboost valve and ALDA. If those are all OK, dig into reading the EDS codes and tracking down what sensor or transducer has croaked.

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Dale

http://i52.photobucket.com/albums/g1...MG_2277sig.jpg

1990 300D 2.5 Turbo -155k
2000 E430 - 103k
2014 Jeep Grand Cherokee Ecodiesel 4x4 - 11k
2014 VW Passat TDI SE - 7k Bro's Diesel
2006 E320 CDI - 128k Pop's Benz

Pre-glow - A moment of silence in honor of Rudolph Diesel

Start out by changing the oil and filter and use a 15W40 Synthetic oil like Mobil 1. This should make the turbo spin easier. Mine did like yours, felt tight, and the Mobil 1 made a big difference.

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84 500 SEL (307,xxx miles)

One thing i noticed is the waste gate starts to open as soon as you start the engine

How do you know that?

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For Sale: 1982 MB 300TD
1995 Chevrolet Suburban 6.5TD

Sold: 1980 IH Scout Traveler- Nissan SD33T Diesel

The wasegate should be open when the car is off since it is vacuum actuated. Add a vacuum signal and it closes. With the car off, the transducer controlling it does not get power, and therefore the actuator does not get vacuum, so it stays open.

The only way you'll be able to see the wastegate actuator in operation is if you were under the car, as it is on the bottom of the turbo. Are you sure you aren't looking at the intake butterfly valve just downstream of the turbo?

Also, it should close when the car is started.

__________________
Dale

http://i52.photobucket.com/albums/g1...MG_2277sig.jpg

1990 300D 2.5 Turbo -155k
2000 E430 - 103k
2014 Jeep Grand Cherokee Ecodiesel 4x4 - 11k
2014 VW Passat TDI SE - 7k Bro's Diesel
2006 E320 CDI - 128k Pop's Benz

Pre-glow - A moment of silence in honor of Rudolph Diesel

Ok I have read the codes and the are as follows 9, 2, 3, I have cleared codes and codes remained gone after 15 min test drive. My mistake on the waste gate I thought it opened on vacuum but I am backwards when the car is idleing the wastegate opens and from what i can tell if you increase idle the wastegate closes at the same time the intake valve closes, I am wondering about the egr if its stuck open? Thank you for your help as i dig deeper

Ok i supplied direct vacuum and it runs great so now i have the valve ordered to replace