hello all, my wife said her car "lost boost" and she noticed in the higher RPM range while shifting gears large poof of black smoke. i replaced the spongy vacuum line going to the waste gate solenoid.



later that day she said no difference, and the CEL came on, it was a PO243. less than a year ago i replaced the vacuum transducer part #000 545 04 27. i went to MB and bought another one. changed it tonight, and no change. all vacuum lines look good, i sprayed the electrical connector on the transducer out with contact cleaner, then blew it out with compressed air. no change. it is getting SOME boost, but drastically reduced power. with no boost, my 92 300d will beat her car to 50 mph by a car length, so i know what zero boost feels like.



any idea where to go from here?

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'92 300D 2.5
'99 E300TD

How many miles are on it? Is the impulse line at the intake manifold clear where the pressure transducer rubber hose goes? Check to insure that the rubber hoses at the intercooler are in good condition. Also, make sure the cat is not plugged. Is the wastegate linkage easy to move?

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Jim

SON OF A B!TCH!!! it was the impulse line!!! the oil inside the intake made it spongy and soft and pushed it off it's nipple. i had replaced all the rubber vac/pressure lines when we got the car a few years back, looks like it need to give them all another look. last night i checked the linkage on the wastegate via my mighty vac and a mirror. i guess now i have a backup transducer LOL! thanks jim for you information!

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'92 300D 2.5
'99 E300TD

Yw, these cars are really pretty simple to resolve limp home mode issues. The one that took me the most time to troubleshhot was one with a plugged cat.

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Jim

when i bought this car, i took the belly pans off to have a look. i noticed the bottom of the cat had a weld directly in the center, and a weld ring close the the edge of it, about 5 inches in diameter. im guessing someone already drilled a hole in the center for inspection, opened the cat with a plasma cutter, gutted it, then welded the bottom piece back on. it has a throaty idle, i just suspected the cat was gutted, now with this and other threads i know why. thanks again for you help!

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'92 300D 2.5
'99 E300TD