I've noticed more and more over the months that my '91 744t doesn't have the off the line power it did when i bought it. When i bought it 3 years ago it had 155k. Now its up to 225 and still running good (after numerous agrivating problems at 200k mark till 215k) Anyway, is there anything i can do to get that lost power back w/out doing anything drastic like rebuilding the engine. Any advice would be appreciated. Thanks!

Try this. Pull the plug off your idle motor. If it is oily in there then you are not sending the proper signal to the ECU. The three prong plug goes directly to the ECU and the signals determine air/fuel mix. I cleaned mine out with carb cleaner and regained power. I probably should have used a degreaser. The problem returned and I checked again to find more oil in the plug and electrical post housing. That's due to the oil draining down from the hose that comes off the intercooler hose down to the idle motor under the intake. I would clean the intercooler and all hoses and remove the idle motor to get all the oil out. If there is no oil there then disregard all of the above. I hope that helps. It sure made a dramatic difference in my 87 745T.

Mark

Hi Luke,

In addition to what Klaus has said I can add this: Is the turbocharger original? If so, at that mileage it may be starting to get tired and might not be boosting like it once did. Also, the boost pressure may be backed off as well. I suggest checking the pressure. Another thing that my mechanic and I found out during the rebuild of my B230FT was that it's common for the wategate arm on the Mitsu TD04 to "sag" over time meaning that the wastegate door doesn't seal properly and you loose boost pressure. It's a hard thing to check without at least removing the exhaust downpipe from the turbo. Did you preform a compression test on the engine? Should be fine at that mileage if it's been well cared for, but it wouldn't hurt to check. I hope this helps!
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Chris. Halifax N.S. '91 745Ti, 290K km and '91 745 NA, 379K km.

We assume you have done tune ups. When is the last time you changed the gas filter or cleaned the injectors? Throttle body gets dirty eventhough you throughly cleaned the flame trap. And don't forget the Polish tune up: redline in second gear two or three times at full throttle to clean out some of the carbon build up.

Klaus
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95 854T, 88 780, 88 245, 01 A4 Audi