[apexchim1]

I towed my 98 Jetta TDI to my home for the first time today. First day with the car I figure why not jump in head-first. I bought the car cheap because the car had no power. All the forums I've seen say it's either clogged intake or MAF sensor. Since unplugging the sensor had no effect on the way the motor runs, I figured the intake manifold was sooted up. I removed it with no difficulty, and it does seem a little dirty, but the holes in the head where the manifold attach are looking REAL bad. What's the best way to clean these (and easiest)?? Thanks for any input on this subject.:eek

 

[Seatman]

I would be inclined to check the maf too, my neighbours made no difference wether it was plugged in or not but with a new one fitted it's back to its former glory. I'm not sure but you'll have to be careful about dropping any big chunks down into the cylinders.

welcometomyturbodies

 

[chittychittybangbang]

If you clean it you don't want that stuff falling into the engine. Take off the timing belt cover and the valve cover. Rotate the camshaft so that one of the pair of lobes is pointing up like a V. That means that pair of valves are closed. You can now clean that port without stuff falling in. After you scrub it clean, vacuum/blow it out. Then rotate the camshaft so the next pair of valves are closed, and so forth. If using liquid, after you're done, remove the glow plugs, remove the wire on top of the injection pump shut off solenoid so it's not getting fuel, and crank the engine just to make sure that there's no fluid in the cylinder. If so, it can hydrolock the engine.

There are a number of other common causes of low power, see here for more details: http://www.myturbodiesel.com/1000q/multi/low-power-fix-TDI.htm The MAFs on the mk3 are pretty reliable, I'd look at the vac lines and check the boost hoses next.

 

[sprstu]

x2 what Chitty said about the vacuum and air to blow the holes out. Also use some paper towels to plug up the other 3 intake holes that youre not working on. Grab a small mirror to use behind the engine so you can see whats going on back there as well.
Good luck!

 

[apexchim1]

Thanks for the info. To update the story, I successfully performed the cleaning. The intake manifold was extremely sooted up. But after the cleaning, the car was still experiencing limp mode power loss. The MAF sensor was replaced. Still went into limp mode. The N75 was replaced. Still went into limp mode. The turbo and actuator both appear to be like new. Still goes into limp mode. The vacuum lines were replaced. Still went into limp mode. I just got done with a "mufflerectomy." So hopefully the problem will stop now, but I'll keep you all posted. If the car still continues to go into limp mode then is there anyone who would like to buy a cheap Jetta TDI?

 

[Seatman]

Did you check the turbo vanes are moving freely though? They can look nice but it could still be sooted up inside. Also how are the boost pipe connections? Any signs of oil dribbling from any of the connections? Any signs of oil alon the boost pipes? Have you scanned the car for fault codes?