I hope folks still follow this thread.
I've read all 21 pages and followed some advice but I have a few questions.
First, ( have an '01 Golf TDI, 5-speed manual, with 440K Kms on it (~250K miles)
I just finished replacing the tranny with one from an '03 but the job got interrupted in the middle for 3 weeks so I only just got the new tranny in last week. Another story..
So when it's all back together I fire her up and it runs fine for a bit and then totally looses power and a lot of blue smokes come from the tailpipe (blue = oil? and my exhaust ends in the middle of the car just past the resonator so the smoke was coming from there).
Found that the vacuum line from the vacuum pump had severed at the pump side of the rubber line, victim of the tranny job. I cut it off and used a regular hose clamp on the remainder.
However, no joy, no power, surging when I try to accelerate in neutral, lots of blue smoke. Also, could no longer hear the turbo whine which is normally easy to hear due to exhaust configuration. Worried that the turbo went south.
Car was throwing a maf code, 101. Read this thread. Tried out a number of things.
- vacuum hoses look shot. the one to the turbo is chafed but used a hand vac pump and the actuator seems to move the full range.
- vacuum in the "vac" side of the piping is around 20-25 mm Hg. varies with rpm.
- vacuum on the "out" side of the N75 is 5 mm Hg at idle, climing modestly to 8 mm Hg with 2500 rpm and in neutral. Does that sound right?
- pulled the hose off the intake manifold so I could check to see if the turbo was pushing air. It wasn't pushing much at all. So I put my hand vac on the line to the vane actuator (ie, the test above but when the car running) and when I manually operated the vanes, lots of air moved so that sounded somewhat positive to me.
- this morning I pulled the maf (or map or whatever it's called) and it was dirty so I cleaned it with non-chlorine brake cleaner. Reinstalled.
- went for a drive and the car seemed fine... Popped the intake manifold off because I hadn't reattached the hose clamp when I pushed the hose back on. This was deliberate, figured it was a poor mans boost pressure gauge...
- clamped it and it seemed fairly good. Only thing I could feel was some turbo lag that I don't remember being there and sometimes it seemed to have less power than I remember. But I'm pretty hyper-sensitive right now to every hiccup so it could be imagination.
so question. could a bad MAF lead to the symptoms. I mean total loss of power (barely enough to get going at low rpm and takes forever to get up to speed, all the while blowing huge clouds of blue smoke).
does my N75 sound faulty too? any way to be sure?
I'm going to replace the MAF, it's on order, and likely will order the N75 too and replace the hoses while I'm at it but I'm curious if this was the culprit or if I should look elsewhere.
PS. bought my wife an '06 TDI a week before my tranny replacement and spent the last 4 weeks driving it, put 8000 Kms on it with a trip to newfoundland. The BEW engine has a way different torque feel to it and maybe the lag I feel on my ALH is normal and I'm just not used to it... Just went for a test drive and what I feel is a ~1 second lag on the power when shifting.