VagPhillips
Well-known member
I'm stumped, hoping someone much smarter than me can help diagnose this issue.
2005.5 Jetta, 250k
A few weeks ago, car went into limp mode on the interstate. I pulled over, disconnected maf and noticed considerable improvement. I replaced with a questionable spare I had and I ordered a reman maf from local parts store and would install when I got home a few days later. Before I got the new part, car started going into limp mode pretty frequently with maf disconnected or connected.
I got home, installed the new one and there wasn't much improvement. I ordered a new Bosch and returned the reman. After installing the Bosch, the problem persisted. So that's 4 mafs, 2 used, one reman and one new Bosch. I think I safely ruled that out.
In addition to limp mode, I'm also getting sluggish acceleration off the line, not as bad at highway speeds. I'm still getting the Emissions Workshop! warning with my cel light. I can always get out of limp by restarting. Some days the code clears, or at least light and warning go off, but still sluggish off the line.
The only code is P0299 Underboost and the MAF code, although I think that is cleared.
I replaced air filter, fuel filter and the N75 just to rule that out.
My mechanic, quite capable but not a TDI specialist checked vacuum hoses, and any signs of an obvious leak, but suggested I take it to a dealer since he feels a little out of his element with this. The only gurus I know in this area have moved.
Can anyone point me in the right direction for anything else to check before I ruin my lifetime streak of never doing business with a dealer?
Thank you.
2005.5 Jetta, 250k
A few weeks ago, car went into limp mode on the interstate. I pulled over, disconnected maf and noticed considerable improvement. I replaced with a questionable spare I had and I ordered a reman maf from local parts store and would install when I got home a few days later. Before I got the new part, car started going into limp mode pretty frequently with maf disconnected or connected.
I got home, installed the new one and there wasn't much improvement. I ordered a new Bosch and returned the reman. After installing the Bosch, the problem persisted. So that's 4 mafs, 2 used, one reman and one new Bosch. I think I safely ruled that out.
In addition to limp mode, I'm also getting sluggish acceleration off the line, not as bad at highway speeds. I'm still getting the Emissions Workshop! warning with my cel light. I can always get out of limp by restarting. Some days the code clears, or at least light and warning go off, but still sluggish off the line.
The only code is P0299 Underboost and the MAF code, although I think that is cleared.
I replaced air filter, fuel filter and the N75 just to rule that out.
My mechanic, quite capable but not a TDI specialist checked vacuum hoses, and any signs of an obvious leak, but suggested I take it to a dealer since he feels a little out of his element with this. The only gurus I know in this area have moved.
Can anyone point me in the right direction for anything else to check before I ruin my lifetime streak of never doing business with a dealer?
Thank you.
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