Rough starts and slow acceleration
I've been having a few problems with
my mk4 jetta. Lately after the car hasn't
been started for 8 or more hours it
starts really rough and dies unless I rev
it while it evens out. Then it idles and
starts fine after that. The second
problem I'm having is with acceleration
from 40mph or so and beyond it
seems. I can put the peddle all the way
to the floor and it will accelerate 1
mph for every second, then all of a
sudden the power will come back the
next time I drive it. It isn't throwing any
error codes and there hasn't been any
CEL light on from the rough starts. I'm
stumped. Any idea on what it could
It sounds like you have got a mass air flow sensor bad, or a throttle positon sensor that has gone bad.
Alright I think you are on to something with the TPS. When I'm in 5th gear and floor it the scanner says the throttle percentage is only at 29- 30%.
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