What could this problem be?
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What could this problem be?
Hi, I have a 2009 audi a4 2.0 TFSI b8 8k2. My car has started to shake and have erratic power while idling and at low speeds. I suspect it is the tensioner or timing/ serpentine belt because the tensioner is moving quite vigorously when idling. I also suspect that it could be a fuel system problem bit the car drives fine when it's in motion. I'd also like to note that I recently changed the cam position sensor because of a misfire I was experiencing, however I did not reset the problem with an obd tool because my obd 2 port is damaged. Thanks
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Joined: Dec 2001
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From: Georgia
Going to be real hard to speculate without a scan for DTCs. If you suspect the timing, you'd need to read the camshaft adaptation intake bank 1 value after the engine is warmed up and been driven and idled a little bit. If below -5°, you need to plan that timing chain replacement.
The serpentine belt for the engine accessories (alternator, power steering pump, A/C compressor) is not associated with timing. It could be the tensioner is worn out. When was the belt and tensioner last replaced? The belt has an 80k miles change interval. The tensioner is only "if it's not well".
If you use your finger to cover the vent hole on the backside of the round cap on the PCV on top of the engine, does the idle smooth out? Idle issues can be due to PCV problems. But can be due to carbon buildup on the intake valves as well as the injectors. Or maybe a dirty throttle body.
As you see, it's a lot of "something somewhere under the hood". :-) You really want to fix that OBD-II port issue; not being able to use a scan tool like VCDS is really going to hamper your efforts.
The serpentine belt for the engine accessories (alternator, power steering pump, A/C compressor) is not associated with timing. It could be the tensioner is worn out. When was the belt and tensioner last replaced? The belt has an 80k miles change interval. The tensioner is only "if it's not well".
If you use your finger to cover the vent hole on the backside of the round cap on the PCV on top of the engine, does the idle smooth out? Idle issues can be due to PCV problems. But can be due to carbon buildup on the intake valves as well as the injectors. Or maybe a dirty throttle body.
As you see, it's a lot of "something somewhere under the hood". :-) You really want to fix that OBD-II port issue; not being able to use a scan tool like VCDS is really going to hamper your efforts.
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