2010 Mazda CX-9 Mazda CX 9 engine tap or knock. Valve train or emissions?
Mazda CX 9 engine tap or knock. Valve train or emissions?
What is your question?
I have a 2010 Mazda CX 9. I believe the standard engine is a Ford V 6, with a Mazda top end.
The car has over 140,000 miles. The car developed something like a valve tap or knock.
1 )At low RPM and when the engine was just started, the motor would make a noisy tap only when a) moving and b) I stepped on the accelerator.
2) The noise would stop when idled, at high speed, or after the car warmed up.
3) Now the noise manifests itself when the car is in neutral and I step on the gas.
4) The noise is worse than a valve tap, like a slap or a fan gone haywire.The noise can be heard from twenty feet.
5) There is no slap/knock/tap at engine start in the driveway, even if I step on the accelerator. The car has to be put in motion.
So might this be a) actuator failure, b) intake problem, c) emission control issue?
What makes this problem better or worse?
stepping on the gas.
How long has your 2010 Mazda CX-9 had this problem?
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A valve tap can make quite a racket. You could have wear to one or more of the overhead cams in the cylinder head, one of the cam followers may have become dislodged -- it's way too hard to tell without getting into the noise in person and trying to pin point the source.
Any of these Ford derivative overhead camshaft engines can throw a roller even due to the use of the wrong viscosity of engine oil. With your mileage, though, it's very hard to know what might be going on without a hands on listen and likely partial tear down.
Thanks for your reply. The only reason I wonder about that is because there is no valve tap at idle, and it can disappear unexpectedly while driving. The tap is correlated to engine RPM, but it can (weirdly) disappear.
Maybe I should get an engine stethoscope.
Thanks for your reply. The only reason I wonder about that is because there is no valve tap at idle, and it can disappear unexpectedly while driving. The tap is correlated to engine RPM, but it can (weirdly) disappear. Maybe I should get an engine stethoscope.