Hey I am having some problems with my mazda motor 6 cyl. long story short car jumped timing bent valves and had the heads done and everything is good to go now it runs good but when you rev it up past 4000 the tach shuts down and throws the po340 code cam sensor a bank one. its at the mechanics now just trying to help and find info. please help with any feedback. thanks

 

Could be not timed properly.
Could be the actual cam position sensor----one on each side.
@ 4,000 rpm is when power kicks in with variable valve timing.

Check your oil control valves as well: Continually varies intake timing and crank angle using an oil control valve actuated by the ECU to control oil pressure. http://www.justanswer.com/mazda/46hw...hatgoesup.html
The engine computer plays a vital role in the engines performance as it adjusts the camshaft timing depending on the vehicle's engine speed and load. In any range of engine speeds only one camshaft position (in relationship to the crankshaft) is optimum for power and economy. Pressurized engine oil is control by the engine computer through an oil control valve which allows engine oil to flow to the cam timing actuator (or phaser), as the oil is forced into the actuator the camshaft timing advances, when the pressure is released a return spring supplies force to return the actuator to standard position. FROM: http://www.2carpros.com/articles/how...e-timing-works
Crank position sensor could also be a culprit as it gets dirty with age as a last resort.

 

Good video on diagnosing Bad Cam Position Sensor: Check Engine Light and Cam Sensor - AutoZone Car Care - YouTube

 

thanks for the info ill check it out

 

so I unplugged the cam position sensors and the car wont even start so I think they might be ok? I think that I also may have a intake manifold issue since it has like a ticking sound higher the rpm louder and faster the ticking is could something have gone wrong inside the manifold?

 

BAD TICKING SOUND USUALLY MEANS BIG ENGINE PROBLEMS LIKE BAD PISTON OR PISTON CONNECTING ROD OR TIMING CHAIN OR VALVES.

PLEASE TAKE IT TO A PROFESSIONAL!

 

Hey, new here, but found this thread while looking at potential solutions to my buddies 04 mazda 6 4cyl

So he is having the cam sensor p0340 tripping all the time, after replacing the sensor, replacing some NASTY what i believe to be original plugs (263xxxkm) cleaning a dirty dirty maf and general things, the code comes back as soon as you rev the car to 4g range. Also the tach also does some crazy things, just just jumping around, the trac/loss of traction light comes on, the traction control light flashes, and these things are in always there till you clear the code.

So my question to useyournoggin, is what do you think the issue is here... im thinking the cam chain tensioner took a puke, and is causing wonky timing... or it jumped a tooth. The engine isnt noisy like a failed tensioner though.

So any and all suggestions, would be amazing

Thanks

 

How confident are you that the battery is good, and that the terminals & cables are free of corrosion? The 1st generation 6 likes to do goofy things with the tach and some of the warning lights if there is a problem in the charging system.

I'd even be pulling and checking the relays in the underhood power dist. box. Early this spring I had a weird, harsh, rough idle situation. But every time it would happen, I could shut-off the car and it wouldn't happen upon restart. I replaced the Main power relay and it's never happened again.

I'd also be checking for vacuum leaks. I just posted in a another thread how I had an idle issue a couple of weeks ago that would throw a CEL at times, but never give a code. I started going through one-by-one and it turned out to be a bad intake seal.

I had a minor ticking issue a couple of years ago. I ran some SeaFoam in the crankcase for however long they recommend, and it's been quiet ever since.

 

Good points by karlt10.

In addition I would check the wheel bearings and the wheel speed sensors. A little dirt or wiggle could send the wrong data to the computer and mess with the traction control/ABS

 

battery is good and did a load test on it, all turns out fine.

As for the wheel bearing/sensor, the thing is, this happens as soon as you rev over 4k... even if your sitting in the driveway