Well I have been having a bad break up issue, that I originally though was due to a blown head gasket. Checked everything over and showed no signs of a blown gasket. Changed plugs, coils wires and was throwing no codes, which made this very hard to diagnose! After all that I replaced that only left 3 things on the table... Cam position sensor, Crank angle sensor or ECU. I tried the easiest first, the Cam position sensor, and so far so good! I turned the boost down to 26 psi and finally made a clean pull yesterday... need to retune the car now and make sure everything is kosher.

 

Good to hear Freddie! Hopefully that was your issue!

 

Out of curiosity, I too am having a break up issue at WOT or 3/4 throttle......did the new plugs help this issue at all?

I ask because I replaced my plugs and my car ran almost perfect for awhile (couple of weeks, if that) then went back to breaking up as I mentioned....Wondering if my problem might also be a bad cam sensor?

I have not replaced my coils, wires or cam sensor. I did replace my crank sensor when I did my timing belt a while ago...

Glad you found and fixed your problem!

Didn't mean to jack your thread....

 

New plugs did nothing for my issue

 

where you on stock ecu freddie ? i ask cause a bunch of us where having this problem but we were all on aem

https://www.evolutionm.net/forums/ae...am-sensor.html

 

I've read about a couple cam sensor failures on stock ECU. I think dave buschur was on stock ECU when he had a major mishap due to a bad cam sensor. It seems like when the engine just isn't doing what it's supposed to for no apparent reason, it's probably the cam senor. At least that's how I see it.

 

thanks for posting that link. anyways, the cam sensor basically has to try and figure out timing based on "calculating" degrees off a trigger wheel that has horrible resolution "equal to guessing based off 4 crank revolutions". ill paypal the first person $50 to post how to shut this pos off in aem and run strictly off a proper crank wheel after the engine is started.

 

dave was on aem when it happend and no problem n2oiroc and i would try to get ahold of brad brooks hes very good with aem and helped with the design of the wheel.

 

its not just the stock ecu, its a problem on every tuning platform.

 

Nevermind. I just realized my post was stupid.

 

Freddie how is your evo running now? Hav u retuned it and upped the boost w/o getting break up

 

Well I bumped it up to 30 psi and did a rip, it went a little rich for E85 and broke up for a split second, nowhere near how it was before... I havent had time to mess with my own car much, most of my time goes to customer cars...

 

i was curious cause I have similiar issie with breakups.. after a couple hundred miles on fresh plugs. Except now i pulled a code right at start up twice in a row after fresh plugs and arnd same mileage on those plugs. Misfire Cylinder 2. Going easy thing first and moving that injector to another cylinder. Hoping its the injector! If so finger crossed time to go bigger
if not i'm looking at the cam sensor

 

RE Cam Angle Sensor Failure - the driveability symptoms I experienced were as follows:
- a noticeable loss in low rpm torque
- car felt like it was dragging an anchor
- intermittent hard to start engine; engine would intermittently start then die shortly afterwards

Finally the ECU threw a P0340 code (Cam angle sensor). I diagnosed as per Evo Maintenance Manual - checked cam angle sensor harness resistance and voltage, since this checked out OK, and noting the car had previously thrown a P0340 code, I replaced the sensor, which was the right choice in the end.

The love/hate relationship continues. Good luck diagnosing your problems people!