I've mentioned my P0340 code a few times here. Basically, I only get it if I hit the gas more than half throttle when the engine is cold or hit the rev limiter when manually shifting. There will be a noticable hesitation when it first happens and then my car goes into some sort of limp home mode until I turn off the car for 20 seconds or so. The SES light never comes on, but 95% of the time it just shows a pending P0340. Once it also showed a pending P0011 and once both a P0011 and P0021. Once I clear the pending code(s) the car runs fine again. I have replaced the cam position sensor that corresponds to the P0340 code (bank 1). All three sensors were replaced under the recall when the car had 42,000 miles on it.

Usually if a sensor is bad, it is bad and my car shouldn't even start or would completely die-which was why there was a recall on the sensors. That leads me to believe it could be a software issue instead. Any thoughts on this? Would it be worthwhile to pay for a reflash to see if it fixes the problem or should I look elsewhere?

A reflash might take care of my P0420 code too.

 

Reflash may work. It almost sounds like it's got some E.C.U. issues though..

 

is reflash the same as ecu reset procedure? or do they actually update the firmware?

 

The maf strikes again!?

What ya think? If the car runs too lean under load it'll force it into safe-mode (I've made it do that before). That's my only idea.
I know the codes don't say that...but haha

I blame everything on mafs, apparently...

 

Sorry for the ignorance but if one tries the ECU reflash and it does not work. Then procedes to change the MAF and/or the pre-cats does that then require another flash of the ECU because of the new parts.

Reason why I am asking is I have both the P0420 and P0430 codes and $100 sounds better then $2000 to fix this efficiency threshold issue. But I was wondering if one has to reflash each time they install new parts.

 

No. The dealer should be able to reflash to the latest update.

 

Not pulling a code for the MAF or anything showing a lean condition.

BTW, the only time I get the P0420 code is after several miles of driving at a steady 50 mph. I seem to always get the code when driving on the loop around the city that has a posted speed limit of 45 but everyone goes 50 on it. Lot of stop and go driving or long road trips at freeway speeds, I never get the P0420 code.

 

I always get the p0420 at 50-70mph, very random though. Might get it twice in 300mi or not for 3000mi+.

I don't get any rattling like the po430 so I am not that worried. Sounds like an over-sensitive ecu