Code P0351 Trouble shooting?
 

Been getting CEL upon reaching 7800-8000RPM on Stg 2 pump gas map. The code is P0351. I understand that this code is related to coils. However, I tried to identify the faulty coil via logging misfire on cylinders. There was no misfire shown on any!

I thought of taking the car to the dealer to inspect the issue, but I couldn't reproduce the code on stock tune even after driving her hard for half a tank. Everything was smooth and fine.

My next 2 steps in this pursuit are gonna be:

1- Use a higher octane gas (VP MS019) on stage 2 tune to determine if this is related to our crappy 91oct PG
2- Switch back to Stg 1 tune and use pump gas and rev her past 8000rpm and know if it's a tune or a mechanical related issue


My tuner suggested that it's most probably a mechanical issue. But I want to make sure of that before deciding to remove coils or inspect injector seals.

The car is running just fine with a bit of rough idle on STG 2 map, stock tune and stg 1 are both idling very smooth.

I appreciate any feedback and any suggestions :)

p.s. This is not another tuner-war thread, just a guy with some issues :popcorn:

subscribed

Ummm.... How could you possibly attempt to reproduce a problem seen only at "7800-8000RPM " with a stock tune?

The last digit of misfire codes identifies the cylinder. In your case, it's coil #1, the passenger side front coil.

The code itself is an electrical fault, most commonly caused by a coil starting to fail. If you had failiing injector seals, you would hear a loud popping, and I believe would be more likely to set a P030x code rather than a P035x code.

Easy way to check is to swap coils #1 and #3, and if the code goes away or moves to #3, it's a faulty coil.

Thanks... I guess I'll do so

I thought with hard driving I might succeed :burnrubber:

I was getting this as well. For me it happens when doing 0-125mph pulls. I had it happen on the stage 2 tune and the stock tune. They just replaced it under warranty.

It is just that you cannot GET to 7800-8000 RPM with the stock tune.
You will be bumping against the rev limiter @ ~7400

Coils have their ratings, once you go beyond that they could be damaged. To make it work at load levels not seen at stock or bypass issues with even more aggressive ignition will do it too.
Otherwise there would be no need for aftermarket coils to support higher engine load/power levels.

Well, for his case, if the redline is 600 rpm higher, that would mean that at the highest load, also requiring the highest amp draw would need to fire 10 times more per second?
Yes, you could be right.

So, I started the trouble shooting last night. CEL came back on stg 2 with Race gas, this meant that it wasn't a fuel related issue.

However, a dramatic change to the scenario occurred when I started hearing BACKFIRE in the engine bay during part throttle tapping under load. It was loud and scary! It came on all maps (STG 1, 2 and stock). It's a clear indication (IMO) of injector seal failure. It did not pull a CEL tho.

Car taken to the dealer's for further inspection

Let us know what they find.

So far, they confirmed that it's an injector seal issue. They had a similar issue with another car from my production batch.

Did they tell you why the injector seal failed?