Cylinder 8 misfire and more...

[A.I.I.Raciing]

I have a friend that works at a Audi, Bentley, Porsche dealership and they have guys that tune the shit out of their cars come in with all kinds of problems. My buddy and all his co workers are always talking about how so and so came in with this problem or that problem, well there ********'s post video's and talk about all the shit they do to there cars and hope the dealership will cover the problems. All the techs and service writers have to do is pull up the web site, plus most of the techs and service writers are into the samething's, so they know what's going on.
I can't tell you how many times I heard car's being flagged because of shit posted on the internet. And it may be only flagged at 1 dealership, but tech's talk to other tech's at other dealerships in the area and word gets around. Plus guys move from 1 dealership to another quite often, at least around here they do.

So what I'm getting at is this, don't forget that others are watching what you write and post on forums.

 

[Raptorguy21]

I feel the same way. I find it hard to believe that a bad O2 sensor would cause a misfire. My Raptor is a 2010 6.2.

All the other codes that were generated had to do with a malfunctioning O2, but I dont understand how that could lead to a misfire.

One of the codes was for "ECM/PCM Internal Engine Off Timer Performance"...I wonder if the PCM has anything to do with the issues. I have learned to take everything the dealership says with a grain of salt.

I don't believe the bad O2 sensor directly affected the misfire, however, with the advancement of todays engines and technologies it would not surprise me if something as small as that would have a great affect engine performance overall, must like a dry, rotted vaccum line back in the only TBI and carb days. I don't think the PCM has anything do with the issue, but since the ECM is a part of the code thats how it shows up.....if that makes sense......

Why is a tune such a big deal? If you don't have a mod friendly dealer, just flash it back to stock before you take it in.

Good to know. For a minute there I was thinking there was a way to detect that a tune had previously been installed or something. I know that GM uses a flash counter in some of their vehicles. I think it started with their diesels but has expanded to other models. Anything like that on our trucks?

I haven't gotten answer directly if they can hook a computer up and "see if your truck has been tuned"......but there are other tricks. One of the first was a computer reset code, much like when you disconnect the battery, your computer resets and is in open loop until you have completed the drive cycle. Sooooo guys who stop a block away from the dealership and take the tune off haven't completed the drive cycle and when they scan it they see that code. Again not saying they can see it has been tuned, but they know something is up.

When I worked as a district service manager for GM, we had pictures of what tunes did to diesels, as far as burnt up injectors and spray patterns on the top of pistons, and I can tell you Bully Dog was the WORST!!!!!.......of course you would be surprised how many guys leave the tuner in the truck or have some type of sticker indicating it was "Powered by (insert turner name here)"

 

[CineSLR]

Not sure if Ford's ecus are the same way but *** (audi/porsche/etc) have a flash counter so they can tell how many times the ecu has been flashed....