alentz627

So here's the deal. I got my turbo kit installed a few months back and it was great for the first couple of weeks...Then I started noticing a stumble around 3k rpm when it was cold along with a crappy idle and a loss of boost. After taking a look at it, a crack was found in the intake and after fixing that the idle issue got better and the boost was back to normal.

Since then the stumble has actually been getting worse and it's at the point now where I'm almost ready to give up on the idea of a turbo and go back to stock. Thinking that this all might be due to a crappy tune, I've decided to give it one more shot. I have a brand new set of plugs and I'm taking the car to get retuned next week.

My question though is should I look into this resistor mod for the FIC PNP harness? I'm currently running the AEM PNP harness, but I also have a boomslang harness on the side. My only issue is that I bought the Boomslang harness used and have no idea whether it's the newer version with the resistors already built in or the older one without.

BTW I'm 99% sure the firmware on the FIC is the z104.hex, but I'm comfortable enough to flash it if need be.

paul_dezod

Before you go nuts or spend a ton of $$ and effort on stuff you don't need....DO me a favor. Reset the ECU on the car. Pull the negative terminal from the battery for 1 minute. And see what happens after that.

alentz627

Hey Paul,

I gave that a shot tonight and now the car won't even idle. It's running like its completely untuned-just idle surging and then dying...

roadrunnergt

ecu must relearn.

paul_dezod

Correct.

That_Kid_Ju

Try reloading your tune. It may have gotten deleted after resetting the ecu.

paul_dezod

Agreed. Worth a shot.

alentz627

Thanks everybody. Sorry I've been super busy with work. Sure enough, I just needed to drive it a little and the idle surging calmed down. The car is running fine now, but it's still stumbling between 3.5-4k rpm. It's also throwing a CEL for lean on bank one.

That_Kid_Ju

If you're getting a lean code, check your tune. That's not good. If anything, boost should make you throw a rich code. Also check that there are no boost leaks and that your injectors aren't getting blocked (which could also cause you to lean out).

alentz627

Would it be easy enough to throw more fuel at it at those particular rpms? Sorry, I just don't have much experience on the tuning side of things. Also, the problem seems to get a lot better as the car warms up and it only seems to happen when you ease into the power. If you really get on it then it doesn't stumble at all.

That_Kid_Ju

Throwing more fuel will just get trimmed out by the ecu. If it goes away at wot, sounds like the tune just needs to be tweaked. FIC isn't the greatest at partial throttle. I have a similar problem.

alentz627

What in particular should I be looking for in the tune?

That_Kid_Ju

Doubful you can find anything that jumps out. Probably just needs some fine tweaking. Nothing you can probably do w/o a dyno and an experienced tuner.

paul_dezod

Agreed, a good tuner at minimum

alentz627

Let me start out by saying thank you to everyone who has commented on this thread. You've all been a huge help up until this point. Paul, I went out on a whim and purchased your base map the other day and the car has never run this good. The stumble is 99% gone (I've been out driving it most of this afternoon and have only felt it once or twice. It's also a lot less noticeable then it was before). I'm still going to have the car professionally tuned again (this time by a different shop), but this is an awesome starting point.

paul_dezod

Glad to see that my hard work on that tune worked well for you. I am sure it will need minimal clean up to be 100%. Awesome!!

alentz627

It's beyond awesome. I reset the ecu this morning and after some mild stumbling around its running even better. The check engine light is off and it's going into boost great. The only thing I've noticed is that sometimes it has trouble finding the idle pocket but it's definitely an improvement. Thanks again! Happy Thanksgiving everybody

paul_dezod

Welcome.