Paxton 1200sl tuning issues

[2NY]

I have a 2005 mustang gt that I put a paxton 1200 on with 39# injectors and a MAFia. I already had hot rod cams and steeda delete plates. Basically im working with a local tuner, and he's sent me out a few tunes now that haven't been working out. The car is throwing a p151 code and its running very lean from what I can tell. It barely keeps at idle and just keeps bogging out.

I pulled my plugs to check them (they are all brand new with the install gapped at .035) and #8 cyclinder was all gunked up (assuming its running extremely lean) while the others came out pretty clean. Also I decided to make sure everything was running properly by putting my old intake back on and loading up my old tune and the car starts up fine and idles fine (just a bit rough and I can hear pinging)

I checked all my vacuum lines and all of my connections. I pulled the injectors to make sure nothing was up with those, they seemed fine. Not sure what else it could be on MY end. and YES I messaged lito

 

[weather man]

Gunked doesn't sound lean. Where do they fall on the chart?

 

[2NY]

Id say it looked like this: It had dark sooty gunk on it but wasn't wet

 

[weather man]

That would be rich or plug not firing all the time.

 

[irishpwr46]

what did you do for fuel delivery?

 

[BruceH]

I have a 2005 mustang gt that I put a paxton 1200 on with 39# injectors and a MAFia. I already had hot rod cams and steeda delete plates. Basically im working with a local tuner, and he's sent me out a few tunes now that haven't been working out. The car is throwing a p151 code and its running very lean from what I can tell. It barely keeps at idle and just keeps bogging out.

I pulled my plugs to check them (they are all brand new with the install gapped at .035) and #8 cyclinder was all gunked up (assuming its running extremely lean) while the others came out pretty clean. Also I decided to make sure everything was running properly by putting my old intake back on and loading up my old tune and the car starts up fine and idles fine (just a bit rough and I can hear pinging)

I checked all my vacuum lines and all of my connections. I pulled the injectors to make sure nothing was up with those, they seemed fine. Not sure what else it could be on MY end. and YES I messaged lito

Does the tuner know what to scale when using the mafia? Have you tried it without the mafia?

Have you datalogged the fuel trims? They will be pegged if it's something to do with the maf transfer. The maf xfer affects fueling and the mafia modifies the maf signal. Since the maf signal is not correct with a mafia then the other components related to fueling need to be scaled the same amount. It's just a long distance guess on my part and there isn't really anything you can do except find another tuner if it's tune related.

Lito is going to be your best bet.

 

[max2000jp]

Do you have a wideband? If not, that would be a good investment.

 

[chaoscentral]

What did you do about the fuel pump? You need either a new pump or a boost a pump, the injectors wouldnt be enough

 

[2NY]

sorry for getting back to you guys late. I figured out it WAS the tune after checking over everything multiple times and knowing I didn't install anything wrong and confirming it wasnt an issue with the engine itself. Im running a KB BAP for anyone who wanted to know, maxxed out as well.

Here's the kicker, after running around chasing this "running rich" in cylinder 8 issue down, I got frustrated and decided to make sure it wasn't the tune my tuner sent me. I uploaded my old tune, which wasnt set up for the f/i but was for full bolt on's. I added 4* of global timing and started it up. IT STARTED UP AND IDLED!! I couldn't believe it. I watched my fuel trims and load and everything checked out pretty good. It was running a bit rich but running and staying at idle (it was still surging a bit and rough) I took it for a ride and it drove pretty well considering the factors.