Diablosport Forums

This is an 07 GT/CS

OK here is the deal. Went to work Friday, filled up with 93. Didnt notice any problems and car has been running Great. I have a Paxton Novi 1200 and Mike at Dez Racing tuned it. Puts down 412 rwhk with 374 tq and pulls real hard.

Went to lunch and spark knock city when ya get on it. Runs ok with out putting the pedal down.

Drained out the fuel as low as I could get it by removing the fuel pump and draining via a hose.

Filled with 93 at a different station, added some octane boost and dry gas in case there was some crap water left in the right side tank.

Still wont take any wot with out pinging bad ...

Tried reflashing with both the Paxton Tune and the Dez Racing tune. Completely removed my MSD Two Step and checked all my wiring but still a no go.

Any Ideas ?? BTW i dont get a check engine light ??

Bad plugs?
Vacuum leak?
Loose coupler somewhere?
Burnt wire?

mikel wrote:Bad plugs?
Vacuum leak?
Loose coupler somewhere?
Burnt wire?

Changed the plugs, still pulling good vacuum on the guage and idles fine, checked all the connections anyway, checked all the wires and connectors and everything seems just fine.

Thought it might have been a tank of bad gas, but drained it and refilled with 93 and octane boost.

My question, are there any sensors that could be screwy causing this?

If you floor it it seems to bog at as the boost builds and then starts pinging, wonder if it could be a bypass valve as well, not sure what happens when they go out ??

FRP sensor, bad O2 sensors....no codes?

mikel wrote:FRP sensor, bad O2 sensors....no codes?

No trouble codes at all, I do have a narrow band guage hooked up off the left top O2 sensor but it hasnt been an issue. FRP which sensor is that ??

Ok here is a log file, not very long. Just revved it up a few times after driving it for a while. I revved it till it pinged a couple times. Not sure if you can figure anything out from this or not.

Well I think I have isolated down to a lack of fuel when it gets into boost.. So I am guessing the crappy little piggy back pump you get with the Novi kit has gone belly up.. I'll post my findings later today.

It's really hard to see much in that log. There are so many parameters logged I think it killed the resolution. If you do any more logs, hook up the laptop and log with the default Ford dashboard. The log should be much better if you do it that way and it will have the best set of parameters for what you are doing. Make sure you have the latest Dataviewer installed as well, it can be found here: http://www.diablosport.com/index.php?mo ... lay&pid=11 the version is 3.1.8.3

Kev

I have just been logging to the predator and logging all parameters .. Here is a log from a drive around the block, as soon as it starts making boost it starts bogging and if you hold it, it will start knocking .. Got me totally stumped.

it's tough to tell by the datalog because the resolution isn't there. It's like you have alot of params logged. You might be best to get him to take a look at it, drive it and diagnose it. Having a wideband on to verify the A/F helps too. It looked like the knock sensors pulled a bunch of timing near the end but the sensor signals weren't actually that high...

Did it really go into boost on that run? The highest load I saw was 85%ish which is not quite boost... If you send me the tune I can take a look at it too.

Kev

Well I spent the day at Dez Racing in Seekonk. Mike does all my tuning and it had all of us stumped. We finally figured out we were looking at the wrong end. Everything up top was perfect but it wasnt pushing it out the back. Both Cats were clogged up. Runs like a champ now and with the new 3.90 gears I had em install its super quick making 415 at the rear .. Just like everyone said, its gonna be something stupid, and it was. So if you install a 2 Step launch control, get rid of the cats as the two step kills spark not fuel and eventually it will clog them babies up.

Awesome! Good job guys. I totally forgot about checking the cats although it happens every now and then.

Kevin@Diablo

Wow, nice find....

Which would explain my tip in pinging before my O/R X pipe install higher pre cat exhaust temps.