Extremely rich WOT, no maf. Part throttle is great,story at 11!

[WSLN 6]

Last season I transplanted my ME-R setup with 75lb injectors and wideband correction over to a milder stock build car, ported irons, stock cam, ball bearing 61 turbo, alky etc. Ac delco cr43ts plugs gapped at .32 as I always have done.
Ran great at idle and half throttle.
Under WOT the car would go off the charts rich (9 and under) after 1.5 seconds at any boost level with and without alky. It would be almost like an ignition cut as the car would feel like it was about to shutoff at that point.
I am pretty sure I checked the ingnition/coil pack with a caspers tester prior and the coils ohm out close to each other. Swapped wideband sensors with no change. M-R on leanest setting.
I sent the ecm to Eric and he ran it in his car and it worked great.
Tested the injectors and they do not leak at all and flow close to each other.
What else should I look for? Ignition issues under load?
When the car blew up last year (gave it back to the owner prematurely saying it was not right at WOT yet, got it back 15 miles later with a mess of bent rods and every spark plug soaked in fuel...)
It is now back together and about to go in the car and don't want to miss anything this round.....

 

[Reggie West]

Are you running a double pump ?

 

[WSLN 6]

The car is a single hotwired Walbro 340. Fuel pressure at 43psi vac off. Stock rails and lines.

 

[Bigjsn250]

I see XFI in your sig, can you see injector pulse with and duty cycle when this happens?

 

[WSLN 6]

This is on another car, stock modded ecm with Directscan on it. Unfortunately I did not have the laptop connected when it happened. I will this round for sure...

 

[Bigjsn250]

This is on another car, stock modded ecm with Directscan on it. Unfortunately I did not havethe laptop connected when it happened. I will this round for sure...

ok gotcha, I bet once you see a log, the problem will stand out.

 

[WSLN 6]

I am hoping so, not sure how I could even duplicate the problem, maybe ignition failing under load?

 

[Amelio]

modded ecm for injectors correct?

What chip are you using?

Has there been any changes to the fuel lines especially the return? Also if the tune checks out good check your return line for clogs or any type of restriction.

 

[WSLN 6]

Modded ecm, Turbotweak cheap wth wideband correction. Ecm and chip tested good. Ran flawless in my more aggressive previous setup.
No changes to the stock fuel lines, if the return was plugged, it would have the most problems at idle not wide open I would think.

 

[WSLN 6]

Any other theories guys?

 

[Amelio]

Modded ecm, Turbotweak cheap wth wideband correction. Ecm and chip tested good. Ran flawless in my more aggressive previous setup.
No changes to the stock fuel lines, if the return was plugged, it would have the most problems at idle not wide open I would think.

Not always......I had a restriction in my return line and the car rand great at idle and part throttle but getting into the boost at half throttle or greater ther car would spit and sputter an fall completely fall on its face......I chased my tail for weeks I even sent my chip back to Eric and it was fine. The problem happened so fast I could not see it on the scan master......after I got my chip back from Eric and new it was good.....I did more research and heard of the same issues when the tune was real fat.....so I pulled fuel out from the chip and the car improved........so I started to investigate and found a problem in the return line.

 

[jasjamz]

Correct Map Sensor?

 

[WSLN 6]

3 bar map sensor from the Razor alky kit. I will look into the return line situation as well. I have no problem turning fuel pressure down at idle, so I doubt it is an issue at this point.

 

[WSLN 6]

Running Directscan.....
On tonight's log, I noticed that wideband correction stayed at 128, even though afr was 9.9 to 10.3 and the requested afr was 11.5. Injector ms was 12.2-12.5 using the leanest position (about 47% dc)
Boost was about 18psi with lots of knock (high timing of 25.7 but running 94 octane and meth, never had a problem pushing way more boost with my car and no issues with knock)
The only one of the cells that actually changed in Directscan was the second from the left on the top ( usually 8 but went to 76 under WOT)
Any advice?

 

[Eric Stage I]

Can you send me that directscan log?

 

[WSLN 6]

I will try and do that today, thanks Eric....

 

[WSLN 6]

Files sent to you Eric!