Not sure if this will help or not, but kinda sounds like similar symptoms.

EECTuning.org • View topic - Why did I run out of fuel, and why so abruptly?

 

Does it go lean? Sounds like you really need a wideband in there.

 

I have an innovate lc1, afr is between 11.5-12 till it starts breaking up then it drops to mid 10s. It happens around 10lbs of boost and mainly at WOT and heavy throttle.

I was out driving around yesterday and I could get it to wrap out to 5800 rpm in first gear at 3/4ish throttle. As soon as I shifted into second it started breaking up.

It would make sense if its the Maf because theres a higher load on the engine in 2nd gear and being an Automatic trans the turbos are pumping out more cfm with the increased load when i shift.

 

It sounds like a tuning issue if you're AFR suddenly drops to 10:1. Is the AFR decent until a certain rpm?

Give us more specifics too please, tuner, motor, MAF size, blower, etc

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afr drops when its breaking up, when its running fine its in the 11.5-12 range.
Like I said, 1st gear is usually Ok, when i shift into 2nd gear itll break up no matter what unless i lift. Usually it happens around 4 grand or at 10 psi.


I have a 1993 ford lightning, stock short block 351w (rebuilt last year), edelbrock e 205 heads, custom cammotion turbo grind cam, vic jr carb intake converted to efi, 75mm t/b, (2) to4b turbos, sumped aluminum cell, -8 feed and return lines, 2 walbro 255 lph pump in parallel, aeromotive fpr, 53 lbs injectors, msd dizzy, Analog 6a ignition box, streetfire coil.
For tuning,
A9l ecu with series 4 pms piggy back, Pro-m 3" blow through maf cal'd for 52 lbs injector and pms.

 

Toss the PMS in the garbage and get some form of a chip to tune the car. PMSs have more problems, when it does have a problem, you will get told there is nothing wrong with it. The one I had got sent back twice to get fixed, I repaired it once, then the last time it crapped out, it went in the garbage like I should have done much sooner.
There are muliple other things that could be causing your problem, but the PMS will crap out on you when you least expect it and half the time you will think it is something else and waste a lot of time trying to diagnose the problem when it is just the PMS. The whole concept is a bad idea.

The PMS may not be the problem, but I would bet money it will give you problems and you probably won't have to use it long before you do have problems. It could be ignition or it could be your just way too rich at the point where it goes to crap. Also check to make sure there is nothing in the MAF blocking the air flow to the sensor eliments or anything infront of the sampling tube that would affect the air flow into the sampling tube or that the MAF eliments are not dirty. Also have you looked at the injector duty cylce when this happens? Make sure you are not close to 99%.

 

Lol a chip? sorry, not "tossing my pms in the garbage" just to get raped on having to get a chip retuned everytime I buy a new add on, next stop after this is a fast standalone or bust.

Ive gone through 3-4 sets of plugs, gapping them multiple times, 2 sets of plug wires, 5-6 dizzies, 2 coils, 2 ignition boxes. I don't think its my ignition system.....

heres a picture of the recent maf routing

 

Lol a chip? sorry, not "tossing my pms in the garbage" just to get raped on having to get a chip retuned everytime I buy a new add on, next stop after this is a fast standalone or bust.

Have you considered a Moates Quarterhorse?

 

this samething happen too me i have a blow thu pro m meter and my 6la 2 box was not enough gap at 25 and went with a msd digital 7 box and a HVC-2 Coil i can gap my plugs at 35 and pull all the way to 7000 if need be and i am running a pms.

 

Not running the street fire coil anymore, or the 6al-2 box. I went with a pertronix coil.

Im starting to wonder if my tps voltage settings in the pms are out of wack I was out driving today playing around and when I just laid into the throttle it would break up. But if I eased into WOT it ran just fine and would shift into 2nd with out breaking up.

 

that coil you have is junk i had that same coil get a good box msd digital 7 box and coil HVC-2 Coil.

 

Ditch the MAF and go with a megasquirt.. cant beat the price and you already have a wideband..

 

its blowing out the spark , I would say upgrade to a different ignition system and try that first