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UPDATED: Engine cuts out as soon as I get into boost
I've been running this setup for about 3 years. For the most part, it has ran fantastic up until last year when the primary fuel pump died out on me and then the **** show started.
Fast forward to now, when I roll into the throttle it feels good right up to 100kps and then it shutters and cuts out but still keeps pulling, but not smooth how it should be.
So far I installed brand new msd wires, new BR7EF plugs gapped at .020". At .028" gap, the car acted the same. Running stock Ls1 coils.
My hp tuners scans dont show any misfires or spark retard at all.
Below you can see how I have my PE setup. The bottom table is what I had when the car ran good. I was told that I had it ramping in too Rich too early in the rpms so I changed it to what you see in the top table.
Run down on the car 2002 Ws6 6 speed
Forged shorrblock 346, 10:1 compression
Stock 243 heads with double valve springs
Ls6 cam
Ls6 intake
Ls1 Throttle Body
SD tune on e85, 11:1 target wot a/f
80lb seiman injectors
Dual fuel pumps. Walbro 255 primary, Walbro 525 kicks on at 4psi
new -8 feed line
oem 3/8" feed is now the return line.
D1SC Procharger pullied for 15psi.
When the car was running good, I was running dual walbro 255s pumps however I could tell I was close to maxing them out on e85. After filling up with e85 one day, the primary pump died out, got car towed home, car started back up drove of the flat bed, I redid the wiring just to be on the safe side.
I decided to just run one big pump with a KB BAP. So I bought a Walbro 525 pump. After more thinking, decided against the KB BAP and just paired the 255 and the 525 together. Now here I am. Thanks for any advice.
Have you tried going back to the old tune when you said it was too rich on tip in? Your timing falls off pretty hard when youre barely in boost. Your absolute pressure is only a few psi and you chop the timing down to mid teens. That seems very conservative on E85. Your leaner than commanded on tip-in but nothing crazy.
Have you tried going back to the old tune when you said it was too rich on tip in? Your timing falls off pretty hard when youre barely in boost. Your absolute pressure is only a few psi and you chop the timing down to mid teens. That seems very conservative on E85. Your leaner than commanded on tip-in but nothing crazy.
Yes, It was doing the shuddering with the old PE table. I was told by a tuner that I had the PE setup to where it was too rich too early in the RPM range. I was commanding 11.0:1 A/F at 0 kpa and was told I didnt need to have it that rich that soon. So blended it some.
About the timing: Before, when the car was running good, I had the timing at 18* at wot. Ever since it started shuddering and popping out the exhaust, I dropped the timing down to 12* to be safe until I fix this issue. After I installed the new spark plug wires the popping out of the exhaust went away.
Yes, It was doing the shuddering with the old PE table. I was told by a tuner that I had the PE setup to where it was too rich too early in the RPM range. I was commanding 11.0:1 A/F at 0 kpa and was told I didnt need to have it that rich that soon. So blended it some.
About the timing: Before, when the car was running good, I had the timing at 18* at wot. Ever since it started shuddering and popping out the exhaust, I dropped the timing down to 12* to be safe until I fix this issue. After I installed the new spark plug wires the popping out of the exhaust went away.
Yeah 11.0 right when entering boost is too rich. I guess Im curious if you go back to your old timing how it would run too. Just seems odd that youve changed the tune AND had fuel system issues when the problem started. Logging fuel pressure would be useful but the measured AFR looks ok. What do all 8 plugs look like. Did you just do wires or replaced the plugs too? Have you tried a temp gun on the primaries or killing each injector 1 by 1 to see if maybe youre down a cylinder?
Yeah 11.0 right when entering boost is too rich. I guess Im curious if you go back to your old timing how it would run too. Just seems odd that youve changed the tune AND had fuel system issues when the problem started. Logging fuel pressure would be useful but the measured AFR looks ok. What do all 8 plugs look like. Did you just do wires or replaced the plugs too? Have you tried a temp gun on the primaries or killing each injector 1 by 1 to see if maybe youre down a cylinder?
I am logging the fuel pressure. You should be able to see it on my scan file. The plugs I'm running now were brand new and installed back in December. When I pulled them out to regap them to .020", They looked good, maybe a tad lean. I looked for cracks on the plugs but did not see any. But I got brand new plugs being delivered tomorrow just to eliminate them from the equation.
I am logging the fuel pressure. You should be able to see it on my scan file. The plugs I'm running now were brand new and installed back in December. When I pulled them out to regap them to .020", They looked good, maybe a tad lean. I looked for cracks on the plugs but did not see any. But I got brand new plugs being delivered tomorrow just to eliminate them from the equation.
I dont see it logged. New plugs are cheap insurance.
The good news. adjusted my PE table EQ ratios, and installed new plugs gapped at .020" and the car ran great. Smooth and powerful. I made 2 4th WOT pulls up to 4800 and got the AFR error within 1-2%.
The bad news: As Im driving home, I look at my wide band and see it running between 20%-30% lean. I'm pretty sure its the damn Walbro 255 pump going out. I dont know what it is with this things. I buy the ones that suppose to be genuine Walbro pumps. This is like the 3rd pump that Ive had issues with. Maybe they dont like the e85.
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UPDATED: Engine cuts out as soon as I get into boost 
