Feels like Engine is Cutting Cylinder(s)

[bushmaster3000]

Under mild to high acceleration it feels like the car drops a cylinder(s). If I'm going 70 MPG and stomp it the car downshifts rev's up to like 5K then feels like it drops a cylinder then continues on to its highest RPM, at this point it runs good. Taking off from a dead stop under WOT it gets up to about 4-5 grand and pulls hard but at this RPM it once again starts sputtering and then acts up. Slams to second gear, gets up in RPM and same thing. Feels like its cutting cylinders. At idle sometimes the car feels like it drops a cylinder and my A/F goes way lean. I'm guessing unburnt fuel?

Here's what I've tried:

-Replaced two coils on cylinders that said misfires.
-Pulled all the plugs and made sure they were gapped correctly
-Fuel pressure good
-Ran logs and sent to Johan, said things were good on his side.
-Going to get a cord for my Trinity to plug into my a/f gauge.


So anyone have advice?
-Maybe Camshaft Positioning Sensor?

Thanks in advanced.

[BJB]

How do you know the fuel pressure is good?

[nyjoed]

belt slipping? not sure that would cause a misfire tho?

[nyjoed]

Originally Posted by BJB

How do you know the fuel pressure is good?

wouldnt it shopw in his fuel pids to johan? or lean a/f?

[Knuckles]

What are your pluggs gapped at and how much boost you running?

[yungsrt]

Tune related?


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[DemonPerformance]

Originally Posted by BJB

How do you know the fuel pressure is good?

He's running a full return style system with twin 405s etc...believe his base is set right at 60~ and is boost ref'd as well

Originally Posted by nyjoed

belt slipping? not sure that would cause a misfire tho?

Can't see it being belt related at his boost level really, only about 9 psi or so

Originally Posted by Knuckles

What are your pluggs gapped at and how much boost you running?

Think he's got them down to .032 at about 9psi ish

Originally Posted by yungsrt

Tune related?

Everything looks good on the tune side...

[bushmaster3000]

Originally Posted by BJB

How do you know the fuel pressure is good?

I have a fuel pressure light in the cabin and mechanical regulator.

[BJB]

Originally Posted by bushmaster3000

I have a fuel pressure light in the cabin and mechanical regulator.

I have a light inside the cabin too that shows that the boost reference is working and turning the full pump to "race mode" but without a fuel pressure gauge you cant be certain. I had a problem last summer were the fuel tank (custom tank) had a blocked vent and causing a vapor lock. Fuel pressure gauge was one of the ways I found it... And the other way was Jersey told be to let it rip with the gas cap removed!

You really cant depend on any bells or lights. A fuel pressure gauge will tell you a lot. Things happen so fast without it your just guessing. With that being said I still havent been able to log fuel pressure with the trinity.

[Knuckles]

When was the last time the jeep was running fine and since then have you done any work to the Jeep?