2G Where is my problem? Fuel pump, Pressure Regulator, or something else

[Mham2k]

So I have had lots of issues tuning issues with be idle so I forced the car to stay in open loop, then magically my issues were fixes I thought.

Fuel: e85, rest is in my car bio

This.workednfor.about 30 minutes, Idle is fine but when I drive the car sputters and goes lean.

Test #1: Over compensate global fuel. This worked for a few miles then guess what, sputtering again.

Test #2: Raise fuel pressure, same thing raise it 10 psi from 43.5. then guess what worked for a while then stopped.

Test #3: Pressurize fpr to see if it raises, yep it raises. Not sure if it is 100% 1:1 but it definitely made the fuel pressure go up.

Test #4: Boost leak test, I only get 13psi when testing at throttle body and hear air coming through the crank case and out.the dipstick. PCV is fine, I assume this was due to it being a new build with about 60 miles on it, rings probably aren't sealed yet. I don't have any smoke coming out of the exhaust. There is some air coming from the top of the fpr, I put Teflon tape on it but need to do another boost leak test to verify it worked. No air coming from anywhere else.

Test #5: Pull the fuel pump and inspect. Not done yet, will do soon

Test #6: Pull and test injectors


No matter what tune is in it, no matter what glob fuel, no matter what I do with the software there is something mechanical wrong. Before I go buy a new pump or a new fpr I would like some smart people to give me some more thing I can test.

It's either a problem with the pump (aeromotive ), the fpr, or a vacuum leak somewhere that I can't find.

Any ideas?

 

[NOSLO2PT0]

When you say you are driving, are you just driving normally in town or are you getting on boost, when the car goes lean? You need to turn the car off and activate the fuel pump and then put 30 psi of air to the FPR. Then see if it is a 1 to 1 rising rate.

Also, what does your wideband read when the car starts sputtering?

 

[Mham2k]

When you say you are driving, are you just driving normally in town or are you getting on boost, when the car goes lean? You need to turn the car off and activate the fuel pump and then put 30 psi of air to the FPR. Then see if it is a 1 to 1 rising rate.

Also, what does your wideband read when the car starts sputtering?

Driving no boost sputters, when I try to go above 2500. Wideband reads lean.

I don't have anything to test to see if it's rising 1:1 but I did push some air through it and it rises. I have a cheap tire pump that auto cuts off that's why I can see exactly. So when I set the pump to 30 and put air in the regulator it rises but not exactly sure how much because it happens and cuts off so fast.

 

[NOSLO2PT0]

We can assume that your base fuel pressure is at 43 psi with the car turned off?

 

[Mham2k]

We can assume that your base fuel pressure is at 43 psi with the car turned off?

Yeah it drops slowly but right after cutting it off, if I cut the fuel pump on with the car off yes it's the same.

 

[Mham2k]

Found my problem, the issue was that my fuel pump oring was almost blown out at the plastic cap was cracked.

I put just the oring back in there and it seemed to solve the problem completely, instead of letting it blowout again, i'm going to replace it with 2 of these.

https://www.dsmtuners.com/threads/o-ring-on-fuel-pump.475316/