LTFT Issues and Lugging

My BOV is leaking. Tightened a couple of other areas of concern, however my fuel trims are erratic still. A bit better at idle but slowly creeping to 9, nothing higher yet. Under throttle, 12 on LTFT and higher for STFT. My AFR still extremely rich. Could the BOV cause this? I've spent the last day boost leak testing and vacuum testing to no further avail.

I went ahead and swapped to the stock BPV, with new gasket. The same issues are still occurring. I really have no idea where to turn. Still seing 9-11 AFR under 1/2-WOT and WGDC at 100 even just revving it in neutral.



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Check your couplers from the intake to the throttle body and recirc tube Downpipe bolts all there? I was also missing one.
 
Raider said:
Check your couplers from the intake to the throttle body and recirc tube Downpipe bolts all there? I was also missing one.
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I went through every single coupler, clamp, and line the past couple of days. Made sure everything was good. I will check my downpipe bolts soon, and also the intercooler.

I noticed now that I am sitting at a -10/-11 on vacuum after switching out my BPV compared to -8.5 yesterday. Before that I was at -7, so if I understand correctly, I am making some progress. Hopefully I can figure out my trims, ans that occasional lug, now.


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Did you use a tester? If not, use a tester and a spray bottle with soapy water.

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Gotta use a tester man. 100% use a tester. at either the turbo or intake. If you're testing the exhaust use a plug on the turbo inlet and duct tape a smoke machine to your exhaust or use an vacuum in blow mode and spray for leaks.
 
Raider said:
Did you use a tester? If not, use a tester and a spray bottle with soapy water.

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I used a boost leak tester, yes. Attached it directly to the TIP. Also used a bottle of Windex which showed the bubbles at the BPV. My next step is building a smoker.

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You did a pressure test...and pulled on the pipes to simulate actual motion of the engine? You know anyone around to temporarily swap the o2 sensor with?
 
jsmith said:
You did a pressure test...and pulled on the pipes to simulate actual motion of the engine? You know anyone around to temporarily swap the o2 sensor with?
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Yeah, rocked the hoses as much as I can. The thing that's mind boggling, too, is the lug I get happens 99% of the time only from 1st to 2nd.. And unfortunately, I do not. I'm down in Phoenix if anyone in here can chime in.


Also, I'm about 35 miles in since resetting ECU. My LTFT is reading a 7.~, STFT still varying to +/-25 and Waste Gate Duty spikes to 100 under a quick rev.

Edit: I did a small pull and hit positive 28 STFT. I've read STFT under WOT are irrelevant, is this true? Even so, when I blip throttle LTFT goes to a positive 12.5

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So guys i was looking at a new datalog tonight. My HPFP is jumping all over from low 1700 to high 1800, with two dips into high 1600. All while under WOT. I redid the fuel pressure relief valve test when the car was nice and warm after a 40 mile drive and my pressure Is dropping rather than building. Could my trims and lug be due to the relief valve? Maybe injector seals?


[doublepost=1541407813][/doublepost]This is my latest log if anybody can take a look. Much appreciated.

Also, looking back at some of my first logs when this lugging started happening, my LTFT/STFT were within spec. LTFT no higher than 2.4 and STFT at a -6.0 as its "highest" value.
 

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xsixx23 said:
So guys i was looking at a new datalog tonight. My HPFP is jumping all over from low 1700 to high 1800, with two dips into high 1600. All while under WOT. I redid the fuel pressure relief valve test when the car was nice and warm after a 40 mile drive and my pressure Is dropping rather than building. Could my trims and lug be due to the relief valve? Maybe injector seals?


[doublepost=1541407813][/doublepost]This is my latest log if anybody can take a look. Much appreciated.

Also, looking back at some of my first logs when this lugging started happening, my LTFT/STFT were within spec. LTFT no higher than 2.4 and STFT at a -6.0 as its "highest" value.
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If your valve is not holding it would def fuck with your fuel. Mine was stuck open and I could only build 120psi at idle and if I tried to WOT the car would cut out as there was no fuel there. It's not too hard of a swap. When I took my old one out I could blow right through it and it is not supposed to crack until 1900 ish psi.
 
Do not use windex again. The ammonia can accelerate deterioration on some rubber and plastic. Get a spray bottle from lowes or home depot for $2, drop a tablespoon of liquid dish soap in, and top off with water. Done.

A low pressure smoke tester will help you find "mystery leaks" that you cant seem to find, since you will visibly see where the smoke is coming out of.

A boost leak tester you can use to test max capacity of your turbo system, and use soapy water to check for even the smallest of leaks.

A boost leak tester, you need to hit the leak with soap to find it. A smoke tester is usually only good for low pressure. Ideally a high pressure smoke tester would kill two bird with one stone, but finding a medium to burn something that can hold pressure up to 40lbs is not as cheap to make.
 
JohnnyTightlips said:
If your valve is not holding it would def fuck with your fuel. Mine was stuck open and I could only build 120psi at idle and if I tried to WOT the car would cut out as there was no fuel there. It's not too hard of a swap. When I took my old one out I could blow right through it and it is not supposed to crack until 1900 ish psi.
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Would it fuck with my trims, do you think?

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Mauro_Penguin said:
Do not use windex again. The ammonia can accelerate deterioration on some rubber and plastic. Get a spray bottle from lowes or home depot for $2, drop a tablespoon of liquid dish soap in, and top off with water. Done.

A low pressure smoke tester will help you find "mystery leaks" that you cant seem to find, since you will visibly see where the smoke is coming out of.

A boost leak tester you can use to test max capacity of your turbo system, and use soapy water to check for even the smallest of leaks.

A boost leak tester, you need to hit the leak with soap to find it. A smoke tester is usually only good for low pressure. Ideally a high pressure smoke tester would kill two bird with one stone, but finding a medium to burn something that can hold pressure up to 40lbs is not as cheap to make.
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The more you know.

I built a boost leak tester already, using the nator diy method but will give it another go at trying to find a leak.



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JohnnyTightlips said:
It messed with mine enough that I got a cylinder 3 misfire code so....... and that was at idle.
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I have zero codes atm. I warmed it up just now, and first KOEO fuel pressure rose as normal. Second, it dropped around 10 psi then started rising. Third time, it is continuously falling.


Also, I was pumping my brakes to see how it affected my trims and as I pumped, my AFR hit a 17.9, and STFT pegged at positive 25.


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xsixx23 said:
I have zero codes atm. I warmed it up just now, and first KOEO fuel pressure rose as normal. Second, it dropped around 10 psi then started rising. Third time, it is continuously falling.


Also, I was pumping my brakes to see how it affected my trims and as I pumped, my AFR hit a 17.9, and STFT pegged at positive 25.


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What is idle fuel pressure when the car is hot?
 
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