[MrScharfenberger]

Did you get the relearn procedure done? I can't remember if this has been mentioned but what catch can setup do you have and are all of the check valves installed the correct direction?

I ended up not having to do the relearn. If the reluctor wheel was too far off it would have kicked a code on the computer. Since it didn't it's fine. It runs too perfect "sometimes" for the timing to be off anyway.

I thought of this and checked it last weekend. It is a Mitsimoto catch can and I have the UPR check valve in place with the valve indeed pointing in the right direction.

While checking the catch can on Sunday I was also looking over everything else. I found a kinked vacuum line behind the engine very low on the firewall. It was is pretty choked off. It is very difficult for me to get my hand down in there because I am large & the space is very tight. I'm going to try to replace/fix the vacuum line this weekend. I sure hope to hell this is the problem. Stay tuned....

 

[MrScharfenberger]

Well fudge... Still stuck at the same place but I'm not convinced it isn't a vacuum problem. 3 questions.

1) Does anybody have a link for a vacuum diagram for a 2015?

2) What engine components are vacuum & fuel related ?

3) What systems are activated or adjusted roughly 1 to 2 minutes after the motor is started when cold?

The reason for #3. My car runs perfect when first started cold for about the first 1 to 3 minutes. Then something "adjusts" and the car will start to run crappy. What could be happening that would allow it to run perfect for a short amount of time when cold and then start having idle problems once starting to warm up? When it starts to have problems the idle will hunt a bit going higher & lower than normal idle RPM. But then engine idle speed will drop to 500 RPM's or less as registered on the tach. STFT will also hit a max at -28.2 I believe. When it does this I can bring it back by tapping on the gas but it will just do it again. 1 in 5 times it will stall.

The two Googleable issues have already been done. That is replace a fuel pressure sensor & the vacuum purge part (not what it is called but all I can remember as I type this).

Thoughts...ideas??

 

[Cyclone390GT]

I think you've already ruled this out but if not...

From Turbosmart

TROUBLE SHOOTING
The following points should be checked if you find that your engine is dipping below normal idle, stalling or if the BOV is functioning poorly. Please note: the following checks will cure 99% of problems experienced with a BOV.
- Check the vacuum hose for splits, cracks, loose connection, kinking or any obstruction – old or fatigued hose may collapse
under vacuum causing an obstruction.
- With the engine running remove the vacuum / boost hose from the nipple in the cap of the BOV, there should a loud hissing
sound. The engine should idle poorly, double check by covering the end of the hose with your finger – otherwise the hose is
blocked.
- Check to see if the BOV is blocked or contaminated with dirt or debris.
- Ensure that the vacuum / boost source is not shared and that the vacuum source is directly from the inlet manifold.
- Check the seal between the compressor cover flange and the BOV. Make sure the supplied O-Rings are installed properly
and the BOV Flange is secured on the compressor cover flange with the 3 supplied screws.
- Ensure the spring clamps are secured on silicon hoses and fittings.
- If the valve does not open properly or is slow to react, it could be due to the mapping of the drive by wire system from such
things as aftermarket chips and engine tunes. Check with the tuner that the mapping of the throttle is the same as OEM.
- The valve may not open if the engine is just free revved. This is due to the drive by wire system. Check that the valve
operates by driving the vehicle.

 

[EC0B00ST]

Have you sent a log to your tuner of a cold start and then stalling out once warm?

Have you monitored the vacuum while it's running/ stalling?

Have you monitored afr while it's running/ stalling?

As far as vacuum/ boost lines, there are the following:

Wastegate controller lines

Bov line ( if you have a vacuum/ boost actuated one)

Fuel purge valve (the thing you mentioned)

Catch can/ pcv connections driver's side

Cam-driven Vacuum pump rear of engine. Line to brake booster

line from black cylinder driver's side to rear of intake manifold

Fueling, you have port injection. Have you checked functionality of the secondary ECU and injectors? It is returnless. There could be air trapped in the rail if the secondary injectors have not been used yet.

 

[MrScharfenberger]

Have you sent a log to your tuner of a cold start and then stalling out once warm?

Have you monitored the vacuum while it's running/ stalling? just by watching the vacuum/boost gauge. No significant changes.

Have you monitored afr while it's running/ stalling? Yes. It remains the same as when idling fine. It moves, not fixed but no significant jumps to lean or rich.

As far as vacuum/ boost lines, there are the following:

Wastegate controller lines

Bov line ( if you have a vacuum/ boost actuated one)

Fuel purge valve (the thing you mentioned)

Catch can/ pcv connections driver's side

Cam-driven Vacuum pump rear of engine. Line to brake booster

line from black cylinder driver's side to rear of intake manifold

Fueling, you have port injection. Have you checked functionality of the secondary ECU and injectors? It is returnless. There could be air trapped in the rail if the secondary injectors have not been used yet.
Port fuel injection is not currently turned on. The injectors are unplugged.

 

[MrScharfenberger]

I'm finally on to something.... The video is evidence of very low fuel pressure during the times it is almost stalling. The fuel pressures are very low the whole time from what I now understand. Still figuring it all out but I'm getting there...

From YouTube Description:
Fuel Pressure Problems on 1st tank of 92 Octane after having run only E85 in the tank for the previous 18 months. Yes it had a 92 Octane tune back in it for the gas being used. About 5000 miles were put on the car while running E-85. Car preformed flawlessly on E-85 the whole time. What could cause this? Fuel pump? Regulator? Some seal that the E-85 killed over time because these cars were never sold as Flex-Fuel cars. Thoughts? Thanks in advance.

 

[EC0B00ST]

Your fuel pressure is in BAR. Your lowside is 87psi and your fuel rail pressure is 580psi. That is higher in both regards than mine at idle. Picture attached.

Edit: Trying to think of other reasons for stalling/ summarizing what has been discussed so far.

Please read through this list thoroughly and spend time going over each individual point.

-Throttle position sensor/ motor/ electrical connector/ wiring

-Fuel canister purge valve and its connection to the intake manifold/ electrical connector/ wiring

-Cam timing set correctly on intake/ exhaust cams and on the crank

-Crank sensor mechanical adjustment/ ecu relearn/ electrical connector/ wiring

-Map sensor seal on intake manifold/ electrical connector/ wiring

-Secondary fuel rail spacer o-rings on engine side, intake manifold side, fuel injector side, methanol bung plugs.

-Catch can hoses: connection to intake manifold, check valve allowing air to flow in the correct direction (toward the intake manifold from the catch can, and if you have a dual valve, the second check valve that goes to the intake before the turbo must only allow air to travel to the intake pipe and away from the catch can), all hose connections, catch can plug and all properly sealed. You have a radium pcv plate now if i remember correctly. This means you needed to add a check valve. The Mishimoto catch can does not have a check valve built in.

-vacuum connection on the rear of the intake manifold proper seal and that hose must connect to its intended connection on the other side of the hose and those components must also be working properly/ leak free

The only vacuum leak you can have will be connected to the intake manifold. There is no MAF sensor so it is isolated to that.

 

[MrScharfenberger]

It’s FIXED!! Woo Hoo!! No doubt about it!!

Basically it was the second kinked vacuum line I found that did the trick. Short video to follow later.

ECBOOST- If you typed all of that for me and didn’t copy and paste from somewhere I sure do appreciate the extra effort. I definitely appreciate the detailed response like that as well. Very helpful. In the end what I found was something that somebody else was supposed to have checked and it is on your list. Damn the luck...

I’ll post video tonight.

 

[EC0B00ST]

Woohoo! I can rest easy knowing you've got it running right haha. Yes I typed that out for you and I hope it can be a resource for others having issues in the future as well. I hope you have some good weather left in the year for you to enjoy the car now. Excited to see the progress moving forward.

 

[Hrc630]

Any news ?

 

[MrScharfenberger]

Any news ?

...yes. Sorry for the long delay. This full time job stuff is really cutting in on my free time.

I thought I had fixed it. I apparently did not. It was running good but then went goofy again. As noted by "Ecoboost" in post #327 my rail fuel pressure at idle is more than double what it is supposed to be. This is why everything is so pig rich and dies at idle. The only way the computer can control this is by changing the solenoid settings in the high pressure fuel pump that is driven by the exhaust cam shaft. I need to talk to the tuner Adam Brunson at Tune+ to make sure the computer setting to control that is correct. If it is then I have a problem with the high pressure fuel pump. I intend to work on this again this weekend. I really think the fuel pump is either broken or not installed right due to the cars ability to run perfect sometimes. If it was the tune it would always do it.


I got a bit disgusted with this thing and just let it sit for months then the Covid crap hit right about when I was going to get back on it. I am apparently an "essential" employee and have been working the entire time. In fact working a LOT more than usual due to the pandemic. Over the winter I put together a GM 5.3 LS motor that is now a 5.7 with a Precisoin 7675 LS Turbo on it. It is going in a 1967 Kaiser Jeepster Commando that is also for Hot Rod Drag Week so I've been busy. Just not busy on the Ecoboost.

 

[EC0B00ST]

From your video of the fuel pressure readings, rail pressure is in line with desired rail pressure so it seems the pump is doing what the computer wants it to do.