VVT Problems: 100$ reward for a solution!! Exhaust targets all 0, intakes no response

[bren5279]

SOLVED!!!

Shoutout to a local car guru friend for figuring it out.
Solution:
It was actually a combination of several things. weirdly enough the stock evap solenoid below the intake (the one you disconnect) was stuck open allowing air to be drawn in acting like a leak, yet when we pressure tested it nothing could be heard. the low pressure caused the high idle but the pressure I guess was compensated for in the tune but also caused vvt lockout on initialization. 2 hours of pressure testing, capping off the intake with a hockey puck, and line rerouting, 5 reflashes later and sucess!!! Hopefully if anyone else ever has this issue this'll help!


Background:

-JDL turbo kit on 2015 manual
-First flash all VVTs worked, second one they didnt, went back to first flash and now they still dont work. All the meanwhile the rpm's are all over the place between 1500-3k when I push the clutch in after cruising.

Symptoms:

-Intake CAM Targets: exactly as expected
-Intake CAM Positions: all hover right around 0 plus or minus 1 degree, no changes regardless of throttle.

-Exhaust CAM Targets: all 0, regardless of throttle change
-Exhaust CAM Positions: all exactly 0

-no CEL's

-no identifiable boost leak

What we've tried:
First flash; all VVT's worked
Second flash; VVT's stopped working and acted as described above
Flashed back to first map; VVT's still not working

Flashed it, idled for 5 minutes, drove for 5 minutes, reflashed it, idled for 5 minutes, then drove and datalogged, still nothing.

What Ive checked:
-All vvt plugs are connected (confirmed several times)
-oil pressure is good
-Solenoids get 12v
-Solenoid ground signal wires are connected to the ecm (confirmed by -voltmeter)

[Kodename47]

See here: http://www.ft86club.com/forums/showp...7&postcount=10


Can't account for the RPM fluctuating. Not an SD based issue either?

[DesertFrs]

Originally Posted by bren5279

Ok, so for the last week, me, delicious tuning, and a very experienced 86 mechanic have been trying to figure this out unsuccessfully and now we're absolutely stumped, so Im offering100$ reward to anyone who can help us figure this out.


Background:

-JDL turbo kit on 2015 manual
-First flash all VVTs worked, second one they didnt, went back to first flash and now they still dont work. All the meanwhile the rpm's are all over the place between 1500-3k when I push the clutch in after cruising.

Symptoms:

-Intake CAM Targets: exactly as expected
-Intake CAM Positions: all hover right around 0 plus or minus 1 degree, no changes regardless of throttle.

-Exhaust CAM Targets: all 0, regardless of throttle change
-Exhaust CAM Positions: all exactly 0

-no CEL's

-no identifiable boost leak

What we've tried:
First flash; all VVT's worked
Second flash; VVT's stopped working and acted as described above
Flashed back to first map; VVT's still not working

Flashed it, idled for 5 minutes, drove for 5 minutes, reflashed it, idled for 5 minutes, then drove and datalogged, still nothing.

What Ive checked:
-All vvt plugs are connected (confirmed several times)
-oil pressure is good
-Solenoids get 12v
-Solenoid ground signal wires are connected to the ecm (confirmed by -voltmeter)


We're all completely stumped and out of ideas to even diagnose what it is. So Im offering 100$ to anyone who can help us figure out what it is.

Hopefully you don't have this issue. http://www.ft86club.com/forums/showp...postcount=2970

The Cam Sproket on the exhaust will pop out and will lose oil pressure causing exhaust cam not to work properly.

[DesertFrs]

Also because you haven't been driving the car no codes have popped up .

[bren5279]

Nope, the car doesnt stall out at all, the only thing it does is when cruising then pushing in the clutch and coming to a stop, it rpm hunts between 1500-3000

Originally Posted by DesertFrs

Also because you haven't been driving the car no codes have popped up .

No, i drove for an hour to make sure, no cel's

we did have a low pressure code and a high idle code but it was due to the map, he changed it and we reflashed it and they went away.

[steve99]

Solve your high idle issue.

the vvt may not become active after an ecu flash/reset untill the car idles at normal speed ie about 750 and speed is zero.

I don't think you need to reflash it just turn it off then start let idle while speed is zero, but idle probably needs to be normal.

As you have no codes its possibly a mechanical problem like air leak or exhaust leak near 02 sensors

Check their is no crap lodged in throttle plate and its closing completely.

check the hoses on intake manifold.

[bren5279]

Yeah that could possibly be, the idle is almost exactly 1400. Only thing is, when datalogging the start, the vvts dont change at all even on the startup.

[cdrazic93]

And my vote goes to cam sprocket!

[woode]

If the TARGET is zero.. that would be the tune, no?

Software/tuning side of things is certainly not my strong point so chances are that I am wrong.. just saying.

[sw20kosh]

How could that be a leak? If the solenoid was stuck open it would just allow the evap line to the fuel tank to be open. But the fuel tank is a closed system no?

How did you fix the stuck open solenoid?

[CoryCooper]

So what fixed it exactly? I'm trying to sort this out on mine right now ��

[geezerbrzeezer]

More importantly, did you pay the guru the hundred bucks?

[Teseo]

Who won the prize?