delta9ine

Alright. I am not a ford guy. VWs are what I'm comfortable with. I'll start by saying I have searched the forums extensively and followed up on some of the info I've gotten, but I'm still stuck.

I just locked out the cam phasers on a 2005 f150 with a 5.4. It now idles pretty rough. If I blip the throttle the revs will rise and then drop again, and it barely catches in time to prevent a stall. If I continue to tease it this way I can usually get it to stall. I'm getting no CELs or anything, but I intermittently will get a P035x code (it seemed to rove. I've gotten cylinder 1, 4, 6, but not consistently.). I have chased those around by swapping coils, checking/cleaning the connectors, etc. I am kind of thinking that these codes are a symptom of my idle issues, and not the actual problem. What could I have done wrong? Could it be a vac issue? I had basically the entire ECU harness and all the vac lines disconnected to do the job, but as far as I can tell everything has been reconnected to the correct locations. If anyone can help me sort this I'll be incredibly grateful. Thanks in advance!

Oh, and I did have an SCT tune done to remove the phasers in the ECU. I installed it and still have the issue, so for now I am on the stock tune just to eliminate any variables.


Edit: could my tune be the issue? Is this how you would expect the engine to behave with locked out phasers and no corresponding ECU tune?

lewissa81

I'm not sure exactly how the engine will run without a tune after locking the phasers. I do know that you need a tune. Your pcm Is trying to control the phasers in order to adjust the time, but can't, so you're going to have issues. Put the tune on first and foremost.

delta9ine

Thanks good point. I figured below 1200rpm it may not matter. But I've reinstalled the tune and emailed the guy I got it from to verify that it is NOT a tune issue because I do not want to be chasing an issue that doesn't exist. I haven't heard back yet.

delta9ine

No ideas?
I think I have ruled out vac leaks at this point. Cleaned MAF and TB. I'm running out of ideas.

Can anyone confirm that VCT is inactive below 1200rpm? If so, then this shouldn't be related to the phaser lockout and I need to keep looking. Correct? It acts the same with the stock and phaser lockout tunes.

tcp2

Just a thought and probably not possible to do, but if you install the lockouts with the phasers locked in the wrong direction, would it cause the problems you describe. I think the phasers aren't activated until above idle, but may be locked the wrong way?

Eric0508

From what I've read, the stock phasers are not active at idle. You sure you got the timing right when the new ones were installed?

delta9ine

Well, the phasers are fully advanced when they are "at rest", which is how I locked them. If you somehow managed to lock them fully retarded, then yeah, Id imagine you're right and you'd get something like this. However, it isn't what I've done here. Good thinking though. That's the stuff I'm after! Thanks!

delta9ine

I'm like... 110% sure. I've done so many timing jobs I quadruple (actually, more) check timing, turning over by hand before I put anything together. I did that with this. Everything lined up, and the marks I made on chain links/sprockets all lined up again. I mean, it is possible something has skipped, but I really really don't think so so I'd like to avoid pulling it all apart to check until I have no other options. But that is exactly how it is acting, you're right. Like it is just a single tooth off or so. Ugh...

delta9ine

I've pulled all the coils again and I'm cleaning them up, boots, springs, wiring connections. Then I'll clean the tops of the plugs and blow out the plug wells. It is kind of behaving the way a distributor system acts when plug wires crack and ground to the block. Is something like that via carbon traces an issue with these?

lewissa81

The boots can degrade over time. The springs inside the boots can corrode. The boots can even form to the specific position and sparkplug they were on, so when you change that, moisture can enter and cause corrosion. Good idea on cleaning the coil contacts. To be honest though, if your getting codes for different cylinders, and both banks, I doubt that would be the issue. Have you checked all your connections to ground? It's a long shot sure, but a possibility.