Vvt codes

Testing according to the S.I. for that vehicle. Like you said, every car is different.

It’s called diagnosing not guessing. You have to follow proper testing instructions to be able to come up with an accurate diagnostic, you cannot “assume“ everything is ok. If you need help, you have to post vehicle information, fault code and procedures you’ve done so we can all help you solve the problem.

Darren Before the “parts canon” is even considered, I check the oil condition. Over half the time I have found VVT codes were oil related. Many times the oil was just changed and we learn the wrong viscosity was used. Other times they have a bazillion miles on the oil interval. I’ve found low oil level. I then look at databases for pattern failures. Then I use the SI test procedures. I’ve been…

Si comes up short on most cars, this is why I am asking. For example, let’s say one bank on a v6 engine is intermittently out of time, stuck actuator or solenoid? Or let’s say it’s out of time by a lot and and all the time, rough running the whole bit. Oil pressure is good, electrical is good….

Darren You've posted a great question, let's narrow it down a bit more as I think you were looking for more specific answers. For the sake of the discussion, let's assume you're working on a … LEV II or 2009 and newer vehicle. In order to make this less murky, let's assume that you have a VVT code set. It's reasonable that if this is in your stall with this problem, a code would have…

Outstanding response, that is what I was looking for. There is no easy way to differentiate between a faulty solenoid or actuator in many cases. Communication to customer becomes crucial at this point. Roger that

If it's less intermittent, and you can get the vehicle to act up, (but not every time it's driven) than it's not terribly difficult to diagnose. If you disconnect the solenoid, and the issue occurs, and the solenoid was physically OK, (actually closed, vs. leaking) then you've got an actuator. If it's very intermittent, then Jim's approach is about the only reasonable choice.

Absolutely Tim, thank you.

I normally start by checking oil level and pressure (most of the time there is a data PID for both engine and VVT oil pressure) second try activating the solenoid with a scanner and see what it does KOER if I don’t see a change I will check it KOEO and listen for an audible click. If it doesn’t click then I would start with checking that out. If it does click on the other hand then you are…

Hi Darren, You are asking a generic open-ended question. In that event use generic diagnostic methods and work from easiest to hardest. Test drive and confirm customer concern. Gather codes and review running data to look at any live data for clues. Cam and crank relative positions are important to monitor activity. A fixed or broken actuator is usually a sure sign because the reading stays…

Before doing anything, view and save Mode 6 data, paying careful attention to all results in tests $35 and $36. If you see some results that stick out, make a note. When you’re lucky, the solenoids will fit either bank and can be swapped. If so, go for it. Drive it while monitoring the tests I mentioned in Mode 6. If you had bad numbers before, and the bad numbers move with the solenoid (to the…

If I understand the question correctly, you're trying to isolate if cam position error is due to the VVT solenoid or the actual VVT as the root cause. Assuming chains are not stretched, ie. actual cam position matches desired on one bank or cam/crank correlates on scope. Confirm oil level and condition. If good, remove the VVT solenoid, inspect for metal or blockage and then test for…

Darren, Good monring Sir, I hope this message finds you doing well. Below you've been given some great advice what I'd like to add is a write-up I did on GM's 3.6 Liter V6. This document has some great VVT Explanations and Testing Ideas. I hope this helps,

Jon Great document. Later when I get to my desktop I’ll save your presentation there.

Thank you.

This class is coming up soon and may be of some benefit to you. I've always been very pleased with classes I've taken from John. automotiveseminars​.​com/product/variab…

I use my scan tool and command the solenoids to move the actuators following the data pids for cam movement. If they won't move check solenoids and actuators for sticking or opens, oiling issues, and lab scope for timing issues. If they do move, then I check for chain stretch and jumped timing with lab scope to verify the timing and that the cam is locking back into place on start up. Some…

Darren, I read that it is possible to see the actuator mechanical response with an amp clamp. Similar to an injector. Personally I haven’t had the need to test one since we bought our PICO system three years ago. I was hoping that Jonathan’s link would show an example. Maybe someone has tried it and can share it. Otherwise using a known good vehicle, perhaps an investment of time into self…

Excellent point.

Randall I read that it is possible to see the actuator mechanical response with an amp clamp. Similar to an injector. I would encourage caution with that. First off, what we are seeing isn't movement, it is the most rapid “change” in movement. If the speed of change is relatively the same at all points, then you won't see the characteristic bump. From an engineering perspective, the…

Ill give one example of a VVT diag we did this morning. 2014 QX80 with 5.6 V8. Complaint is CEL on. We have a P0021 (Intake Cam Bank 2 performance fault) that sets immediately. Car runs fine. Scan data really does not help. It gives me a crank angle spec for both intake cams that just moves around with no real data that I feel like I can trust or come to a decision with. I'm sure someone much…

Caleb, Very nice presentation! I believe that I misinterpreted the story that I read a while back. While it is possible to see the movement of the solenoid valve. One would likely have to be in the oil gallery with a pressure transducer to have a theoretical look at the actuator response? It would be nice to avoid the oil pressure issue. About 5 years ago I got involved in a 5.0 Ford that…

Yes, you are correct. What VVT oil pressure galleys need are pressure sensors at the end of the circuit for exactly what you are talking about. Honda uses them for VTEC. GM uses them on the 2.5 NA engine for the variable intake valve lift. Anyway I agree, VVT can just suck at times. I'll share a 16 Evoque 2.0 Ecoboost story that kinda gave me the run around. I helped with this diag over the…