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MKIV Supra 2JZ-GTE VVT-i with a strange Cam position issue

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Hi, I helped a customer get his newly built engine up and running.

On sunday the 13/3 we started it up and it idle perfect and everything was smooth. Checked for leaks and got it up to temperature before doing the first oil change.

Everything looked good.

Changed oil and filter, and started it up for the run-in process however this time we heard a "knock/Mechanical" sound from around the VVT-i gear so we shut down and started to investigate.

Could not find any issue and restarted the vehicle and the sound was gone.

Took the car out with a 3rd oil change and did some mild running for 25-30 minutes with some light engine braking etc..

went back, let the car idle for a minute, checking for some more leaks then shut it down. changed the oil and filter again with no issues, started it checked oil pressure and shut it down.

The day after we went about to start tune it and this is STRANGE.

The car starts but idles Rich and misfires only at idle while free-revving works fine.

vvt Cam position sensor has suddenly started to show 40Degree while asking for 0 at idle.

Checked timing,checked intake cam, checked ECU settings, NOTHING has changed since sunday to monday, i even have the backup file from BEFORE and after and they are all the same except a few sensors regarding coolant temp and IAT that we changed with the new build.

I'm out of ideas short of ripping off the head and Check the valves.

i have sen this try swapping out the vvti solenoid and or the vvti gear they do have issues from time to time, there is also a filter in the oil feed line that should be checked cleaned and refitted.

basically the only way the cam timing can move is enough oil getting past the solenoid to make it move or the vvti gear is sticking when it is switched off

Seems strange, it's a brand new VVTI gear and also solenoid but we will recheck everything and switch out to the old solenoid, and also check the filter.

Can you post your map ? And a log