02 toyota camry 2.4

I have a 02 toyota camry 2.4 when its cold it starts for 3 seconds but it turns off right away you have to turn it over like 4 times then it will start and when it dosnt start it will give you code p1656 only when not starting they already put in a new ocv valve new oil i dont think thats related to what it doe of not starting your help would be apriciated thanks.

wow those variable valve systems can be touchy I guess theres an open or short to ground in wiring harness maybe if you have bidirectional control of oil control valve it would help diagnose it but a scan while driving under different loads might be in order interesting code

I know a precursor to servicing vvt systems may be just changing oil

Thinking outside the square now - VVT relies on cam position sensor feedback to know that it's working. Fault codes are not always what they say they are but I think your first step would be to scope the VVT solenoid and actually see if the duty cycle pulse is falling away before deciding it's the harness. Then think about the possibility of cam/crank timing out of alignment ["stretched" chain/ cam belt jumped teeth]. If it tries to control timing and sees the wrong position from the CAM sensor it may give the same fault.

Don't jump to fast on this one the code is defined as a circuit fault this points to an electrical issue rather than a mechanical issie. As the sensor had already been changed for what we assume is s good part the starting point is close visual inspection of the wiring followed by power and ground checks at the connectors and then tug tests to see if anything drops out. Really a job for a scope or a a graphing to observe changes in the signal when tugging the wiring.

I'm with Andy, I dunno that I'd chase the P1656 just yet. If anything, I'd disconnect the OCV and see if it now starts consistently.

I'd also be tempted to watch injection pulse and spark when cold to see if I'm losing either one. That'd put you in the direction of an input problem.

Just a question (I still have a lot to learn so enjoy getting involved in these discussions) Can the action/inaction of the OCV actually cause the engine to die and not start again?

Desmond6004 wrote: Just a question (I still have a lot to learn so enjoy getting involved in these discussions) Can the action/inaction of the OCV actually cause the engine to die and not start again?

Possibly, IMO. I know my Scion will either crank and not start, or start/stall if the VVT solenoid is PowerProbed wide open. It will also stall if the solenoid is opened at idle. This 2.4L will do the same. As always, there are variable, and not every vehicle will do this.

This Camry's solenoid is power side switched, so the only real way the solenoid could be stuck on is a short to power on the control wire. Unlikely, IMO. Disconnecting the solenoid will eliminate that possibility. The actuator itself (the gear on the camshaft) could be moving unintentionally, but it shouldn't set the P1656 because of that.