Good evening Scotty,
I hope can help me this issue.
I have a 2011 Toyota Venza 4 cylinder.
Code P0302 read. Replaced spark plugs. After about two days’ code came back. I noticed that when I got up to 60 – 65 mile phr the engine light flashes and loses power. I lower the speed and then the light stops flashing and car run good. Now I removed the coils and put them in random cylinders to see if the coil was the fault Car ran good for another two days and the same issue came back, Read code, and it came back as P0302, the same as it was before. Took it to a mechanic and he removed the injectors cleaned them out. Tested current and all good. Checked all wiring and found no damaged wires. He took the car to another friend mechanic and between the two of them could not find what is wrong? Mechanic thinks that a valve might be sticking, said to drive it until the issue get bad enough that theycan find the issue with certainly. Can you suggest what I can do now without having to open up the engine. {black}:idontknow:
What is the mileage on the vehicle?
See below: Looks like you’ve ruled out all the items I would have tried. Scroll down to ‘Mechanical Misfire’ section. Has a compression test been performed on cylinder 2 and how does it compare to the other cylinders?
https://repairpal.com/obd-ii-code-p0302
Loses power at higher speed. I would have said check your fuel filter/pump since you need fuel. Other two things you need are air and spark to run a gas car. But that still doesn't solve your code. And since you also already checked spark, I would also check if you got a air leak specifically on cylinder 2. So compression test and smoke test should tell you the info I believe.
Have a look at the FAQ
You may have an issue with headgasket.
