Subaru Impreza 2018
74,000 miles
The AT OIL TEMP light is flashing. This light only appeared after a pressure test was performed. The light flashes even when the engine is cold.
Thank you in advance for your help.
Update 1: Transmission fluid level is good.
The only advice I can give you is take it back to the shop that did the test. Mechanic might have left a sensor disconnected.
Just did that. We also checked the transmission fluid level, it’s good.
Thank you for offering assistance.
Since this is likely a CVT transmission I might ask whether the fluid has ever been changed. The level being good means nothing. Fluid additives break down and IMO a CVT should have the fluid changed every 30k miles or so.
You say the light only appeared AFTER a pressure test was performed so I might ask the reason for taking the car in originally. Transmission shifting oddly, noisy, or what?
Yes it is a CVT. I have owned the car for 2 years and have not changed the fluid. I doubt it has been changed.
I also have P0018 code. It was recommended in this forum to get a vacuum test. I asked for a vacuum test. They did a pressure test.
When you took it back, what did explanation did they provide?
P0018–
Crankshaft Position- Camshaft Position Correlation (Bank 2, Sensor A).
Absolutely nothing to do with transmission vacuum or pressure. You need a much, much better mechanic.
Either a good independent shop or a Subaru dealership. Expect to pay for a diagnosis.
The OP requested a compression test of the engine, as a result of some problems probably relating to lax maintenance and resulting timing chain problems. Apparently, the mechanic did a manifold vacuum test on the engine, instead.
In any event, neither a compression test or a manifold vacuum test of the engine would have anything to do with a transmission problem.
The flashing AT OIL TEMP light may indicate that there’s a problem with transmission control module.
Tester
None have that information was in his post.
If you had been following his other posts about his car problems, you would have known about that info.
My guess, the flashing transmission fluid over-temp warning light unrelated to prior engine diagnosis, coincidence. Trans problem likely either a faulty temp sensor, transmission electronic controller, or wiring/connector problem.
As far as the original p0018 problem, a compression test or an intake manifold vacuum test, both could be helpful for diagnosing a valve timing problem. The latter is easier to do, so it would make sense to start with that one.
A scan tool would read the trans temp. Good 1st step to figure out issue.
Manifold vacuum might indicate there is a problem but this won’t get you any closer to a diagnosis of the valve timing malfunction. What will you do with the values they provide?
Tell the repair shop that the check engine light is on and you need a diagnosis and estimate of repair. There is a diagnostic procedure for checking the camshaft timing controls.