# AT OIL TEMP flashing after a pressure test **URL:** \ **Category:** Maintenance/Repairs\ **Tags:** impreza, subaru\ **Created:** [September 29, 2022, 5:11am UTC](https://community.cartalk.com/t/at-oil-temp-flashing-after-a-pressure-test/186625 "2022-09-29T05:11:34Z")\ **Posts on this page:** 13\ **Page:** 1
**Author:** ![jeff101cartalk\_182362](https://avatars.discourse-cdn.com/v4/letter/j/3da27b/32.png) [@jeff101cartalk\_182362](https://community.cartalk.com/u/jeff101cartalk_182362)\ **Post date:** [September 29, 2022, 5:11am UTC](https://community.cartalk.com/t/at-oil-temp-flashing-after-a-pressure-test/186625/1 "2022-09-29T05:11:34Z")
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. ---
**Author:** ![G32926](https://avatars.discourse-cdn.com/v4/letter/g/ec9cab/32.png) [@G32926](https://community.cartalk.com/u/G32926)\ **Post date:** [September 29, 2022, 9:20am UTC](https://community.cartalk.com/t/at-oil-temp-flashing-after-a-pressure-test/186625/2 "2022-09-29T09:20:47Z")
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. ---
**Author:** ![jeff101cartalk\_182362](https://avatars.discourse-cdn.com/v4/letter/j/3da27b/32.png) [@jeff101cartalk\_182362](https://community.cartalk.com/u/jeff101cartalk_182362)\ **Post date:** [September 29, 2022, 10:07am UTC](https://community.cartalk.com/t/at-oil-temp-flashing-after-a-pressure-test/186625/3 "2022-09-29T10:07:49Z")
Just did that. We also checked the transmission fluid level, it’s good. Thank you for offering assistance. ---
**Author:** ![ok4450](https://avatars.discourse-cdn.com/v4/letter/o/e9bcb4/32.png) [@ok4450](https://community.cartalk.com/u/ok4450)\ **Post date:** [September 29, 2022, 11:37am UTC](https://community.cartalk.com/t/at-oil-temp-flashing-after-a-pressure-test/186625/4 "2022-09-29T11:37:32Z")
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? ---
**Author:** ![jeff101cartalk\_182362](https://avatars.discourse-cdn.com/v4/letter/j/3da27b/32.png) [@jeff101cartalk\_182362](https://community.cartalk.com/u/jeff101cartalk_182362)\ **Post date:** [September 29, 2022, 2:31pm UTC](https://community.cartalk.com/t/at-oil-temp-flashing-after-a-pressure-test/186625/5 "2022-09-29T14:31:34Z")
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. ---
**Author:** ![G32926](https://avatars.discourse-cdn.com/v4/letter/g/ec9cab/32.png) [@G32926](https://community.cartalk.com/u/G32926)\ **Post date:** [September 29, 2022, 3:36pm UTC](https://community.cartalk.com/t/at-oil-temp-flashing-after-a-pressure-test/186625/6 "2022-09-29T15:36:57Z")
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. ---
**Author:** ![VDCdriver](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/vdcdriver/32/30_2.png) [@VDCdriver](https://community.cartalk.com/u/VDCdriver)\ **Post date:** [September 29, 2022, 3:44pm UTC](https://community.cartalk.com/t/at-oil-temp-flashing-after-a-pressure-test/186625/7 "2022-09-29T15:44:33Z")
> [@G32926](#): > > Absolutely nothing to do with transmission vacuum or pressure. 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. ---
**Author:** ![Tester](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/tester/32/15976_2.png) [@Tester](https://community.cartalk.com/u/Tester)\ **Post date:** [September 29, 2022, 4:29pm UTC](https://community.cartalk.com/t/at-oil-temp-flashing-after-a-pressure-test/186625/8 "2022-09-29T16:29:33Z")
The flashing AT OIL TEMP light may indicate that there’s a problem with transmission control module. > **[At Oil Temp Subaru: Meaning, Causes & Subaru AT Oil Temp Light Flashing...](https://autovfix.com/at-oil-temp-subaru-at-oil-temp-light-flashing/)** > > You are driving and suddenly the AT Oil Temp Subaru light started flashing it could mean a couple of things and we are discussing the a/t oil temp triggers right here. Yes, most people know that oil is what Tester ---
**Author:** ![G32926](https://avatars.discourse-cdn.com/v4/letter/g/ec9cab/32.png) [@G32926](https://community.cartalk.com/u/G32926)\ **Post date:** [September 29, 2022, 5:35pm UTC](https://community.cartalk.com/t/at-oil-temp-flashing-after-a-pressure-test/186625/9 "2022-09-29T17:35:52Z")
None have that information was in his post. ---
**Author:** ![VDCdriver](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/vdcdriver/32/30_2.png) [@VDCdriver](https://community.cartalk.com/u/VDCdriver)\ **Post date:** [September 29, 2022, 6:45pm UTC](https://community.cartalk.com/t/at-oil-temp-flashing-after-a-pressure-test/186625/10 "2022-09-29T18:45:37Z")
> [@G32926](#): > > 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. ---
**Author:** ![George\_San\_Jose1](https://avatars.discourse-cdn.com/v4/letter/g/e5b9ba/32.png) [@George\_San\_Jose1](https://community.cartalk.com/u/George_San_Jose1)\ **Post date:** [September 29, 2022, 9:53pm UTC](https://community.cartalk.com/t/at-oil-temp-flashing-after-a-pressure-test/186625/11 "2022-09-29T21:53:50Z")
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. ---
**Author:** ![Cavell](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/cavell/32/43396_2.png) [@Cavell](https://community.cartalk.com/u/Cavell)\ **Post date:** [September 29, 2022, 10:12pm UTC](https://community.cartalk.com/t/at-oil-temp-flashing-after-a-pressure-test/186625/12 "2022-09-29T22:12:58Z")
A scan tool would read the trans temp. Good 1st step to figure out issue. ---
**Author:** ![Nevada\_545](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/nevada_545/32/41232_2.png) [@Nevada\_545](https://community.cartalk.com/u/Nevada_545)\ **Post date:** [September 29, 2022, 10:41pm UTC](https://community.cartalk.com/t/at-oil-temp-flashing-after-a-pressure-test/186625/13 "2022-09-29T22:41:50Z")
> [@jeff101cartalk\_182362](#): > > It was recommended in this forum to get a vacuum test. I asked for a vacuum test. 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.