# Help me with engine issue, cant figure out the electrical issue **URL:** \ **Category:** Maintenance/Repairs\ **Created:** [January 29, 2025, 4:12pm UTC](https://community.cartalk.com/t/help-me-with-engine-issue-cant-figure-out-the-electrical-issue/198874 "2025-01-29T16:12:56Z")\ **Posts on this page:** 15\ **Page:** 1
**Author:** ![Tacos1234](https://avatars.discourse-cdn.com/v4/letter/t/22d042/32.png) [@Tacos1234](https://community.cartalk.com/u/Tacos1234)\ **Post date:** [January 29, 2025, 4:12pm UTC](https://community.cartalk.com/t/help-me-with-engine-issue-cant-figure-out-the-electrical-issue/198874/1 "2025-01-29T16:12:57Z")
Nissan Sentra 2009 2.0 147k mileage I need help trying to figure out what is wrong with my engine. I started noticing power issues and electrical flickering on my dash, headlights, and any lights inside the car. the probably is getting worse. The engine is struggling with power but once I run it it gets better but then the car has shaking or jolting throughout driving. I also seem to have an issue going in and out of 1-2 gear which makes me think there is also a transmission issue possibly. I was getting error codes for a misfire in one of my cylinders and thought maybe replacing there spark plugs and ignition coil would fix the issue. I replaced all 4 and the misfire code went away and the power did get better. Now the electrical issue still remains. What’s odd is when its cold outside or the engine is very cold I have very little issues. no flickering or little and much more power which makes me think it might be a short related to heat. I had the battery replaced and the alternator is testing great. (alternator is a new one put in 2021). Another problem which may be realtered is when I’m slowing down my car as its coming to a stop has a really hard shift to first gear and makes a weird noise almost like the piston in the breaks is locking the releasing. ---
**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:** [January 29, 2025, 4:20pm UTC](https://community.cartalk.com/t/help-me-with-engine-issue-cant-figure-out-the-electrical-issue/198874/2 "2025-01-29T16:20:19Z")
You might want to have someone look into if there’s a problem with the BCM. > **[Bad Body Control Module Symptoms To Never Ignore - Flagship One Blog](https://www.fs1inc.com/blog/bad-body-control-module-symptoms-to-never-ignore/)** > > Some of the bad body control module symptoms can afftect the most important things for your vehicle to be safe such as the dashboard, the warning lights.... Tester ---
**Author:** ![Mustangman](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/mustangman/32/44130_2.png) [@Mustangman](https://community.cartalk.com/u/Mustangman)\ **Post date:** [January 29, 2025, 4:20pm UTC](https://community.cartalk.com/t/help-me-with-engine-issue-cant-figure-out-the-electrical-issue/198874/3 "2025-01-29T16:20:28Z")
What transmission? This has to be throwing error codes. Please list them all in the format P1234 ---
**Author:** ![ledhed75](https://avatars.discourse-cdn.com/v4/letter/l/f6c823/32.png) [@ledhed75](https://community.cartalk.com/u/ledhed75)\ **Post date:** [January 29, 2025, 4:23pm UTC](https://community.cartalk.com/t/help-me-with-engine-issue-cant-figure-out-the-electrical-issue/198874/4 "2025-01-29T16:23:29Z")
Even though the alternator and battery sound “newish”, I’m suspecting an electrical issue. Having said that…what’s the service history on the transmission? Has it had regular fluid changes? ---
**Author:** ![Tacos1234](https://avatars.discourse-cdn.com/v4/letter/t/22d042/32.png) [@Tacos1234](https://community.cartalk.com/u/Tacos1234)\ **Post date:** [January 29, 2025, 4:24pm UTC](https://community.cartalk.com/t/help-me-with-engine-issue-cant-figure-out-the-electrical-issue/198874/5 "2025-01-29T16:24:46Z")
I checked the code this morning and getting a low transmission fluid code. It hasnt been changed since the vehicle had 40k miles. ---
**Author:** ![Tacos1234](https://avatars.discourse-cdn.com/v4/letter/t/22d042/32.png) [@Tacos1234](https://community.cartalk.com/u/Tacos1234)\ **Post date:** [January 29, 2025, 4:25pm UTC](https://community.cartalk.com/t/help-me-with-engine-issue-cant-figure-out-the-electrical-issue/198874/6 "2025-01-29T16:25:18Z")
CTV and only getting low transmission fluid ---
**Author:** ![Mustangman](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/mustangman/32/44130_2.png) [@Mustangman](https://community.cartalk.com/u/Mustangman)\ **Post date:** [January 29, 2025, 4:30pm UTC](https://community.cartalk.com/t/help-me-with-engine-issue-cant-figure-out-the-electrical-issue/198874/7 "2025-01-29T16:30:32Z")
If you have no check engine light, I’d say your transmission is failing. ---
**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:** [January 29, 2025, 4:33pm UTC](https://community.cartalk.com/t/help-me-with-engine-issue-cant-figure-out-the-electrical-issue/198874/8 "2025-01-29T16:33:29Z")
> [@Tacos1234](#): > > It hasnt been changed since the vehicle had 40k miles. Then, it’s overdue. ---
**Author:** ![Tacos1234](https://avatars.discourse-cdn.com/v4/letter/t/22d042/32.png) [@Tacos1234](https://community.cartalk.com/u/Tacos1234)\ **Post date:** [January 29, 2025, 5:52pm UTC](https://community.cartalk.com/t/help-me-with-engine-issue-cant-figure-out-the-electrical-issue/198874/9 "2025-01-29T17:52:24Z")
check engine light is on at it says its the catalytic converter. why is the transmission issue only bad when the weather is hot or the engine heats up. also it sounds independent of the electrical problem. ---
**Author:** ![Tacos1234](https://avatars.discourse-cdn.com/v4/letter/t/22d042/32.png) [@Tacos1234](https://community.cartalk.com/u/Tacos1234)\ **Post date:** [January 29, 2025, 5:53pm UTC](https://community.cartalk.com/t/help-me-with-engine-issue-cant-figure-out-the-electrical-issue/198874/10 "2025-01-29T17:53:23Z")
that will be the next step I guess. ---
**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:** [January 29, 2025, 6:08pm UTC](https://community.cartalk.com/t/help-me-with-engine-issue-cant-figure-out-the-electrical-issue/198874/11 "2025-01-29T18:08:20Z")
The BCM is the gate keeper that allows communication between other modules in the vehicle, This includes the engine control module, the transmission control module, etc… If the BCM is unable to allow modules to communicate with each other, all kinds of weird things can happen with the operation of the vehicle. Tester ---
**Author:** ![Mustangman](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/mustangman/32/44130_2.png) [@Mustangman](https://community.cartalk.com/u/Mustangman)\ **Post date:** [January 29, 2025, 6:23pm UTC](https://community.cartalk.com/t/help-me-with-engine-issue-cant-figure-out-the-electrical-issue/198874/12 "2025-01-29T18:23:09Z")
> [@Tacos1234](#): > > check engine light is on at it says its the catalytic converter I asked you to post the codes. Is the ONLY one you see is a P0420? Or are there more? We can’t help you if you don’t supply enough information. ALL of it. Not just bits and pieces. So I can’t answer your question unless I know what codes you are seeing. ---
**Author:** ![Tacos1234](https://avatars.discourse-cdn.com/v4/letter/t/22d042/32.png) [@Tacos1234](https://community.cartalk.com/u/Tacos1234)\ **Post date:** [January 29, 2025, 6:41pm UTC](https://community.cartalk.com/t/help-me-with-engine-issue-cant-figure-out-the-electrical-issue/198874/13 "2025-01-29T18:41:49Z")
My bad, P0420, P0725, P0868 ---
**Author:** ![Mustangman](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/mustangman/32/44130_2.png) [@Mustangman](https://community.cartalk.com/u/Mustangman)\ **Post date:** [January 29, 2025, 7:13pm UTC](https://community.cartalk.com/t/help-me-with-engine-issue-cant-figure-out-the-electrical-issue/198874/14 "2025-01-29T19:13:36Z")
OK, the catalytic convertor is bad, but you knew that. The P0868 is low fluid _ **pressure** _, not level. That would seem to indicate a failing pump. Inadequate pressure means the CVT belt slips. Since it is generally OK when cold…when the transmission fluid is thicker… the pump can keep up, more or less. When it heats up, the fluid is thinner, the pump has difficulty building pressure and the CVT belt slips making MORE heat and causing more problems. For sure change the fluid, it is way overdue. And then there is that P0725… This is an engine speed error code. The engine speed is the crankshaft position sensor (CPS). Apparently this is a common symptom of a failing CPS in a Nissan. They are cheap so I’d just replace it and see how the engine and transmission reacts. Given how poor these transmissions are, I’d suspect that is the bigger part of your problems. ---
**Author:** ![weekend-warrior](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/weekend-warrior/32/26122_2.png) [@weekend-warrior](https://community.cartalk.com/u/weekend-warrior)\ **Post date:** [January 29, 2025, 9:37pm UTC](https://community.cartalk.com/t/help-me-with-engine-issue-cant-figure-out-the-electrical-issue/198874/15 "2025-01-29T21:37:25Z")
A service bulletin I came across. when the fluid heats up above a certain temp threshold it goes into limp mode. It is probably why when the vehicle is cold it preforms better. when it heats up it goes into limp mode. A Continuously Variable Transmission (CVT) is designed to go into fluid temperature protection logic mode (“fail-safe mode”) if the CVT fluid temperature rises above a certain threshold. If the CVT goes into fail-safe mode, engine performance is reduced. Customers may report this condition as “low power” or “reduced engine performance” [Altima/Sentra/Rogue; CVT Fail-Safe Condition Service Information](https://static.nhtsa.gov/odi/tsbs/2016/SB-10091575-2280.pdf)