Check engine light turned on and the rpm's will not go over 3,000

2009 VOLKSWAGEN JETTA

42,700 MILES • 5 CYL • AUTOMATIC

KASEYLWILTON

MEMBER
1 POST

My boyfriend just bought this car used from a dealership 2 weeks ago and it has been working in amazing condition, except today as he was driving in the rain for work. the check engine light came on, and the rpm's will not go over 3,000. Any ideas as to what could be wrong?

Oct 16, 2014 at 6:03 AM

RASMATAZ

✓Experienced Mechanic
75,992 POSTS

First step is to have the computer scanned for code.

go to this link:

https://www.2carpros.com/articles/checking-a-service-engine-soon-or-check-engine-light-on-or-flashing

Oct 16, 2014 at 6:23 AM

F4I_GUY

✓Experienced Mechanic
3,302 POSTS

You have a 2.5L 5 cylinder I'm assuming? The ECM most likely has a fault for one or two knock sensors which will throw the ECM into limp mode, which means it will limit it's RPM. Replace the affected sensors and clear the fault. It will be good to go!

Dec 3, 2014 at 9:12 PM

ASEMASTER6371

✓Experienced Mechanic
52,796 POSTS

Good evening,

There is a fault code stored in the ECM and that will help us narrow the area of failure. Once we know that code, we can help you determine the root cause of the failure. A parts store will read the codes for you for free.

https://www.2carpros.com/articles/reduced-power-limp-mode

https://www.2carpros.com/articles/checking-a-service-engine-soon-or-check-engine-light-on-or-flashing

As far as the limiting, that is the ECM. It is doing this so you can continue to drive the car until repairs are made. Once the code is diagnosed and repair, it will go back to normal.

https://www.2carpros.com/articles/engine-has-low-power-output

Roy

Apr 17, 2020 at 9:10 AM

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