2003 Chevrolet Silverado Codes P0300 and P1518

Argyel · 2021-09-01T17:56:25+00:00

Started with reduced power P0300 misfire problem and a freeze frame fuel trim bank 2 of -54% short term -25%. Check data streams and all was normal O2 sensors all normal so I erase codes and start again and get reduced power P1518. Don't know where to look!!

ASEMASTER6371

✓ASE Certified Mechanic
52,796 POSTS

Good morning,

What are the long-term trims for both banks while running? They are more important than the short-term trims.

I attached the flow chart for you below of the code with steps to follow. In most cases, it is the throttle body that is the issue for both complaints.

https://www.2carpros.com/articles/how-a-throttle-body-works

Roy

Images (Click to enlarge)

Professional Diagram for 2CarPros Members
Click here to log in and view diagram.

Sep 2, 2021 at 1:55 AM

ARGYEL

MEMBER
3 POSTS

Bank 1 was 0 and bank 2 was -1.9.

Sep 2, 2021 at 6:04 AM

ASEMASTER6371

✓ASE Certified Mechanic
52,796 POSTS

Those readings are correct.

Roy

Sep 3, 2021 at 3:12 AM

ARGYEL

MEMBER
3 POSTS

Did not address my overall problem!

Sep 3, 2021 at 5:51 AM

ASEMASTER6371

✓ASE Certified Mechanic
52,796 POSTS

What steps did you follow in the flow charts that I left? The flow chart was very specific in tests that needed to be done.

Roy

Sep 3, 2021 at 10:41 AM