Fuel system running lean?

2006 MAZDA 3

300,000 MILES • 2.0L • 4 CYL • 2WD • MANUAL

ILVAGAMA

MEMBER
1 POST

Vehicle throwing code P2187 (System too lean at idle). I have replaced both o2 sensors, a new fuel filter, and run an injector cleaner through it, issue remains. Fuel trim (long term) is sitting around 20% and short term grows from 0 to 20% when at idle over approximately 5 minutes. While running, short term fuel trim varies between +8% and -8%. Hoping for suggested next steps in diagnosis before I shell out for new injectors, a new MAF sensor, new fuel pump, etc.

Mar 6, 2024 at 5:44 AM

STRAILER

✓ASE Certified Mechanic
54,832 POSTS

Yep, these are what is wrong typically when the engine is lean this guide can help you understand more on the problem, I can tell you if the power is okay and it starts up without cranking for an extended time I would replace the MAF sensor, this is a normal service item and if it is original at 300k it is a good bet, and if you get it from amazon you can send it back if it does not help the situation. Here is the location of the MAF sensor so you can swap it out. Check out the images (below). Please let us know what happens.

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Mar 6, 2024 at 10:59 AM

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