Hi,

I have a 1997 Mazda Protege LX. The check engine light has been on for some time so I used an OBD II scanner on it to see what was going on.

I checked it for the first time mid Jan. 1/15. P0170 came on. I erased that and 3 days later the engine light came on again. Checked again and still reads P0170.

P0170 reads Fuel Trim Malfunction / Bank 1 and after googling around I couldn't learn much more about the issue. Can anyone shed some additional light on this? Should I be concerned or should a professional look at this for me?

Thanks for any advice.

 

This DTC usually means a lean condition. First I would check to make sure there are no leaks or cracks in the air intake tubes. The next possibility is a partially clogged fuel or air filter. Here are some attachments with more info on the code.

[IMG]local://upfiles/1828/B09D7DD44155438EAAE4A29B67CDCD9C.jpg[/IMG]

[IMG]local://upfiles/1828/16130290A46843B9AAC7DBED38F29EC7.jpg[/IMG]

 

very good advice...could be a intake manifold leak...ive seen this before for protege

 

Thanks for the info. The emissions dept didn't like what they got back from their OBD scan on this...failed the OBD results. So i'm off to my mechanic to see what the fixes might cost to get this a passing grade.

 

P0170 only indicates a fuel trim malfunction but does not give a clue to if is a lean or rich limit reached. Freeze frame data would give that information but you were maybe unable to retrieve that info with a scanner. Vacuum leaks at the intake are a little common on the 1.8l engine but less so by far on the 1.5l. Mass air flow sensor has been a much larger culprit of this code being repeated over and again with no other problems found.

 

AGREED!

 

can u use brake cleaner around the suspected areas of vacuum leaks to see if the motor revs up? therefore locating the leak?