P1170 - solutions?
#1
#4
Could be bad O2 sensors, but it seems that more people fix this code by finding and repairing a vacuum leak or replacing the MAF. Cleaning the MAF sometimes works also. Other possibilities are cracks or leaks in the cats, or I read one post where the code was fixed after two clogged injectors were cleaned.
I'd start with the easy stuff. Confirm that there are no leaks at the cats. Swap the sensors from side to side and see if the code follows them. Pull the plugs and check to see if they are showing consistent coloration. Try doing a smoke test to look for leaks (there was a post not too long ago about doing this with a rubber glove and a cigar). If none of that works, try cleaning the MAF.
I'd start with the easy stuff. Confirm that there are no leaks at the cats. Swap the sensors from side to side and see if the code follows them. Pull the plugs and check to see if they are showing consistent coloration. Try doing a smoke test to look for leaks (there was a post not too long ago about doing this with a rubber glove and a cigar). If none of that works, try cleaning the MAF.
#5
1170 is a code for a slow O2 sensor. The system checks them in various ways. It also checks the cats by comparison on the up and down stream O2s, and if storage capacity of the cat is exhausted it throws a code 420 or 430. Since 1170 is detecting a slow repsonse in recognizing a rich shift (by more than 1 second), it (and plenty of other codes) can be "fooled" by things like vac leaks, etc. If you download the Bosch ECU manual they have a technical discussion of O2 monitoring, etc. Links below, sorry, my copy is about 4 meg, so had to break it up for posting.
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