On my 2000 XK8 I keep getting code 171. Now trying "seafoam" injection cleaner, didn't want to wait for "bg 44k". Also while driving, get res. perf.
for abt. 20 seconds then goes away. Charged batt. to 12.8 v. Idle it's 13.4 and alternator reads 14.25. Cleaned mafs. Whats next? I would really like to cure the code 171.

 

OBD code 171 is lean right side. Usually it has its brother 174 along with it, left side.

Thoughts:

Clean the part load breather tube.

Look for air leaks in the air filter to throttle body duct work. Small leak may only be enough to trip one sensor.

Swap the up stream O2 sensor leads where they connect to the harness at the firewall. If the problem becomes 174 then there is an O2 sensor or related wiring issue.

 

The work according to GUS.




http://www.jagrepair.com/images/Auto...7_ECM_2000.pdf


Wayne

 

Remember that the P0171 code is only one side as Tom indicated so the things to check are narrowed down. A misfire that could be related to fuel presentation (injector) and/or exhaust leak. I would recommend using BG44K and see what takes place. Keep in mind that BG44K is used by Jaguar and other dealerships along with above average repair shops you will not find it at most auto parts stores.