High, I need help with my 2004 BEW engine (5 speed manual).
253,000 miles
Changed the MAF sensor (Bosch 0 281 002 531) to cure a loss of speed going
up a hill with the cruise control engaged. This problem was solved. The
throttle response was definitely improved. The car felt good. After driving
the car 15 minutes the CEL came on. P2196, O2 sensor stuck/biased high (rich).
Repeatedly cleared the CEL and it kept coming back.
253,995 miles
Changed the O2 sensor ( Bosch 17480 ). Cleared the CEL and got the car
successfully through emissions. The CEL came back after only about 150 miles
of driving.
Checked the following:
Using my OBD scan tool I examined the real time O2 sensor output. At idle,
fully warmed up, I was getting 1.24V to 1.27V. The signal should be
switching between low (less than 0.5V) and high (greater than 0.5V).
Removed the EGR valve and discovered that it was completely gummed up with a
black sooty sludge. Cleaned the EGR valve, and reinstalled it. The intake
manifold, and pipe from the EGR cooler did not appear to be obstructed (at least what was visible).
Cleared the Cel and it came back on almost immediately.
In one of the forum postings found that it is common to have a leak on the
output barb of the vacuum pump. Mine was loose, so it was repaired with epoxy.
The the throttle response improved noticeably. Also the brake action was more positive.
Using a Mityvac I tested all of the all of the vacuum actuators. All of them
held a vacuum, and seemed to be moving correctly. No leaks could be detected
on the hoses or check valves.
Replaced the EGR valve at 256,000 miles, and cleared the CEL. It came back
on after 30 miles ( P2196 ). At this point in time the car starts instantly,
idles smoothly, and has excellent throttle response. Under a load the engine builds RPMs
just like it was a new vehicle. With mixed driving I am getting 43 miles per gallon.
Does anyone have an idea about what my root problem could be ?
Thank you for your help.
253,000 miles
Changed the MAF sensor (Bosch 0 281 002 531) to cure a loss of speed going
up a hill with the cruise control engaged. This problem was solved. The
throttle response was definitely improved. The car felt good. After driving
the car 15 minutes the CEL came on. P2196, O2 sensor stuck/biased high (rich).
Repeatedly cleared the CEL and it kept coming back.
253,995 miles
Changed the O2 sensor ( Bosch 17480 ). Cleared the CEL and got the car
successfully through emissions. The CEL came back after only about 150 miles
of driving.
Checked the following:
Using my OBD scan tool I examined the real time O2 sensor output. At idle,
fully warmed up, I was getting 1.24V to 1.27V. The signal should be
switching between low (less than 0.5V) and high (greater than 0.5V).
Removed the EGR valve and discovered that it was completely gummed up with a
black sooty sludge. Cleaned the EGR valve, and reinstalled it. The intake
manifold, and pipe from the EGR cooler did not appear to be obstructed (at least what was visible).
Cleared the Cel and it came back on almost immediately.
In one of the forum postings found that it is common to have a leak on the
output barb of the vacuum pump. Mine was loose, so it was repaired with epoxy.
The the throttle response improved noticeably. Also the brake action was more positive.
Using a Mityvac I tested all of the all of the vacuum actuators. All of them
held a vacuum, and seemed to be moving correctly. No leaks could be detected
on the hoses or check valves.
Replaced the EGR valve at 256,000 miles, and cleared the CEL. It came back
on after 30 miles ( P2196 ). At this point in time the car starts instantly,
idles smoothly, and has excellent throttle response. Under a load the engine builds RPMs
just like it was a new vehicle. With mixed driving I am getting 43 miles per gallon.
Does anyone have an idea about what my root problem could be ?
Thank you for your help.