Need help with intermittent skip
Thread Starter
Instructor
Joined: Sep 2008
Posts: 233
Likes: 17
From: Macon GA
Need help with intermittent skip
Need some help with 2000 A4 coupe that has an intermittent skip sitting and idling or when traveling at low speeds (30 mph or less). The skip is at low engine speeds and goes away when under power or when at highway speeds. Sometimes it will misfire only once or twice in a 2 or 3 minute span and sometimes it will misfire several times back to back. The low speed skip is like one cylinder missed fired then back to normal. At highway speeds (65-75 mph) it is as steady as a rock and doesn’t miss a beat. When I go to WOT it doesn’t miss a beat and pulls hard until I back off.
I pulled the codes and got B2284 (Battery #2), U1064 (Loss of communications with BCM), U1096 (Loss of communications with ICM), & U1016 (Loss of communications with PCM). These are all “battery/electrical” related so I am in the process of checking all connections and grounds.
Any Ideas where else to look/check? The skip is intermittent and low speed only.
Thanks for the help.
I pulled the codes and got B2284 (Battery #2), U1064 (Loss of communications with BCM), U1096 (Loss of communications with ICM), & U1016 (Loss of communications with PCM). These are all “battery/electrical” related so I am in the process of checking all connections and grounds.
Any Ideas where else to look/check? The skip is intermittent and low speed only.
Thanks for the help.
Le Mans Master
Joined: Mar 2011
Posts: 6,835
Likes: 302
From: Columbia SC
When posting codes you should indicate if they are H or C or both. We also don't know how old those are since you didn't say when you last pulled codes.
Delete those codes and then drive until you have an issue again and pull the codes.
It is always good to pull codes BEFORE you turn the ignition OFF. You may need to reset any DIC messages that are there to access the codes.
Once the ignition is OFF then almost all codes will show as H.
Mr. Sam
Delete those codes and then drive until you have an issue again and pull the codes.
It is always good to pull codes BEFORE you turn the ignition OFF. You may need to reset any DIC messages that are there to access the codes.
Once the ignition is OFF then almost all codes will show as H.
Mr. Sam
Instructor
Joined: Jun 2015
Posts: 118
Likes: 8
Low RPM misses are "usually" caused by an ignition issue or a vacuum leak. All engines have misfires all the time, if you get a scanner it that has access to this info, you'll see. It's when you have too many misfires that the CEL will be triggered.
I'd check vacuum first, then plugs/wires.
I'd check vacuum first, then plugs/wires.
Thread Starter
Instructor
Joined: Sep 2008
Posts: 233
Likes: 17
From: Macon GA
Original codes were all “H” so I cleared them and started over.
When checking the battery (7 year old Red Top) I found some corrosion. Some but not a lot. I cleaned that checked all the grounds (what fun), cleared the codes and then drove the car about 40 miles. It ran perfect no skip, jerk, or hesitation. I then checked the codes and they were all back. Cleared them again and decided to just drive it to see what happens. I have been driving as my daily driver for the last two days with no problems and no codes. I am thoroughly baffled!
When checking the battery (7 year old Red Top) I found some corrosion. Some but not a lot. I cleaned that checked all the grounds (what fun), cleared the codes and then drove the car about 40 miles. It ran perfect no skip, jerk, or hesitation. I then checked the codes and they were all back. Cleared them again and decided to just drive it to see what happens. I have been driving as my daily driver for the last two days with no problems and no codes. I am thoroughly baffled!
