RizwanWali
TYF Newbie
So I have a ‘08 Yukon XL Denali (only 74k miles) which had a slight pulsing shakiness in idle like a misfire.
This is what I have done to try to smoothen the idle:
1. Ran a bottle of fuel system cleaner STP brand in the gas tank - no difference.
2. I thoroughly cleaned the intake and throttle body - no difference
3. Changed all spark plugs. Old ones were AC DELCO 41-993 and the new ones I installed were AC DELCO professional iridium 41-110.
I had the battery disconnected for 30 minutes and now idle has become more shaky than before. Also noticed a more pronounced jerk shifting from first into second. I drove it on the highway and did a few pulls but no difference.
Anyone have any idea what could be the problem here? What does the transmission have to do with the plugs? Did I use the wrong plugs?
This is what I have done to try to smoothen the idle:
1. Ran a bottle of fuel system cleaner STP brand in the gas tank - no difference.
2. I thoroughly cleaned the intake and throttle body - no difference
3. Changed all spark plugs. Old ones were AC DELCO 41-993 and the new ones I installed were AC DELCO professional iridium 41-110.
I had the battery disconnected for 30 minutes and now idle has become more shaky than before. Also noticed a more pronounced jerk shifting from first into second. I drove it on the highway and did a few pulls but no difference.
Anyone have any idea what could be the problem here? What does the transmission have to do with the plugs? Did I use the wrong plugs?