Hi all -
I'm the original owner of a 2002 P5 with 208k on the clock. I posted recently about a rough idle that I believe was due to carbon buildup on the EGR, but got no responses.
To address what I believed to be EGR build-up, I started driving the P5 on longer trips, more open throttle and stopped just letting it idle to warm up once a week if I didn't need to drive it at all. That issue got waaaay better, so I feel like maybe I was onto something with the EGR because usually car problems don't get better. I now have much better idling and she runs through the rev range nicely, no skips, stutters, etc. with an exception: yesterday I was driving on the freeway at about 70MPH in 5th - normal stuff - and her motor's skipping a little, a little stutter but it didn't do it again the rest of the drive and at similar, sustained speeds on boulevards.
Is this a misfire, and if so, why never on run ups through the gears and why so intermittent? Something else entirely? Bad gas?
I am going to go to O'Reilly's and ask them to scan for codes and also fill up with new gas. She was on a lifetime diet of 91 Octane (generally Chevron, Valero or ExxonMobil) but I did go down to 89 to save a couple bucks, so there's that but I can't imagine the motor's tolerances are that fine.
Any thoughts on the potential cause are welcome.
Thanks!
I'm the original owner of a 2002 P5 with 208k on the clock. I posted recently about a rough idle that I believe was due to carbon buildup on the EGR, but got no responses.
To address what I believed to be EGR build-up, I started driving the P5 on longer trips, more open throttle and stopped just letting it idle to warm up once a week if I didn't need to drive it at all. That issue got waaaay better, so I feel like maybe I was onto something with the EGR because usually car problems don't get better. I now have much better idling and she runs through the rev range nicely, no skips, stutters, etc. with an exception: yesterday I was driving on the freeway at about 70MPH in 5th - normal stuff - and her motor's skipping a little, a little stutter but it didn't do it again the rest of the drive and at similar, sustained speeds on boulevards.
Is this a misfire, and if so, why never on run ups through the gears and why so intermittent? Something else entirely? Bad gas?
I am going to go to O'Reilly's and ask them to scan for codes and also fill up with new gas. She was on a lifetime diet of 91 Octane (generally Chevron, Valero or ExxonMobil) but I did go down to 89 to save a couple bucks, so there's that but I can't imagine the motor's tolerances are that fine.
Any thoughts on the potential cause are welcome.
Thanks!
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