#RoughIdle

Steven writes:

Hi Sajeev,

I have a 2016 Hyundai Tucson 1.6T with 90K and I have an intermittent issue of a rough idle with the A/C on — it feels very jumpy and did not have this issue before. When you turn it back off the idle becomes smooth again. I’ve cleaned the MAP and boost pressure sensors as well as removed the throttle body to clean it — it had a little gunk at the bottom of it but it looked really clean. That seemed to clear up the problem, but the issue came back again. I know it’s due for another spark plug change (as Hyundai says every 45K) so I’ll get that done soon. but I’d like to trace this down while I’m doing the work under there.

Any ideas?

PS: And no, it’s not under warranty — as countless others have claimed.

TTAC commentator Jerszy writes:

Dear Sajeev;

Hopefully you & your fantastic community can help me here.

I recently purchased a 2002 Dodge Dakota Sport 4X4 (3.9 V6, 67k, Auto).

I bought it to replace my 2002 Cougar Sport Package (2.5 V6, 64K, Manual, speed-limited to 139mph) which as you know is not a good suburban truck and can’t really haul things. The Cougar was a fun car, very agile and could haul me around town and being a kitty-car it really did purr. Unfortunately it had to live outside in the rusty north for the last 6 years and was starting to age rapidly. Since I live in a “snow belt” (avg. snowfall ~120 inches a year) it had to be 4 wheel drive.

Now the Dakota is a definitely a truck. Almost as big as the ‘76 Silverado I had 30 years ago and just as four-wheelie as the ‘84 Toyota 4X4 truck I replaced it with. (That Toyota rusted, rusted, rusted so much I had to fabricate a wooden bed for it in 1987!)