On the commute home today, my 1.8t tiptronic with 60,000 miles started 'bucking'. The check engine light never came on. I was in stop and go traffic on the freeway. I immediately turned off the air cond to reduce the load as much as possible. It continued to do this more often than every minute or two. It never died, but when it was doing it I couldn't accelerate; the car would coast down. I had a chance to go 40+ mph, and opportunity to raise the rpm to 2,000+, but it did the same thing. When I stopped and had it in park, it would idle, then the rpm would go up a bit and light black smoke would come out, then the idle would drop below normal for a couple seconds. Then it would idle regular for 20 seconds and do it again.
On the phone the dealer thought bad gas since no codes were ever shown. Amoco says they test there gas every day and haven't had any water in it. They also said the delivery had last been a couple days ago.
I did put a full does of Amsoil PI (injector cleaner) in with the fill. I do this every few months. Could it cause vapor lock?
What other issues may be the culprit and how would I test for them? Thanks for your ideas.
On the phone the dealer thought bad gas since no codes were ever shown. Amoco says they test there gas every day and haven't had any water in it. They also said the delivery had last been a couple days ago.
I did put a full does of Amsoil PI (injector cleaner) in with the fill. I do this every few months. Could it cause vapor lock?
What other issues may be the culprit and how would I test for them? Thanks for your ideas.
