I had a pretty alarming highway merge experience yesterday, and I was wondering if anyone else has experienced it. I can't seem to reproduce it, so I'm sure Mitsubishi would just tell me to get lost if I took it in.

I was accelerating lightly in 4th as I approached highway speed. Traffic was heavy, and I had to brake somewhat to find a gap. As I was doing so, I rev-matched a downshift into third.

I went WOT to get back up to speed, and that's when the issue occurred... It would cycle back and forth between what I know WOT should feel like, and something that felt like 50% throttle. It cycled between these two a few times a second, over and over until I let off the throttle. I did not notice any burnt clutch smell, and in any case the shift was fully executed by the time I got back on the throttle.

I got no check engine light, and I haven't been able to reproduce it since. I have the first reflash, but not the second. That's my only real guess as to what is wrong, so I'm supposed to get the 2nd flash next week. I've heard a high-RPM stutter described here before, but it did not sound this violent.

 

I would take it to mitu, and see what they think... that is if it is under warrenty

 

it's completely stock, so it'd be covered... the problem is I haven't been able to reproduce it. I guess it was a fluke. Even if I took it to the dealership, they go out and drive it, say "it seems fine to us" and be done with it.

I've been keeping an eye on it, though.

 

Err aren't you talking about when you lift the throttle for a sec at mid-high rpm then if you try to go full WOT again, the car would buck like crazy? Isn't that common on turbo cars?

 

It's been several weeks now, so my memory's hazy on the exact circumstances, but that could have been what happened. Bucking is a good way to describe it. I've tried to reproduce it and failed, but I may have been doing something differently.

This is the only turbocharged car I've ever had, so I wouldn't be surprised to learn it was a common characteristic that I had simply not encountered before. What is the reasoning for this? Some kind of compressor surge?

 

I had this same problem with my old srt-4. turned out to be bad plug wires. May want to check the the coils (since there are no plug wires) also check if the plugs are fouled from the pig rich a/f mixture.

 

shouldn't be fouled if the cars stock.
but still check them.

 

High RPM driving has been fine since. Could a fouled plug cause problems only under certain conditions? It seems to me that the performance would be bad all the time.

Still, it's easy to do. I'll take a look.