On my way into work today, I jumped on the highway (no one really around), and punched it through 2nd and into 3rd gear. As I was nearing the last 1000 rpms or so of 3rd, the car was boosting 1.1 steady then dropped to .9 (felt the difference in pull too) and then climbed back up within a few hundred rpms to 1.1. I shifted into 4th, and the car stayed at a steady 1.1 with no hiccups...then decided to slow down since the exit was near.

My question then, is this a sign of a boost leak, bad plugs, or maybe just a fluke? It was a very evident feel, but didn't "hiccup" like when I had the old FR5 plugs. Thanks for any thoughts or insight.

 

bong - what did the hicup feel like?

 

Hey Chris, it really was not a hiccup, more of a flat spot feeling, like I released the pedal a little and depressed it again.

 

seems like ur pulling timing and or the TB is shutting down.

 

Hey Markski, I think you are right about it pulling timing. As for the TB shutdown, it is not going into limp mode at all. I will try to do duplicate it again tonight on the way home.

Thanks.

 

following

 

My car was doing that in all gears. Boost would drop in the midrange, then pick up as I neared redline. Replaced my plugs - problem solved.

 

Yup.... problem described above is ignition related not boost leak related.

This is what you get with a true boost leak:

 

 

Definitely in "Limp Mode"