I live in Colorado and with the recent drop in temperature I've noticed some turbo creep. While driving normally, say 40 MPH, and I increase the throttle to 40-50% or more, the turbo will spool very quickly - to the point where the boost pressure well exceeds the traditional engine RPMs (like I'm used to during the summer and fall) for about 2 seconds. Then the engine RPMs line up with the boost and things seem normal for a split second. Then the extra exhaust spins the turbo faster and - again - the process repeats itself until I shift.

Basically I'm thinking that under these conditions, there's much more air being pumped into the cylinders without the fuel, and thus the RPMs, matching up. This could lead to detonation, but my dealer mechanic tells me that the wastegate and computer management program should prevent this.

Their advice? Bring it back if the engine light activates. Sure, I'm under warranty, but this seems odd.

Anyone have similar experience or any suggestions?

 

man i ahve no idea waht you are referring to. Boost creap is basicly a situation where you nail the gas say in 4th or 5th gear and as ur boost peeks levels out you can watch your boost begin to increase from that point beyond the limit (level at which it settled) A boost spike is a momentary increase of boost that drops off directly after the increase. Boost spikes and boost creap are two different things. Spikes are usualy found between ships or hard WOT punchs on the gas at the correct rpm. Boost creap is typically noticed in the larger gears such as 4th and 5th. Lower gears are too short to notice.

 

Thanks for the post. Ya, I agree about the larger (4th and 5th) gears, but I've experienced it in 2nd and 3rd. And I'm not smokin somethin' here, either. The difference between summer/fall temperatures and boost characteristics and those during these cold temps are not just noticeable, they're substantially different.

Today, for example, during mid-day temps in the upper 30°s, the creep wasn't there at all. But driving home from work at night, that creep was back. I can't help but to back off the throttle when this happens - it's a little creepy (no pun intended).

 

cold air = more boost, how much boost are you getting? I would hit like 21 when I was stock but it would not "Creep up"and drop down to say 19ish

 

I'm all stock without a boost gauge, so I can't definitively say what the PSI is at. I'm 100% with you on the cold air = higher boost levels, but it's just so different. In the summer I had normal turbo lag; but now, there's no turbo lag at all - in fact, it's more like turbo-super-spool-up. It's so quick, the engine doesn't recognize it in time and the engine has a lag.

 

you HAVE to get a boost gauge before you start thinking you have boost creep because really you have no idea. And when it's cold it does feel like 30-40 more HP. This is my 2nd turbo car and that the best part is the cold air = different car. Get a boost gauge and I am willing to put $100.00 that you are not overboosting.

 

Chopdaddy, you need a boost gauge to know if you have boost creep or not. I have basically Buschur's stage 1 and I'm in Colorado and not seeing boost creep at all. I am not using my MBC right now because the weather is cold and with the MBC, it likes to spike. On my boost gauge, peak boost is 1.4bar then drops to 1.2bar. When I was stock I saw 1.3bar peak then drops to 1.2bar.

 

man 30 degrees vs 70 degrees or hotter is like two girls walking into a Bar... one is a 3 on a scale of 10 and the other is a 9... big difference... lol

 

I hear ya. But is this cause for concern; that's what I'm after. Can I trust the dealer mechanic and ignore the situation and just keep it WOT or should I back off?

 

Seriously, you have to get a boost gauge or it will be next to impossible to diagnose what is going on.

Sounds like you're not getting into danger zones though because you are not hitting the cuttoff or throwing the CEL for overboosting.

Jason