Just completed a trip from San Diego to Las Vegas and back.
The trip there was fine, running 75 mph on cruise most of the way there with the AC on. Averaged 34.5 mpg in my Sonic RS 6 spd manual.
On the return we decided to drive through Death Valley, CA (experienced flash flooding, thunderstorms, rain, wind, blowing sand and dust, etc). I was in the 40 mpg+ range when we stopped at the visitor center (102 F outside) 119 miles from departing Las Vegas. Then heading North and west climbing out of the area towards Ridgecrest, CA I passed 4 Hyundais that were being tested (lightly disguised, all appearing to run a set speed/course). During this time we began a 9% grade climb from below sea level to approx 5400' elevation. I was running the torque app, and just prior to passing the 4 I briefly hit 17 psi boost using the push to pass button (trifecta). After which I stayed in the stock power setting during the duration of the climb. My water temp was 209 F prior to the climb, and during the climb reached a peak of 232 F (briefly, I turned off the AC, turned the heater on, temperature dropped to about 220 F, and stayed there until reaching the summit). Prior to the 220 F+ temp conditions I was running about 10 psi of boost (stock power setting), no knock retard, no missfires, nada. The car was solid. Shortly after I turned off the AC, the power dropped on the car somewhat (it was a STEEP climb going 55 mph).
After that climb I noticed the performance was down on the car, anything above 1/2 throttle the car was a complete dog. I tried the performance setting (push to pass Trifecta as I call it), nothing. No difference. Looking at the boost I was getting no more that 5.7, 5.8... with performance setting or eco-stock setting. Water temp was around 209-210 F... the car drove fine. Just no boost.
I continued on until our fuel stop as the car was fine 70-80 mph on the fwy through socal, just nothing over 6 psi (and the water temp dropped with the lower temperatures to about 200 F, but still no boost).
I figured I was having either a turbo wastegate issue, or was losing boost via leak somewhere.
I stopped and fueled up (414 miles, 11.64 gallons, net 35.56 mpg which was amazing considering the driving we did (lots of heat, AC most all of the time, plus some seriously steep grades Sonic climbed very well, though with less than 1/2 of the boost). After the 5 minute fuel stop, I immediately felt like the car had regained it's boost (thought I was on the performance tune, nope I was on the ecomony tune). I checked via torque and the car routinely hit 8-10 psi again stock just getting on the fwy. I selected the performance tune... 22.5 psi was back once again.
What happened? Did the car get pi##ed off at the high temp and wouldn't let more boost than 6 psi until after a restart? The car drove fine this morning to work, all the power (both stock and performance tune) was there like always.
Stumped.
The trip there was fine, running 75 mph on cruise most of the way there with the AC on. Averaged 34.5 mpg in my Sonic RS 6 spd manual.
On the return we decided to drive through Death Valley, CA (experienced flash flooding, thunderstorms, rain, wind, blowing sand and dust, etc). I was in the 40 mpg+ range when we stopped at the visitor center (102 F outside) 119 miles from departing Las Vegas. Then heading North and west climbing out of the area towards Ridgecrest, CA I passed 4 Hyundais that were being tested (lightly disguised, all appearing to run a set speed/course). During this time we began a 9% grade climb from below sea level to approx 5400' elevation. I was running the torque app, and just prior to passing the 4 I briefly hit 17 psi boost using the push to pass button (trifecta). After which I stayed in the stock power setting during the duration of the climb. My water temp was 209 F prior to the climb, and during the climb reached a peak of 232 F (briefly, I turned off the AC, turned the heater on, temperature dropped to about 220 F, and stayed there until reaching the summit). Prior to the 220 F+ temp conditions I was running about 10 psi of boost (stock power setting), no knock retard, no missfires, nada. The car was solid. Shortly after I turned off the AC, the power dropped on the car somewhat (it was a STEEP climb going 55 mph).
After that climb I noticed the performance was down on the car, anything above 1/2 throttle the car was a complete dog. I tried the performance setting (push to pass Trifecta as I call it), nothing. No difference. Looking at the boost I was getting no more that 5.7, 5.8... with performance setting or eco-stock setting. Water temp was around 209-210 F... the car drove fine. Just no boost.
I continued on until our fuel stop as the car was fine 70-80 mph on the fwy through socal, just nothing over 6 psi (and the water temp dropped with the lower temperatures to about 200 F, but still no boost).
I figured I was having either a turbo wastegate issue, or was losing boost via leak somewhere.
I stopped and fueled up (414 miles, 11.64 gallons, net 35.56 mpg which was amazing considering the driving we did (lots of heat, AC most all of the time, plus some seriously steep grades Sonic climbed very well, though with less than 1/2 of the boost). After the 5 minute fuel stop, I immediately felt like the car had regained it's boost (thought I was on the performance tune, nope I was on the ecomony tune). I checked via torque and the car routinely hit 8-10 psi again stock just getting on the fwy. I selected the performance tune... 22.5 psi was back once again.
What happened? Did the car get pi##ed off at the high temp and wouldn't let more boost than 6 psi until after a restart? The car drove fine this morning to work, all the power (both stock and performance tune) was there like always.
Stumped.
