[dgcarver]

Ever since I installed my Procharger D1SC on my 05 MN6 coupe, I have been experiencing a problem with the engine shutting down and the DIC reading “Reduced Engine Power” and “Service Active Handling” if it is not turned off. This seems to happen only when I begin reaching Boost levels around 2-3 psi (Maximum is 8psi). It does not do it every time, but most of the time.

Initially the first 2-3 times it happened I also got a check engine light. The codes were PO120, PO121, and/or PO122. Can’t remember which two of the three I had for sure. These were cleared by LG Motorsports Tuesday when they did the tune and also the first failure after I left their shop and returned. The check engine light has not occurred on the other 4-5 times it has failed since.

• PO120 is “Voltage is off for TP sensor 1”
• PO121 is “Predicated air flow and the predicated MAP combined are outside a calibrated range for more than 3 seconds”
• PO122 is “Throttle Position (TP) Sensor 1 circuit low voltage”

All of these are related to the throttle body.

Some other info:

• It never happened before I installed the Procharger
• It has happened in all four lower gears, only when going into boost.
• The engine sounds great until it happens and pulls very hard. After failing it goes into a very rough idle mode with hardly any response from the accelerator pedal. If you floor it, it might go to 1000 -1200 rpm. Not enough really to get it off the road!! By definition in the service manual, I guess this is “Forced Idle mode”.
• I have had one time that I ran it through the gears with no failure, taking each of the first three gears to maximum boost.
• When LG tuned it on the dyno, it never did it. They made several runs after final tune adjustments to 6500 rpm.
• I have driven it for about 400 miles since and if I keep it out of boost there is no problem.
• I tried turning off the active handling since I have been getting several “Service Active Handling” messages over the last several months. (These have only occurred when turning sharply at very slow speeds, mainly parking lots or turning around) At first, I made several spurts in the lower 4 gears and everything was working fine. Then a couple hours later, I tried it again and it failed the first time I went into boost.

Any ideas anyone? I really don’t want to take it to a dealer if I don’t have to. I’m hoping someone else has had this problem and can tell me what their solution was. Could it possibly be a loose connection? I already had one connector loose on my amp

 

[bigred vette]

call lg and try to reproduce it for them they should fix the problem if it never happened before.........its the first problem ive heard of come out of lg

 

[dgcarver]

I'm pretty sure it is not a problem caused by LG and did not intend to insinuate that it was. Shane (LG Tuner) worked with me to help figure it out when it happened after I left their shop. It had also failed prior to going to LG. Why it didn't do it during the Dyno tune, I don't know?? It might be because the dyno is done in 4th gear and the engine speed ramps up slower than the lower gears.

Today I am going to go unplug the connectors for the ECU and throttle bottle and check them out. I may make a few more acceleration runs and record some data also.

 

[bigred vette]

well i hope you get your problem fixed:cheers: