I have a question for those who have spent a lot of miles behind a TGP. Have you had a lot of problems with the ignition system, namely the ignition module and coil packs? Or is it just me?
For the last 3+ years now I have exclusively driven two different TGPs. Both had ICM/coil pack issues when I bought them. I fixed both up fine and both have had issues with the new parts failing again a year or so later. In the past, the issue has been misfiring from one or two coils: misfiring when hot, misfiring under load, or misfiring all the time.
This latest issue was different though. The red car which got a brand new ACDelco ignition module and 3 new ACDelco coil packs a little over a year ago. Starting a couple weeks ago, it would run perfectly fine until about 50% throttle and higher, then it would very suddenly bog like mad. No misfire, but it would just have no power, the engine wouldn't want rev past ~3500rpm, and boost pressure would spike. It felt all the world like a weak spark issue sometimes called "spark blow-out." After confirming fuel pressure was good (~52psi under heavy boost), I threw on a set of the allegedly higher-power "blue-bottom" coil packs from a spare L32 I have in the garage. Sure enough the car pulls hard again and pulls hard all the way to redline.
I've owned a lot of GM 60V6 and 90V6 engines, and wrenched on hundreds more, and although I've seen plenty of coil packs and ignition modules fail here and there, I've never seen anything like the temperamental nature of the ignition system of my TGPs. And that makes me wonder if the stock system is rather weak for a boosted application (especially one making more boost than stock like my red car does) and the slightest decline in output leads to issues.
So I'm just curious to hear if other long-time TGP drivers are in the same boat. How has your car done?