ishootstuf

iTrader: (1)

UPDATE: I replaced the Bosch platinums with NGK copper plugs and the problem is gone AND so is the rough idle. I really REALLY thought the roughness was mechanical. It didn't sputter or idle irregular, just rough.

I knew Bosch Platinums sucked, but I had no idea how bad. I just put those plugs in a year ago when I was NA because it was the only plug the parts store had. Lesson learned. Still don't understand why I didn't have a rough idle prior to going turbo though.

Re-edit... It WAS mechanical. A brass fitting off the wastegate was hitting the crossmember. Not sure why I'm editing this... it's like I'm talking to myself.

Car had been running fine for a month or so, then I finally got around to degreasing the engine. I made the mistake of putting aftermarket plug wires on and the tubes the spark plugs sit in FILLED with water. The car wouldn't start. I pulled the plug wires and blew out the tubes with compressed air for about an hour. It sucked... I got the car started and it ran horrible. I drove it around for about an hour in the southern AZ heat and it began to run OK again - except when I hit max boost which is 9 PSI. At that point, it sputters and backfires. A/F is around 10 at the time so I'm not going lean. I didn't change the tune at all after the degreasing. I thought maybe I filled a cat with fuel so I tried running it straight out of the downpipe and it ran WORSE. Its been a week and I have driven it about 100 miles in 100 degree temps. It's dry everywhere I can see. I have checked the vacuum lines and electrical plugs, all OK.

Where do I start?

Unrelated to this issue... I have had a rough idle ever since going NA-T. It's not a misfire or tune issue, it's mechanical. Motor mounts are tight, exhaust is not hitting anything, intercooler piping is not hitting anything.

Any suggestions?

Here's a link to my build...
http://home.comcast.net/~ishootstuff/lexus/index.htm