CEL and Trac off lights on!
Ok, so I just traded my 76 GMC Sierra for a 2001 Lexus IS300 literally 3 days ago, the previous owner has done a few mods, K&N cold air intake, bigger injectors, aftermarket headers and exhaust, was told he bypassed the heated throttle body? but I'm not sure. That's all I know of, not familiar with Lexus but hopefully you guys can help me with that.
I apologize for the long post, I just want to give everyone the info that I already have. I'm having a problem with "Limp mode", It intermittently goes in and out, having about 20-30% of throttle when in limp mode. I have heard the K&N are famous for causing MAF problems so that's where I started, cleaned the MAF and K&N air filter, made sure the throttle body and air intake piping were all clean. And still have the problem. It usually happens when I'm accelerating from a stop quickly, or I take a corner sharp and slow down rapidly, and I could usually turn the car off, take the key out, and restart it, and it would drive ok for about 10 minutes until I did one of the things above. But today, I did a few things, I reset the computer by just taking off the negative and positive and connecting them together to flash the computer(suggested by a friend) and while cold, I started it up and took it for a drive, accelerating and slowing down rapidly and It ran great, went faster then I ever have before in this car, but when I turned around in a parking lot, it popped the CEL and Trac off lights on and went into "limp mode". Tried my trick(turning it off and restarting) and it didn't work. I took it home let both of us cool down and came back a few hours later, reset the computer again, popped the radiator cap and let it idle until it got to running temp, the whole time it was idling no lights were on, but I was watching very closely and I believe I watched the thermostat open up and start circulating coolant and watched air bubbles rise to the surface, and then it started idling rough, I went to rev the motor to see if I could bring up the RPM and It was in limp mode again, having only about 20-30% movement in the throttle body and pedal, note all this was in my driveway, never driven, just idled until the thermostat opened.
So that brings me to my question, what could be my problem? Head Gasket? TPS? MAF? Throttle Body? Simple tune-up? Please help!
Last edited by HarleyCannon; 06-23-2014 at 01:32 AM.