integgy

Hello I have a problem with my sc300 5 speed it's keeps bucking and losing power. It happens randomly most of the time it would drive fine some times it would cut out when I go wot. But today it was cutting out really bad to the point where I can barely move I couldnt go over 2k rpm. I've done maintenance to it recently and thought it would fix the problem.

Things I've done
Tps sensor
Spark plugs
Cap and rotor
Spark plug wires
O2 sensor
Fuel filter
egr

Please help me out with some ideas or input

KingReyes

Catalytic converter plugged. Therefore builds up pressure back to the engine, that's why you can't go past 2k

Might be sensor related.

KahnBB6

iTrader: (5)

^^ That could be it. Hard to tell without physically removing one or both of the cats and inspecting them or unless your ECU throws a code.

If it turns out that is your problem, read through this thread since you're in California and I assume you have a Cali-Spec model. If you have a Federal model that was brought into California then your options are slightly different.

https://www.clublexus.com/forums/sc-...nia-legal.html

You've changed out most of the major sensors already. Still a possibility.

You might also check into your EGR system to see if it's become clogged in any of the passages or valve ports (not an easy task) but with the 2k rpm limiting symptom you describe I'd say the EGR system is a very low probability as a culprit. The catalytic convertor is what I'd check into first.

integgy

alright i have a new cat that i havent had time to install hopefully it fixes it. might chagne the maf to new if that well do any good?

integgy

thanks ill take a look at that. oh i forgot to add on the list ive change my egr as well.

KahnBB6

iTrader: (5)

You mean you had a new EGR valve installed? If so, did you have the pipe cleaned while that was out as well?