Hi everyone, I am a newby here and need some help with my SC400. During covid we were pretty much locked down and could not get out at all. As a result my SC400 sat for about a year and a half without running at all. Now that we can get out and about I started the car and am getting a check engine light (rough idle). After changing # 8 cylinder coil I am now getting a code P300. I want to change plugs but car only has 90K miles on it. Any suggestions on where I should be looking after letting vehicle set that long and what I might do to correct my problems? I think I can do the work but I could be chasing/pouring a lot of money into it, before I find that one thing that solves it all. I love the car, always been great, but covid has taken its toll.

Thanks.

Keith

 

With a misfire it’s always advisable to change ignition components. Did the car sit outside? The fuel could be another issue. I would start with draining the tank and add some fuel injector cleaner and go from there.

If you still have misfires then I’d do plugs, then coils if you can identify which cylinder has the miss.

Nick

 

Thank you for replying, I am doing plugs today. Hopefully, that will help, also doing fuel filter.

 

If the fuel is bad, a new filter won’t do much. I would endeavor to drain the tank. Good luck!

Nick

 

I did get new plugs and the filter put on. It seems to be running much better and no check engine light. New problem now is, I cannot get the fuel filter to stop leaking. I noticed that when the old one came off there seems to be a slight kink in the line from the fuel pump side. Perhaps if I loosen that one up and retighten it hopefully that will help. Any suggestions? Bye the way, I did not buy a Lexus fuel filter it is an NPN ProTune, I didn't have any trouble getting the fittings started by hand so I am sure they are not cross threaded. If the kink is causing the leak, does anyone know what the part number of that fuel line from the fuel pump is? How difficult will that be to change?

I am closer to having a decent running SC400 though.

Thanks.