Tartar

My son brought his 1997 Lexus ES300 home yesterday chugging along with a really rough idle. I hooked it up to my generic OBD2 scanner and retrieved these initial engine codes.


So I disconnected the battery's negative terminal for a minute or so to let the ECM reboot. I drove it around the neighborhood and came back with these codes which are mainly the multiple misfires.


Could it be that all three Oxygen Sensors are bad or some other faulty part could have caused these engine codes like a bad ECT sensor? Any input would be greatly appreciated.

Thanks!

PFB

Start by measuring your battery voltage and charging system. You could have a low voltage issue

HomerJay

Also, read this thread and search the forum for more info;
https://www.clublexus.com/forums/es-...e-problem.html

Tartar

Thanks for your help, guys. I'll tackle this problem starting tomorrow when I get off work. I plan on checking the ignition coils and spark plugs first to eliminate the "spark factor. Check and clean the MAF sensor. Then check the fuel injector valve for fuel pressure.

If all those systems pass, I will look into the EGR and OCV. Wish me luck!

PFB

Before you jump, to time consuming diagnostics, follow my simple suggestion to you. And check your battery and voltages. If that’s not it, than you can look elsewhere.

Tartar

I will. Thank you for your suggestion!

Tartar

The car is fixed and running like a champ! I checked the battery's voltage (12.9) and made sure that no power drain was going on by measuring battery to ground amperage (1.0). I checked all the fuel injectors using the "listening with a long screwdriver" method. They were all ticking as they should. I had suspected that spark was the problem when multiple cylinders misfires kept coming back after I'd erase the engine codes. I guess that the Oxygen Sensor codes (P0130, P0133, P0150, P0153, and P0420) were all just a result of the cylinders misfiring.

I dreaded changing the three spark plugs in the rear since I still remember what a PITA it was to change on my 1999 ES300. Yep. It was just as painful this time with my son's car, but nothing good comes easy in life. I'm just ecstatic that he got his car back and I continue to look like a "car" idiot savant to him.

Thanks for everyone who tried to help out! I hope this thread helps someone else with their car problems.