salimshah

Yes, we know what you desire, the problem is sensor outputs go the computer. The program then decides what to do to the fuel, air, spark timing and transmission. The program is part of the microcode.
As you know there are hacks to provide signals to the ECU and that procedure is considered tampering with emission control and is illegal.

Salim

marcov

O.K. Thanks.
Is there a pin-out diagram available that shows all inputs to the ECU from all these sensors? I could then physically follow the circuit board tracks and see if I have a bad capacitor or diode, or something else. That would be great
Thanks Salim!

marcov

I'm now trying to replace Knock sensor "Cable", however the wires on the vehicle (1999 RX300) are going from the knock sensors into a big bundle(>1 inch). The cable I received has three connectors, 2 for the sensors and 1 on the other end at about 16". Is there a hidden connector in the bundle???

Nad1370

I dont know if you've done the work already but thats all you need.
The bigger connector on the harness connects to the main harness of the engine.
Make sure you feel/hear a click on the connectors as you install them.
Double/triple check it.
You dont want to take it apart again once everything is together if not installed correctly.
Since you have everything apart, check the WATER INLET HOUSING plate.
With high mileage vehicles, coolant leaks out in that area.

marcov

Did not replace the cable because Rock auto sent me a cable that had different connectors. looked at all their other Knock sensor cables and they all have the same (wrong) connectors.
Now I just stop, turn off the engine and start it up again and can travel (with overdrive) until I come to a complete stop again. It's a pain in the *** but the vehicle runs fine.......
I think I may need to change the ECU.......
Thanks for your interest in my post.

salimshah

Overdrive lock out is a protection and if you follow the thread, the lock-out will start happening sooner and more frequently. I drove with the scanner for a while to reset, but eventually gave up and did the repair. The wire to the harness was most beatup and it was visually evident that it must be replaced for me. Regrettably it is a lot of tearup to just replace the connector wire. Can't offer much advice other than just rollup the sleeves and buy all new set of gaskets and redo the work. When I preasessed the work, I made up my mind that I need to purchase all the items from the dealer with my vin number.

Salim

Nolan

My Lexus is doing the same thing no 4th gear should I just get a brand new ecm and just program it cuz I changed all the solenoids filter knockcencors ,o2 ,sparkplugs I never cleaned that ground or whatever's by the back tire, I got a mini vci techstream when my subscription expires it was only 2 day 1 can I still use the ob2 on it or is that expt to Thanx I like the car but might have to get rid of it and get a pony or something

salimshah

Welcome to ClubLexus.
Anything mechanical or biological can give you trouble.
Please make sure you have a fully charge battery and then connect OBDII reader and read off any ECU codes that are present. if there are more than 1, write them down and then clear codes and re-read on the onset of CEL. Then diagnose based on the code.

Salim

Margate330

Yes, need those codes.
Does the engine run well?

Nolan

The battery is good everything should be good should I just get a new ecm instead of a used 1 might b better and cheaper instead of going through all this stuff idk Thanx for all the replies

Nolan

What about resetting the ecm with the plug u plug your obd2 in .its number 13 and 4 I believe put a wire in there for 30 mins does that work or what it's supposed to clear the computer or reset it I don't want to short nothing out

salimshah

Keep in mind the ECM will have to be programmed to your key(s).

Have not heard about the error codes. Don't be tempted to clear the codes. Read them and note them and then clear. Disconnecting the battery for about 20 mins will clear the codes too.

Salim