So Iast week my RX300 starts misfiring while driving. The check engine light was flashing on and off so I drove it home immediately. I switched out the ignition coils and spark plugs as well as valve cover gaskets as they were leaking. I put everything back together and same issue. The RX won't hold idle. It's very jumpy and keeps shutting off. I also smell gas. I tried starting it again and it won't crank or try to turn over. When I turn the key the engine goes" clock" once and that's it. It's similar to when a starter goes bad but I'm pretty sure that may not be it. The sound comes from the engine wanting to turn over. The battery is also fine and charged up. Some one told me maybe the throttle position sensor is bad. I took off the throttle body, cleaned it best a I can with throttle cleaner. I put a new TPS on and cleaned the MAF sensor. I know the MAF sensor works because that was the first test done the first time around was unplugging it while the engine was running jumpy and it got worse. There was a significant idling difference. I'm lost
Any help on this is appreciated as I do not want to spend money getting it towed and repaired by a mechanic as that can be rather costly. Maybe I can get help to figure this out. Please help!

 

Lets start by taking the first right step. Lets leave the engine running out of the picture for a bit.

Starter: It seems it is not able to turn the engine.
Engine binding -hydro-lock (unlikley) but the chamber can have fuel ... take the plugs out and then try to crank.
battery-clamps-cable-ground .. Verify and reverify. Try getting a jump start.

Once the engine is cranking [wether it catches or not] we will dig into other things.

Please list codes once you get past the starter issue.

Caution:
Beware of advice over the net or even from a well meaning friend. The burden is on you to discard the chaff. Early model RX are cable connected to the throttle. TPS is for kick-down. In any case the throttle has very little to do with starter cranking full speed or not.

If you removed some grounds .. please make sure they are back in place.

Salim

 

So I just noticed that the battery was the issue. I jumped it and it started. However now there is a knocking noise and unstable idle. I switched it off to prevent damage. I also noticed that the PCV valve was very brittle and shaking. I have a new one as well as a Dorman rubber grommet for it. I installed the grommet but the new sensor is a pain in the a$$ to put in. I will try again later once the sun goes away. I wonder if the knocking is the knock sensor?

 

now its time for the codes.

Salim

 

Working on getting a scanner. Will post the codes soon. Thanks for assisting .

 

light coating of liquid soap will help.

Salim

 

Okay I tried light coat of engine oil and it didn't help getting the PCV valve in. There is a small vacuum apparatus right over it that is blocking access. I will try the soap as you suggested tomorrow.

 

Are you sure you are trying to install the correct version of the PCV? Lexus went from a friction fit to a screw in at some point, and if your rear valve cover has been changed it may be different from what it once was.

 

The one I removed was a 90 degree plastic non screw in type that you need to push in. I got exactly the same thing that I took out. Purolator PCV valve and Dorman grommet.

 

Here are the codes,
-P0302
-P0301
-P0300
-P1325
-P1315
-P1310
-P1305
-P1300
-P1320

 

Can you clear and reread.

Check your grounds between the firewall and the head. Most likely you forget to connect one or more. There is also a ground that runs near the dog-bone.

Salim

 

Ok so this wire circled in blue apparently is disconnected. Please see attached image. I see the black insulation sticking out from harness with barely any wire attached to it. Must have ripped off and missed it when I was removing the intake. That being said the ground should still be bolted to the throttle but wire ripped out. This you are saying can cause an issue? I can try to rejoin this wiring im hoping with a piece of automotive ground wire without removing the entire throttle and intake.......

 

That is a googled image by the way. Was trying to recall the connections in the back of the engine.

 

I am going by memory and there are more than 1 wire [2 or 3].

You may have to solders a bit of wire to extend the cutoff piece. Make sure you use the right spot on the head to make the connections and make sure you dont have wire length more than needed. Just enough to reach and have a bit of slack for motor to move.

If you want to make more room, you can take off the cowl [will need to remove the wiper motor]

Salim

 

Yes there are three. Two black wires with interconnections that jack into each other. Those two are connected. The one that ripped off is the only one I see to connect. I will be sure to let u know how it goes. Thanks again!