Good point! Gaskets have been ordered!

 

Thanks for the DIY Salim! Knock sensors have been successfully replaced! Everything went very smoothly and RX is running great, ready for another 240,000 miles!

 

Glad things went well.

I just wish there was a tunnel to get to the knock sensors. Did you replace the bypass hose or just pushed it aside?

Salim

 

Hyper, well done my friend!

 

Thanks!

Yeah, a tunnel would be nice! haha. I didn't replace it, mine was also in good shape by the looks of it so I just pushed it aside.

 

I have a 2003 Lexus GX 470 with a V8 engine and need to replace knock sensors. Is this close to the same steps I need to replace mine.

 

Best to ask the same question on GX forum and point back to this thread.

I would say other than in the things being same in 'theory' we are talking about different engine here .. traverse mounted v6 vs front-to-back V8.

Salim

 

2000 RX300 with 275K miles

I have the dreaded P0330 knock sensor circuit 2 problem.

I followed this great tutorial and I replaced both sensors, along with the wire and gaskets over the weekend. Well, after 50 miles of CEL-free driving the code decided to come back. I am absolutely stumped as to how I could have solved the problem, but it then came back 50 miles later. Now the CEL comes on every couple miles after you clear it. I have a ScanGauge II which is a great OBDII reader, reads and clears CEL but has other info like freeze frame info when a code gets thrown. I can post that stuff here if it's useful.

Also, water leak started around same time in the cabin, definitely radiator fluid, smells like it anyway, could it be the heater core? Could this cause CEL?

Car also had P0171 and the other MAFS code I forget what it is but I solved those by cleaning the MAFS with a spray bottle of MAFS cleaner... P0171 went out at the same time. I did all that maybe 100 miles before I did the knock sensor replacement.

 

could you elaborate on where the wires go and how hard are they to change

 

Knock sensors are screwed into the engine block. The 'wire' connects the sensors to the wiring harness.

Since the teardown is huge, I would replace the sensors and the wire, even if only one parts has gone bad.

Salim

 

OK so my Lexus is not showing in to overdrive I've read about it being a couple things ones the solenoid in the trans and the seconds the knock sensor I've ran the cods on it and only cod I'm going is and has Ben a o2 sensor and it's Ben bad for a couple years now any suggestions

 

Knock sensor will light up your cell with the code for knock sensor.
Did you clear the codes [O2] and did you get the OD back?

Salim

 

yes it has batts Ben unhooked parts store cleared the code and all no knock road has ever shown up but I'll tell u wat soon as I leave work I'll have it done again and let u know and the o2 is a ever since I got the truck 2 plus years ago the not shifting is since just this past spring

OK update just had it looked at again and it's saying both r bad so I guess I'm in for a job soon to guys for the help

 

This is what I have for parts so far. These are for the 2002 RX300, I know the older and maybe newer 1st gen might have different part numbers and even knock sensor size.

So here is my list for replacements:

(2) Knock Sensors: 89615-12090
(1) Sensor Wire: 82219-07010
(1) Bypass Hose: 16261-20010
(2) Hose Clamps: 90467-28007
(1) Surge Tank Gasket: 17176-62030
(1) Passenger Right Intake Manifold Gasket: 17177-20020
(1) Driver Left Intake Manifold Gasket: 17178-20020

The spark plugs aren't that hard to get to, so I'm leaving them off the list.

Does this look right?

 

RX300 2000 I have p0330 planning to get knock sensor and harness replaced. My timing belt and water pump is also due. Do you think its a good idea to do it at the same time to save some money and what about by pass hose change?