Knock Sensor replacement
Thread Starter
Rookie
Joined: Nov 2017
Posts: 89
Likes: 7
From: Georgia
Knock Sensor replacement
Hey everybody
I've got a P0325 code and have been experiencing loss of power/hesitation from the car. I'm getting ready to order all the parts needed and do the job myself. I've found a few threads on here where others have experienced the same issue. I just wanted to see if anyone could confirm that I won't need any other parts than the ones I'm planning on ordering. As well as see if any has a few tips on getting the job done. I've found the service manual directions for getting to the sensors and plan on using it as my guide. I saw someone mention that it'd be a good idea to service the fuel rail/injector seals at the same time. Anyone got an opinion on whether that's a good idea or a job that I can hold off on? Or if there's any others that should also be done at the same time? If the fuel rain/injector seals should be done at the same time what parts do I need to look at? Here's the parts I'll be ordering thanks in advance for any help!
TOYOTA / Lexus -Engine Intake Manifold Gasket Part # 17171-50020
Toyota/ Lexus Throttle Body-Gasket Part# 22271-50042
Toyota / Lexus Knock Sensor replacement Part # 89615-30080
Wiring harness 82122-50060
I've got a P0325 code and have been experiencing loss of power/hesitation from the car. I'm getting ready to order all the parts needed and do the job myself. I've found a few threads on here where others have experienced the same issue. I just wanted to see if anyone could confirm that I won't need any other parts than the ones I'm planning on ordering. As well as see if any has a few tips on getting the job done. I've found the service manual directions for getting to the sensors and plan on using it as my guide. I saw someone mention that it'd be a good idea to service the fuel rail/injector seals at the same time. Anyone got an opinion on whether that's a good idea or a job that I can hold off on? Or if there's any others that should also be done at the same time? If the fuel rain/injector seals should be done at the same time what parts do I need to look at? Here's the parts I'll be ordering thanks in advance for any help!
TOYOTA / Lexus -Engine Intake Manifold Gasket Part # 17171-50020
Toyota/ Lexus Throttle Body-Gasket Part# 22271-50042
Toyota / Lexus Knock Sensor replacement Part # 89615-30080
Wiring harness 82122-50060
Last edited by SlkySmooth; May 17, 2018 at 06:42 PM.
Instructor
Joined: Dec 2015
Posts: 878
Likes: 232
From: Arizona
You can leave the injectors, fuel rail and throttle body attached to the manifold when you remove it if you don't want to service them. Each injector takes 2 o-rings and one rubber gasket. Keep track of where the injectors go if you remove them as the 4 rear ones have different part numbers and have a little insulating sleeve that goes over them that can be reused. You will also want to get new crush washers for the pulsation dampers as they are removed with the fuel rail. When I pulled my intake my injector seals were crispy with only 114k miles.
CL Community Team
Joined: Feb 2013
Posts: 2,501
Likes: 245
From: Milwaukee, Wi
I would think about the starter while I'm that deep into the engine....
And FYI...
And FYI...
- Install the upper and lower intake manifolds assembly with the 6 bolts and 4 nuts.
Last edited by 2KHarrier; May 18, 2018 at 09:01 AM.
Instructor
Joined: Dec 2015
Posts: 878
Likes: 232
From: Arizona
I wouldn't mess with the starter unless there is a problem with it. And if I did replace it it would only be with a new Denso unit. Once you've pulled the intake for the first time you realize it's not very difficult and only takes about 30 minutes.
CL Community Team
Joined: Feb 2013
Posts: 2,501
Likes: 245
From: Milwaukee, Wi
That sounds good in theory, but I would have to consider the age and mileage on the car and the fact that it's already opened up. To each his own, but I hate doing the same job twice..
I agree on the Denso unit, but it would be difficult for me to take the manifold off, see the starter sitting there and not replace it with the mileage that I have on my 2001.
It could go another 50,000 miles, or it could fail next week.
Preventative maintenance is just that....
I agree on the Denso unit, but it would be difficult for me to take the manifold off, see the starter sitting there and not replace it with the mileage that I have on my 2001.
It could go another 50,000 miles, or it could fail next week.
Preventative maintenance is just that....
Instructor
Joined: Dec 2015
Posts: 878
Likes: 232
From: Arizona
While you are in there take a good look at your coolant crossovers. There are 2 cast aluminum pieces that span head to head in the front and rear. They seal with metal gaskets underneath. There is also a metal pipe that connects the 2 crossovers that is sealed with o-rings on each end. I've seen these o-rings leak.
Thread Starter
Rookie
Joined: Nov 2017
Posts: 89
Likes: 7
From: Georgia
While you are in there take a good look at your coolant crossovers. There are 2 cast aluminum pieces that span head to head in the front and rear. They seal with metal gaskets underneath. There is also a metal pipe that connects the 2 crossovers that is sealed with o-rings on each end. I've seen these o-rings leak.
https://www.ebay.com/itm/V8-Fuel-Inj...5.c10#viTabs_0
https://www.ebay.com/itm/98-10-Lexus...4AAOSwD39aZnMS
Thanks for all the info/advice everyone!
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Thread Starter
Rookie
Joined: Nov 2017
Posts: 89
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From: Georgia
Also found a few listings with both OEM knock sensors with a generic aftermarket harness included for about $26. I know OEM is usually the way to go but I wonder If the $150 or so I'd save on that harness would be worth the risk of having to take apart the intake again to replace it with the OEM harness? 
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Pole Position
Joined: Mar 2011
Posts: 2,188
Likes: 730
From: Texas
That sounds good in theory, but I would have to consider the age and mileage on the car and the fact that it's already opened up. To each his own, but I hate doing the same job twice..
I agree on the Denso unit, but it would be difficult for me to take the manifold off, see the starter sitting there and not replace it with the mileage that I have on my 2001.
It could go another 50,000 miles, or it could fail next week.
Preventative maintenance is just that....
I agree on the Denso unit, but it would be difficult for me to take the manifold off, see the starter sitting there and not replace it with the mileage that I have on my 2001.
It could go another 50,000 miles, or it could fail next week.
Preventative maintenance is just that....
Instructor
Joined: Dec 2015
Posts: 878
Likes: 232
From: Arizona
The first eBay kit you show has all the seals you need for the injectors. When my intake was off I was replacing my head gaskets and I bought the oem head gasket kit that came with every seal and gasket from the short block up. If you want to mess with your starter I would just use the rebuild kit that rkw recommends as this was the failure point on both Toyota starters I had that went bad. Both were over 300k before the contact points failed. On my pickup the contact points welded themselves together and the starter wouldn't stop running.
Pole Position
Joined: Oct 2016
Posts: 306
Likes: 13
From: Auckland
I'm doing the same project in a couple of weeks ( replace both knock sensors and heat-protecting the wiring). I won't be pulling the injectors out, they can all stay on the rails and in the manifold, as that's more money than I need to spend. I don't have a gasket kit on order, but I'll get one if I find the gaskets themselves are a bit sad (winging it big time here). The starter motor will be coming out and I'll be getting the auto sparkie across from my workshop to recondition it for me. I'll be doing video logs on how I do this. Mine is outright going into limp mode once it gets up to running temperature
Thread Starter
Rookie
Joined: Nov 2017
Posts: 89
Likes: 7
From: Georgia
I'm doing the same project in a couple of weeks ( replace both knock sensors and heat-protecting the wiring). I won't be pulling the injectors out, they can all stay on the rails and in the manifold, as that's more money than I need to spend. I don't have a gasket kit on order, but I'll get one if I find the gaskets themselves are a bit sad (winging it big time here). The starter motor will be coming out and I'll be getting the auto sparkie across from my workshop to recondition it for me. I'll be doing video logs on how I do this. Mine is outright going into limp mode once it gets up to running temperature