Another 2005 V6 4.0 1gr-fe Head Gasket Failure

Please share a link to a video or videos that were the most useful for you ... I fear I may be in this boat soon. nice work!

 

This is a good overview of the job, but you'll want a FSM handy, they miss/skip certain steps. For example, the FIPG for the timing chain cover they put on wasn't done per the manual. The May Cars DR series on the 1gr-fe is VERY detailed, I didn't use them as much because I didn't touch my valves, but they are highly regarded.

https://www.youtube.com/watch?v=pIbeoMpGxEc

https://www.youtube.com/@MayoCarsDR/search?query=1gr-fe

 

If you send the injectors out for a full refurb they will replace those parts. Thats what I did, they flow/pattern tested them and everything

 

Who did you go through and what did that cost?

 

RC fuel injection
Www.rcfuelinjection.com

Paid $150 plus shipping for 6 injectors.

 

Thanks! Sent them an email.

 

Well, I got her running last night for the first time and I'm getting a new code P0328, "Knock Sensor 1 Circuit High Input (Bank 1 or Single Sensor)", which is a bit of a bummer! The knock sensors are one of the few sensors along with the crank position sensor that I actually didn't touch during the repair job. So, I'll have to drain the coolant, remove the upper and lower intake again and see what I find. Hopefully it was just a pinched wire, or maybe I hit one of the sensors when I was messing with the big coolant tube that runs between the heads, not sure! I have a buddy that has a better code reader as well, I'll have to see if he can give me more info and see whether there are any other codes I'm not seeing. I did take it for a drive though, and it felt good. Idles well, sounds normal, but under load at certain RPM there is a noticeable shake / knock.

 

Double check all the harness connections before you tear into it.

They can be difficult to click in all the way or the plastic tab breaks from age.

 

The harness from the knock sensors terminates at the back of the RH head. Both the knock sensor harness and the RH O2 sensor are on the same bracket. Double check that. See image below.

 

I was going to link to your thread haha. Sounds like OP is good to go though!

 

Not seeing any issues there, I'll try disconnecting and reconnecting them though. I don't recall touching that connector.

 

If you didn't disconnect that harness, don't bother doing so. I disconnected mine during disassembly but I don't believe you need to in hindsight.

Assuming that code is related to the knock sensors, you will need to troubleshoot the wiring or the sensors themselves. With the heads off, this is not hard to do. With the heads on, it will be challenging. I checked my wiring harness and the knock sensors before reassembly. This does require the harness referenced in the picture to be disconnected.

Per the FSM, you can test the knock sensors with an Ohm meter. I checked my harness for continuity as I didn't realize that the harness is under tension as soon as you remove the two bolts holding the coolant pipe to the engine block.

 

I left the coolant line connected on the water outlet side, and only disconnected it from the inlet, pushed the whole assembly away from the flanges to remove the heads. If I can get that pipe disconnected from both the inlet and outlet sides I should have plenty of access to test those sensors and harness right? I don’t know if I have it in me to take those damn heads off again.

 

I pulled my upper intake off just now leaving the coolant lines attached just to poke around and noticed a little oil around one of my intake manifolds (cab side), I’m going to replace my PCV valve first and see if that could have been a culprit.

 

I hear that it is difficult, but possible to get to the knock sensors with lower intake off and with the heads in place. The coolant pipe will not come out with both heads in place. At least one head would need to come off.

Take a look at this thread.
Knock sensor bad

 

Thanks for the link, that led to me finding this video, where the guy cuts the bracket holding those 2 coolant pipes together, then he's able to disconnect the big pipe from the inlet / outlet housing and fish out those sensors with the heads in place. Looks like I have a game plan, and some parts to order!
https://www.youtube.com/watch?v=pRwMXzAH19w

 

That’s a pretty slick way of getting to the sensors. Definitely thinking outside the box.

 

zguy1 I don't know where you are in the Midwest, but if you're anywhere near the Twin Cities I owe you a cold one! If anyone has this issue in the future, the replacement part is:
4.0L KNOCK SENSOR WIRE HARNESS 82219-35020

 

I'm near Chicago, but if I was closer I would gladly take you up on that beer. It looks like you had a broken wire harness after all. I'm glad you figured out what it was. I had tried to order one of those to be safe when I was doing my head gaskets but it was on a nationwide backorder back in November of last year.

 

There are a fair number of them on eBay right now, ~$25. I’m betting I could repair the connections pretty easily but for $25 I’ll just replace it.