Hello,

Gonna do the Engine Coolant Sensor - weather permitting...

Is it necessary to drain the coolant, or can you do it with either just losing a bit of coolant with a quick "swap"

I was planning on removing the intake manifold (I read you can bungee it to hold it back)so I should have more space...

Thanks,

Colin

If the engine is cold, I would just pull it out and screw in a new one. I would take a hard look at if it is necessary to remove the intake manifold. If you do pull it back, cleaning the flame trap might be a good idea while you are in there.

Greg

As riverbend indicated--a quick swap will result in just a dribble of lost coolant. Be sure the cap is on the reservoir and no open hoses. -- Dave

No need to remove the intake manifold to do this job unless you want to do other stuff also. It's not easy to see the sensor.
I removed a few things to get better access. I opened the coolant fill cap and screwed back on. I also unhooked battery ground when changing sensors. My preference, don't know if absolutely necessary. I also remove the 25 amp fuel injector fuse, but perhaps that's also not necessary.
1. Remove the hose from the IAC to the intake manifold.
2. Remove whatever other vacuum hoses are in the way (EGR in my case).
3. Label the fuel injector wires (I use different color twist ties) and pull these off the injectors. Unscrew the ground wires on the fuel rail (there are two), then put the screws back in to hold the fuel rail.
4. Pull off wire connectors to the knock sensor, temperature gauge sensor, cold start injector. Keep track of which is which.
5. Remove the distributor cap and rotor.
6. Now pull the fuel injector wiring harness down below the level of the ECT sensor. Push all the other wiring down. You should be seeing the sensor better at this point.
7. Remove the knock sensor.
8. I believe I used a 19 mm (3/4 inch) open end wrench--regular size and a stubby version to accomplish the ECT sensor change
9. The ECT sensor uses a copper gasket. I personally like to use new gaskets.
10. You will lose only a minimal amount of coolant.
11. Search on the internet for the knock sensor tightening torque.

Hope I have not left anything out. I also used a Bosch OEM sensor.

Thanks guys,

Steady drizzle today, so I may have to postpone until tomorrow...

I was gonna replace the intake manifold gasket anyway, so I might take off the manifold...

Or, may end up doing it in two parts as I want to clean the throttle body and possibly the PCV box as well.

Thanks again for the tips,

Colin

No need to disconnect a lot of stuff. You need the right size deep socket, a wobble extension, around 10". I partially removed the intake manifold on my first attempt, and it did not give me the access I needed. I did not want to remove the injectors.

Might need to take off the accordian hose. The ECT is under the 3rd intake runner. You will not be able to see it. Find it by braille. Unclip the electrical connection. Find a way to fit (by feel) the socket over the sensor. You may need to move the engine harness out of your way, it runs vertically up/down the engine block here. Once you are able to get the socket on the sensor, attach the wobble extension. Mine unscrewed easily. Leaked very little coolant. I had to cut a few zip ties on the engine harness to get it to move, but that was easy and obvious at the time. Good luck! (my car is an '87 240).