So, after my mysterious 1.5 hour non-start situation last week I've taken a few countermeasures to prevent this from happening again. I have changed all my vacuum lines with new ones, adjusted idle speed (necessary after new vacuum lines), adjusted the valve clearance, verified all electrical fuses & relays for contact. Wow I'm running much better now! However this weekend I plan on changing my CHT otherwise known as "temp sensor II" I ordered the CHT from Pelican & was looking at the location on the engine last night. It's kind of under the intake air manifold pipe for -I think- #3 cylinder. Before I dive into this CHT change, are there any special tools or magic tricks necessary to access the CHT, under the manifold pipe?

Yoei66

You are going to need a 13mm deep socket that you grind out a notch in the top so the wire has a place to go.

It's a real fun job with the engine in the car.

theres a cheap and a slightly more expensive method

the more expensive way is take a short socket extention and grind of a corner then put the wire off of the cht out the corner that you ground off and use a ratchet like normal.

the cheap way is to put a deep socket on it and use a small pair of visegrips to turn the socket.

either way it not too hard but make sure you use anti seize and tighten it as tight as you can with out stripping it.

OK, I searched through the island of unwanted & abandoned tool at work. I found & modified a 13mm deep socket w/ a notch for the wire. This should do the trick. My quality inspector agrees.

As long as the spade connector will fit throught the hole it should work fine.

Grinding the corner from the male end of an extension is an effective way to do this. You have to be really careful to get the socket fully seated on the sensor, and there's substantial risk that the sensor will stick in the head and destroy the threads on removal. If that happens, the tin has to come off, and a 10 x 1 Timesert needs to be installed. Be careful NOT to get any antisieze on the copper washer, as that's the ground for the sensor. BTW, the new sensors don't ordinarily come with the washer. You NEED to have it, and it should fit well in order to be effective. Good luck, you're gonna need it, along with a LOT of patience. The Cap'n

According to a D-Jet "Expert", try putting a paper clip between the spade connectors to the CHT. He swears this will work and I would like to know if he's full of crap............

QUOTE (SLITS @ Mar 18 2005, 10:45 AM)

According to a D-Jet "Expert", try putting a paper clip between the spade connectors to the CHT. He swears this will work and I would like to know if he's full of crap............

Ron,
I'm confused. Do you mean between the two electrical connections? If so, why would I do this?

i just curled up the sensor wire and stuffed it into a 1/4" drive deep socket with an extension. it worked well. if you cram a little piece of paper or whatever between the cht sensor and the socket wall then it wont fall out or move around when you go to screw it in.

Great post mattillac... I was just sitting here wondering if the coiled-up wire would fit inside a deep socket instead of having to pull it out through a hole. If it does, no need to grind up a tool.

no need to grind any tools. i barely have enough tools to work on my car, let alone grind holes in them. i do like the idea tho.

OK went with earlier advice on grinding the tool. Water under the bridge is water under the bridge. grinding issue closed.

I am slightly concerned about the chance of stripping out the threads when removing the sensor. Im thinking is better to do it with the engine stone cold. any advice on measures I could take to prevent stripping threads on removal.

shoot it with a bit of PB Blaster before and as you get it going.

other than that, hold your breath and go for it!

Maybe use some WD40 and let it soak in for an hour? That may help loosen it up if it's really jammed in.

Cool! Thanks for the advice everyone, this will be a lot easier now!

QUOTE (Yoei66 @ Mar 18 2005, 12:11 PM)

QUOTE (SLITS @ Mar 18 2005, 10:45 AM) According to a D-Jet "Expert", try putting a paper clip between the spade connectors to the CHT.  He swears this will work and I would like to know if he's full of crap............ Ron, I'm confused. Do you mean between the two electrical connections? If so, why would I do this?

He indicated it would simulate a "good CHT" (as long as the CHT was making a good ground) and the car would run. Yes between the electrical connections in the engine compartment.

I've never had a chance to try it.

The person that told me this was the Owner of Fuel Injection Corporation (the company that bought Brett Instruments), when I was discussing the cost of getting MPSs rebuilt.

Thanks Ron.
Thanks for the clarification & the idea. I assumed this is what you were suggesting, how to trick the FI controller unit if the CHT sensor has failed. My CHT hasn't failed completely yet. However, I do suspect that it did have an intermittent failure last week, causing my breakdown. I'm almost curious enough to leave it in & try the paperclip trick, but with a new CHT in hand I think I'll install it now. I will remember this trick for the future, as I do more time in 914 world.

QUOTE (p914 @ Mar 18 2005, 02:35 PM)

Maybe use some WD40 and let it soak in for an hour? That may help loosen it up if it's really jammed in.

Contrary to what by this time is a full fledged urban legend, WD 40 is NOT a penetrating oil. It is a "water displacer", hence the name. Another lister mentioned PB Blaster. While it's a good penetrant, it won't get past the copper gasket (besides ensuring good electrical contact, that's what the gasket is there for), so it's a waste of time and just makes a mess. The Cap'n