temp sensor replacement question

Jim Chambers · 08-06-2003, 07:16 PM

Planning to replace head temp sensor in my '71 1.7. It looks like I may need to remove 3-4 intake runners to get it in and out. Can I do it without removing the intake? Appears to be almost directly behind the #3 tube.

Dave at Pelican Parts · Dave at Pelican Parts's Garage

You can, but it's not worth the hassle. Just pull the intake runner. Two nuts to remove the injectors from the runner, four more to detach the runner from the head. You'll probably want to pull the MPS and DV (one bolt and two screws) to get them out of the way as well. Then a quick pull and the runner should come out.

Recommended tool for the sensor R&R--if you do not have the "tube wrench", then take an angle grinder to a cheapie 3" long 3/8" drive extension. Knock one corner off of the square on the end of the extension that plugs into the socket. You can then put the wire of the sender into the gap where that corner used to be.

--DD

Jim Chambers · 08-07-2003, 08:40 AM

Thanks Dave. I know MPS but what is DV?

HMeeder · HMeeder's Garage

Not to contradict the great poobah DD, but there is no need to remove anything to get at the sensor. The sensor is canted at about 20 degrees off of perpendicular (towards the rear of the car) That may be contributing to your frustration.

And since you should only have to do this once in a blue moon, why destroy a tool to do it?

I take the lead and wrap it tightly around a screw driver, making a pig tail. I then take a 13mm deep socket and slide the pigtail with the connector on the inside, into the socket, then the sensor. I have removed and replaced the sensor a dozen times using this method, no problems.

Good luck!

HMeeder · HMeeder's Garage

DV = Decel Valve? (the '71 1.7 doesn't have one, BTW)

Jim Chambers · 08-07-2003, 09:17 AM

Thanks Herb. I was already planning on using the pigtail method. I think I read a post from you on that technique some time ago. Was planning to cut the wire on the old one, but getting a bit nervous about that approach in case I can't get it out. Car runs now, just not well. Guess I better look in there more closely. You are correct that I assumed it was vertical. An angle to the rear will sure make a diffference.Glad to know I don't have to worry about the DV.

mike_the_man · 08-07-2003, 11:39 AM

I have no experience with a 1.7, but on my 2.0L there was no need to remove the intake runners. I also just wrapped the wire lead tightly around a screwdriver, then slipped it in the socket. One other tip that I was told was to put a drop of crazy glue on the washer to keep it attached to the temp sensor while installing. This prevents it from falling off into the tin while trying to get it into the hole. Then, when the sensor is tightened, the bond will break and the washer will seat where it should. I hope that helps.

Cheers

Dave at Pelican Parts · Dave at Pelican Parts's Garage

I find it very difficult to get the sensor started when sitting out at the end of a deep socket. And this is something you really do not wanna get cross-threaded!! The "shallow" socket seems to not let the sensor slide back far enough to go completely inside the socket, so it starts easier that way.

I figure one <$5 extension (why grind up a good one?) is a cheap price to pay...

--DD

Jim Chambers · 08-07-2003, 06:09 PM

Thanks to all. The job is done (haven't gone on a test drive yet to see if it solved my problem). Followed Herb's advice and all went well. Did lose one washer but had another on hand. Don't think one little washer down among the head fins will do much harm. I found that the coiled wire in the deep socket kept the sensor from disappearing inside. Once the it started to thread I was able to tighten by hand until snug (put a bit of lithium grease on the threads). Now, off to test.