Removing reference sensor

[ChrisVCR]

I have a bad reference sensor and am in the process of replacing it. Car is 1984 3.2 Targa. I was able to start to remove it from the mounting bracket but as it slides out, it comes in contact with the wires and grommet going through the firewall. Cannot get a grip on the grommet to pull it but cannot see where it goes to the other side to "push" it through.

What is the trick to getting the reference & speed sensor grommet out so that I can have the room needed to finish sliding out the loose reference sensor and replace it?

[JAR0023]

I pushed mine out from the engine side with the end of a ratchet handle. A little Windex sprayed around the edges will help with extraction and insertion. -J

[steely]

if you are lucky, and the wire in the grommet that you are bumping into is the same one you are replacing, I would cut it and pull it from the engine side. You'll get a bit more room.

If it isn't, at least you will have one less cable in the grommet, and it (the grommet) will come out a bit easier.

For replacement, I found that cleaning the grommet and the firewall hole edges real good to eliminate any friction causing dirt - then use a water based lubricant to op the sucker back in.

in the future if you replace the CHT (white wire, it will come with a new grommet BTW.

[99hdtop]

Stick a small screwdriver into the hole of the ref sensor wire in the grommet and twist. Worked for me!

[Jesse16]

When I did my CHT, I'd say getting that grommet out was the worst single task. In then end, I'd say I just pushed a flat head screw-driver into the grommet edge from the side your photo shows and levered it out. The grommet is split in 3 places for the wires which is hard to see and its simply a tight fit. It does pop out. If you're replacing the sensor, then just cut that wire, pull it out and you'll have a nice hole to put the screwdriver through. Careful of the other wires obviously.

[scarceller]

Spray the grommet with Armor-All real well and let it soak a bit. Then push it through into the engine bay, push it from the out side into the bay.

[ChrisVCR]

Thanks for the replies everyone, will be giving this another try tonight.

[ChrisVCR]

Was able to get the old sensor out, the new one in and everything buttoned up but still crank and no start...

[steely]

ouch - and the speed sensor checked out ok?

Can I ask what led you to the ref sensor in the first place? Not that it isn't a bad place to start for older cars.

[scarceller]

While cranking does the tach needle move / bounce? If so the ref sensor is working.

[ChrisVCR]

Originally Posted by steely

ouch - and the speed sensor checked out ok?

Can I ask what led you to the ref sensor in the first place? Not that it isn't a bad place to start for older cars.

Fuel pump works with a test lead, replaced DME relay, coil tested ok (but not getting spark at plugs), speed sensor tested ok on multimeter but reference did not. I could see the broken plug on the reference sensor when I started testing. So, have done all that but still no start.

[scarceller]

You sure you did not swap the sensor plugs at the bracket? The sensors are identical and it's easy to plug them in backwards. Swap the plugs and try starting it. No harm done if they are backwards just the engine won't start.

Also be sure that with key in 'RUN' you hear and feel the IdleControlValve Vibrating and humming. If the DME is alive and the program code is running then the ICV will hum and vibrate with key in 'RUN'. If it does not then the DME is dead and could be the DME relay.

[ChrisVCR]

Originally Posted by scarceller

While cranking does the tach needle move / bounce? If so the ref sensor is working.

I just went and checked and the tach needle does not budge while cranking, even with the new sensor....

[Flat6pac]

At the stalk above #3, make sure the connectors on the body side clip up good and there is contact. Had 2 this year that were defective and didnt pin so the car wouldnt start.
Bruce

[scarceller]

Chris,

Let's start with basics first: if you turn the key to 'RUN' (not start) does the IdleControllValve hum and vibrate? If it does it tells us that the DME is getting power and the program code is running.

Do this test first.

Also, you will need to get a 12vdc LED test light. You can get these at Walmart Auto section for under $5.00. It MUST be the LED type for the type of testing we will be doing.

[r-mm]

There is a set screw in the flywheel (pretty sure its the flywheel not pressure plate, could be wrong) that must be gapped correctly with respect to the reference sensor. Would seem to be a difficult task with the motor in situ but I'd have to check the manual to see.

[ChrisVCR]

Turned out to be a bad DME. Sent mine off to Pelican for repair.. received it back today, plugged it in and BINGO, she started right up.