North American Turbocoupe Organization

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I had to store my TC outdoors this winter and of course it has been a rare brutal one. Anyway, now when I fire it up the headlights are on regardless of switch position and I can hear this crackling popping noise briefly under the dash. I'm hoping this is just a bad relay.. wondering if I'm safe to drive her around for some mechanical tests or if I'm risking a fire. No smell or smoke but definitely some noise.

Another thing is I am looking for a replacement parking brake assembly. I had mine examined at a shop and they said the actual pedal assembly is broke, hence it wont grip and hold the parking brake cable. I've never heard of that but wondering if anyone has a good source for that part. My TC is an 88.

Thanks muchly!
Any chance mice or other critters got inside and chewed some wires? Do you have automatic headlights?

Relays click, they dont make crackling or popping noises.

First thing I would do is pull out the headlight switch and look at the wiring and go from there depending on what you find.
unclefalter Wrote:Another thing is I am looking for a replacement parking brake assembly. I had mine examined at a shop and they said the actual pedal assembly is broke, hence it wont grip and hold the parking brake cable. I've never heard of that but wondering if anyone has a good source for that part. My TC is an 88.

Thanks muchly!

Ouch. Your best bet is probably the same answer I gave another poster: set up an eBay search for 1987-88 Turbo Coupe, possibly with Fox Body, Mustang and 2.3 Turbo as additional search criteria (although I'd bet that's a Thunderbird-only part).

I don't recall ever seeing anything like that on eBay, but there are sellers who part out TCs and list the results there. You'd have to ask one of them for that particular part.
I would pull the parking brake assy (3 bolts - easiest to remove the driver seat to get under there and get to them) and see exactly what is broken. I may be possible to repair it, make a replacement part out of some steel flat stock, etc. Pull it out and post a pic of it so we can see what is broken / damaged. Over the years, I have had to fabricate lots of parts for my old Tbirds since none were available.

The park brake assy is the same from 83 to 88, and not unique to the TC.... same for every 83-88 Tbird. Any decent self service junk yards near you?
Sorry for the delayed response. The weather here has been *brutal* -- we broke a record for most rain that had stood since 1950. So I left the TC alone.

Did some more hunting today. Couldn't figure out why the headlight came on when the car started and wouldn't go off. Then remembered the automatic headlights, which I have. I thought I had them off, but forgot there's the dial has that click to fully shut them off. When I did that, the lights went out. There were no popping noises, however I discovered that when I turned on the headlights via the normal switch, only the parking lights came on. If I pulled the highbeam switch they came on but only as long as I held it. Hmm. So then I played with the auto dimmer switch to see if they'd turn back on, but this time I got this 'bzzzzzzrrrrrr' unhappy sound and no action. Automatic isn't doing anything now. All the other lights work - turn signals, brakes, etc. And truth be told, I never drive the car at night, so this might have been a problem for a lot longer than I'd realized. I'm noticing too when the turn signals are on the LED for my climate control display blinks also. Not fully off but just light, dim, light dim. I don't see any evidence of rust or rodent damage looking around under the dash, not that it's easy to see stuff there. The car is still in pretty immaculate condition, no rust, etc. I'm wondering if maybe a relay or something is going/gone bad. Anyway, we have a line of decentish weather coming up this weekend so I'll finally be able to take the headlight switch out and have a look, unless you guys think maybe the dimmer switch has something to do with it. I'm going to look at schematics and figure out which is the bad guy.

And no.. in this part of BC junkyards are few and all modern. Finding 80s stuff is really getting hard. Did they use that assembly in any other Fords?

Oh one more question -- I'm looking for the correct part number for a replacement EGR valve. That is the last thing I need (my mechanic friend checked things out for me) to fix my idle problem, supposedly. But I want to make sure I buy the right thing and not some knockoff that will cause more problems than it solves. If you guys have advice on exactly where to go/whose to use I'd appreciate it.
Clicking / buzzing relays are most often caused by a bad ground. Power backfeeds thru the relays coil seeking ground since its normal ground has failed.

Why do you think the EGR valve is bad? TC EGR valves, and Ford EGR valves in general basically never go bad.
Okay.. I'll try to see what I can find. I'm sure there's a schematic somewhere I can follow to nail down where things are going wrong. Obviously the headlights are capable of working, otherwise the automatic dimmer setting would not have allowed them to come on at all before. I just don't understand the interplay between the automatic dimmer and the main headlight switch -- ie. if the former failing can cause the latter to not work either.

I don't know a lot about EGR valves but my friend is a licenced Ford mechanic and when I asked him to take a look at my idle problem he zeroed in on the IAC and the EGR. I replaced the IAC and it made a noticeable improvement, but it's still not quite able to hold a steady 1000rpm at idle. I'm not sure how the EGR influences idle but he seems to believe that's likely where the issue is.
I've seen the EGR carbon up to where it won't close completely. They can carbon up to the point where the one passage in the intake is completely blocked also. This can all be disassembled and cleaned. Note that even though it looks like there are two EGR passages in the upper intake, there is really only one.
Did you replace the IAC with the correct MOTORCRAFT replacement? ALL aftermarket IAC's are JUNK. Use ONLY Motorcraft IAC's, not just in TC's, but in ALL Fords.

If EGR is carboned up and holding the pintle open, it will cause a rough idle, but as Pete said, it can be easily cleaned out. No need to replace. Other remote possibility is a bad / leaking EGR solenoid allowing vacuum to the EGR valve when it shouldnt. This can easily be checked by disconnecting the vac line from the EGR valve and seeing if it runs better, but do this test AFTER you check the valve for carbon buildup and clean it if necessary.

FYI, many times the IAC can be cleaned out and a drop of oil put on the solenoid shaft to get them working correctly again.
Yes.. Motorcraft for the IAC. Had to ebay that one - our dealers couldn't get it anymore.

Also - armed with the knowledge of what an EGR valve is and looks like.. I found mine was missing the top bolt to the upper intake.. heh. The gasket is all flaked. Pretty sure that wasn't me -- when I removed the upper intake to get to the valve cover gasket repair I took the whole upper intake off as a unit. Now I gotta try and find the correct bolt. That has probably been leaking since I've had the car. Embarassing!
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