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Freaky gauges and more

Don't know if any of you have seen my Questions questions post, but I'm having a couple of issues with the 88TC I just acquired.

First thing I noticed was the temp and oil pressure gauges would read high when the lights are turned on. I just ran a simple test to see if this happened from "dead cold" and it didn't seem to. So I fired the TC and let it sit, watching the gauge and occasionally turning the headlights on. Nothing seemed to happen till the pointer got to the "O" in "NORM" Then with the lights on the pointer went to the top line of "NORM" range within about 20 seconds. Turn the lights off, and the gauge will begin to drop....slower than Christmas. Also, at about that point on the gauge the radiator started flowing water.

So I put the radiator cap back on and continues to let it sit. Eventually the LEFT fan came on. (I'm guessing this is for cooling, and the RIGHT is for the A/C?) At any rate, the longer it runs, the higher the gauge reads. And with the headlights on, the gauge will PEG and stay there as long as the lights are on.

I'm thinking there is something flaky with the IVR and am going to replace it. I've also got a new temp sender, thermostat, and water pump (which came with the car). But after making a 3 day 2000 mile trip I just can't believe the car is actually overheating. The car ran beautifully.

So....you think the IVR is the culprit?

I'm changing the headlamp switch also because if the headlights AND fogs are BOTH ON, they will eventually BOTH start to flash off and on. Ya think the switch is the most likely cause?

Also, what about that passenger's side fan? Is that one dedicated to the A/C? It didn't come on when I turned the A/C on. But by this point everything was a bit warm to be pulling connectors and checking for voltages at the fan.

Any and all help appreciated.
5 Mopars, an S-197, and the Turbo Twinkie[SIGPIC][/SIGPIC]

Freaky gauges and more

Reply #1 –
Not sure about your other issues but I do know your light switch is bad if your lights starting flashing on and off.  What's happening is the switch is getting hot and causing a short which in turn makes the lights flash on and off.

As far as I know, both fans should be working, I know on my TC I have two fans pulling and one fan in front of the radiator pushing air through.  So you may have a bad switch or connection there also.

Most likely you have a short going on somewhere, it may well be the IVR but, I don't really know what to tell you there.

Wish I could be of more help, let us know what you came up with.
[SIGPIC][/SIGPIC]1987 Turbo Coupe
LenTech Strip Terminator Valve Body AOD, 302 Stroker (cid 347) 10:1 Compresion
Ford Racing Cast 3.40 Crank Balanced, Pioneer Forged 5.4 Rods, Mahle Flat Top Pistons 4.40, Edelbrock Performer RPM Alluminum Heads
Ford Racing 220 Duration 500 Lift Cam, Edelbrock Performer Intake Manifold , Edelbrock 800 cfm Performer Carb
Flowtech Headers, KYB Adjustable Shocks, Dyna Max Exhaust
355 Posi Rearend

Freaky gauges and more

Reply #2 –
+1 on the headlight switch. It has a built in circuit breaker that opens when it gets too hot. It could be a loose connection to it that is getting hot.

Freaky gauges and more

Reply #3 –
Yep. I'll be real interested to see if the used switch I have on the way is in any better shape than the one in the car. Worse comes to worse, I'll get new headlights and fancy new bulbs for better lighting. That will have to do till the new switches are available again.....IF that happens


Tomorrow I'll be doing another check, this time with a thermometer so I can see what it's really doing.
5 Mopars, an S-197, and the Turbo Twinkie[SIGPIC][/SIGPIC]

Freaky gauges and more

Reply #4 –
in the mark when i turn on my head lights my tach and gas gauge peg
bad ground to gauges
RIP 1988 and 1990 Lincoln Mark VII LSC
I welcomed the dark side and currently am driving a 2000 Dodge Durango SLT plus, with a 5.9, Code named project "Night Runner"
Shes black on black, fully loaded, with headers, 180 tstat, e fan, straight exhaust into a cherry bomb vortex ler, full tune up, ported intake and T/B, MSD coil, and round aircleaner.
Mods to come: Fully rebuilt and heavily modded 46RE, and a richmond rachet locker.
my $300 beater ;)
R.I.P Kayleigh Raposa 12/18/90 - 2/24/07

Freaky gauges and more

Reply #5 –
I'll check the ground when I replace the IVR. Thanks for that info!!
5 Mopars, an S-197, and the Turbo Twinkie[SIGPIC][/SIGPIC]

Freaky gauges and more

Reply #6 –
im not sure if the tbird is the same as far as gauge wiring, but what we have to do is splice in a wire on the ground and ground it and it fixes the issue.
RIP 1988 and 1990 Lincoln Mark VII LSC
I welcomed the dark side and currently am driving a 2000 Dodge Durango SLT plus, with a 5.9, Code named project "Night Runner"
Shes black on black, fully loaded, with headers, 180 tstat, e fan, straight exhaust into a cherry bomb vortex ler, full tune up, ported intake and T/B, MSD coil, and round aircleaner.
Mods to come: Fully rebuilt and heavily modded 46RE, and a richmond rachet locker.
my $300 beater ;)
R.I.P Kayleigh Raposa 12/18/90 - 2/24/07

Freaky gauges and more

Reply #7 –
Man I hate cutting and splicing factory harnesses. But if it's got to be done, it's got to be done.

Again, thanks for the tip!!!
5 Mopars, an S-197, and the Turbo Twinkie[SIGPIC][/SIGPIC]

Freaky gauges and more

Reply #8 –
not a problem
like I said thats in the mark, which is VERY similar to the bird
not sure if it makes a difference in the bird or not
http://www.lincolnsonline.com/tech/00109.html
RIP 1988 and 1990 Lincoln Mark VII LSC
I welcomed the dark side and currently am driving a 2000 Dodge Durango SLT plus, with a 5.9, Code named project "Night Runner"
Shes black on black, fully loaded, with headers, 180 tstat, e fan, straight exhaust into a cherry bomb vortex ler, full tune up, ported intake and T/B, MSD coil, and round aircleaner.
Mods to come: Fully rebuilt and heavily modded 46RE, and a richmond rachet locker.
my $300 beater ;)
R.I.P Kayleigh Raposa 12/18/90 - 2/24/07
 

Freaky gauges and more

Reply #9 –
The factory manual has the Mark, Tbird/Cougar, and Mustang bundled together. So I'm guessing they're all pretty close to the same. I'll take a look to see if it looks like it really is.  If I learn anything, I'll pass it on.
5 Mopars, an S-197, and the Turbo Twinkie[SIGPIC][/SIGPIC]

Freaky gauges and more

Reply #10 –
Been studying jcassity's 87 EVTM for a way the temp gauge and headlight switch can be connected.
There is an 18 pin connector on the instrument cluster. Pin 9 is the temp gauge input, red/white wire.
Pin 13 is hot with the headlight switch on for illumination, light blue/red wire.
Pin 12 is the ground for the illumination, black wire.
I think this connector is the type that slides onto a printed circuit board with contacts on both sides of the board.

jcassity...If you could rescan page 105 and post it up, it has a layout of connector C285. Mine is too fuzzy to read.

Freaky gauges and more

Reply #11 –
turbo 88
while you are in there in such an easy working area around the headlamp switch,, set your radio to AM whatever low band,, wiggle test wiring and listen for pops or cracks.

Helps isolate high resistance / intermittant or defective connections just about anywhere.  Thanks TOM for that trick btw!!


softtouch
Yeah, page 105 sucks ass berries! gotta rescan but im beat now.  I said it sucked a year ago and it still remains the same.  I gotta get off my lazy butt and fix a few of those puppiesy prints.

here are shop manual pages for now.>>>>located in my DIY link.  see page 2 of this thread http://www.foxtbirdcougarforums.com/showthread.php?t=17053

Freaky gauges and more

Reply #12 –
who was it that did a write up on that thermal fuse in the light switch>  cougarSE im pretty sure?
whoever it was, they also posted pics and i forgot to steal it.
now we need it.

where you at claude?

Freaky gauges and more

Reply #13 –
UPDATE

Yesterday I bought a digital thermostat to see what the actual temp of the TC was. So today I dropped the lift, fired it up, and "checked it's temperature".

Ultimately I let it run in the shop for about 40 minutes. I ran it with, and without the lights on. And while the gauge didn't peg, (with the lights on) it was almost to the red. The GOOD news is, it isn't running hot. At about 218' the fan (right side) came on, and it flowed water like mad. And when the temp got back down to 190something the fan would shut off.

I was double checking this using my SnapOn laser on the radiator right where the top hose connects. And as usual, when I turned the lights off, the gauge dropped back down to the "OR" range (think "NORM")

SOOOO......now I know it isn't running hot, although I intend to drive it and take the SnapOn with me to re-check the check. And when the headlight switch and the IVR get here I'll change them, reground the gauges, and see what happens.
5 Mopars, an S-197, and the Turbo Twinkie[SIGPIC][/SIGPIC]

Freaky gauges and more

Reply #14 –
i would re ground them for shiznits and giggles. I did my car today and it COMPLETELY changed how my gas gauge reads.
RIP 1988 and 1990 Lincoln Mark VII LSC
I welcomed the dark side and currently am driving a 2000 Dodge Durango SLT plus, with a 5.9, Code named project "Night Runner"
Shes black on black, fully loaded, with headers, 180 tstat, e fan, straight exhaust into a cherry bomb vortex ler, full tune up, ported intake and T/B, MSD coil, and round aircleaner.
Mods to come: Fully rebuilt and heavily modded 46RE, and a richmond rachet locker.
my $300 beater ;)
R.I.P Kayleigh Raposa 12/18/90 - 2/24/07