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Topic: 84 Tbird temp gauge (Read 1188 times) previous topic - next topic

84 Tbird temp gauge

I have an 84 TBird. There is a temperature sensor on the engine but I don't see a temp gauge anywhere on the gauge cluster. Also, my speedometer/odometer reads too fast. I have 70 actual miles on my external trip meter and the one on the dash shows 114.

84 Tbird temp gauge

Reply #1
What part of Nevada?

Yeah, these cars are pretty sparse on gauges. I'm assuming you have a 302? If so the computer needs to know temps, but I guess ford decided you don't.

As far as the trip computer, they should both get the same input, I'm not sure how they could read differently unless they weren't reset at the same time?
Quote from: jcassity
I honestly dont think you could exceed the cost of a new car buy installing new *stock* parts everywhere in your coug our tbird. Its just plain impossible. You could revamp the entire drivetrain/engine/suspenstion and still come out ahead.
Hooligans! 
1988 Crown Vic wagon. 120K California car. Wifes grocery getter. (junked)
1987 Ford Thunderbird LX. 5.0. s.o., sn-95 t-5 and an f-150 clutch. Driven daily and going strong.
1986 cougar.
lilsammywasapunkrocker@yahoo.com

84 Tbird temp gauge

Reply #2
What I mean by external trip meter is my GPS. I recorded a trip over the span of a week and the odometer reeds more miles than it should. The speedo is fast too. 55 MPH reads as 67 on the dash. Is there a way to calibrate that? I don't know much about these. I only got it because it was cheap. It's a 5.0. as far as the temp gauge goes, I suppose I could get an aftermarket gauge

84 Tbird temp gauge

Reply #3
The 1983-84 base cluster did not have a temp gauge, just the warning light. You speedo is off likely because of a taller tire or other tire change beyond stock. It can be corrected with a speedo gear change at the transmission.

84 Tbird temp gauge

Reply #4
Where could I find the correct speedo? Rockauto? The tires appear to be factory size but i will have to research to confirm

84 Tbird temp gauge

Reply #5
I found a website that has several different speedometer gears ranging from 16-24 teeth. Does anybody know how many teeth the original has and what type of transmission is in the 84? Thanks, sorry for all the questions.

84 Tbird temp gauge

Reply #6
The RED "Engine" light is a dual purpose, Overtemperature/Low oil pressure, warning light.
The tire pressure decal on the passenger side door jam will show the stock tire sizes.
The decal on the drivers side door jam has the codes for what drive train the car was built with. Engine, trans and rear end gear ratio.


84 Tbird temp gauge

Reply #8
The tires that are on there are slightly bigger than factory specs, which would cause the speedo to read slower. Ill try a different gear or speedo sender. For now i'll just keep using my GPS.

84 Tbird temp gauge

Reply #9
How do I know what the red engine light is indicating? The previous owner scanned it and it said bad EGR, so he replaced it and the light is still on

84 Tbird temp gauge

Reply #10
Quote from: Muiscmaster;467129
How do I know what the red engine light is indicating? The previous owner scanned it and it said bad EGR, so he replaced it and the light is still on

The light is normally on when you turn the key on without starting (no oil pressure). Then goes off after starting and oil pressure comes up.
To isolate which is bad, pull the wires off the sensors (actually switches).

Oil pressure switch has one wire (white/red stripe) and is near the oil filter.
Temp. switch has one wire (red/white stripe) and is in the intake manifold. Near the distributor. I think.

Temp sensor has two wires (light green/yellow stripe & black/white stripe) also in the intake manifold. I think. This is used by the ECU and does not turn on the red light.

84 Tbird temp gauge

Reply #11
Thanks for the diagram

84 Tbird temp gauge

Reply #12
Musicmaster,
Going off of what you said about the car going 67 when your speedo only says 55 (I think that's the order you gave), that's an overage of around 22%.  That would mean you were running a tire that was 22% larger in diameter than stock.  That would be around a 31" truck tire.  I don't think there's any way your variation is completely due to tire size.  How likely is it that someone has swapped gears in the rear end?  Or put an AOD in it when it originally had a 3sp?  That's just a big variation.  That's more than most of the 4x4 guys deal with when they go to way-oversized tires without correcting their speedo's.  I've got 32" tires on my 2wd truck and it should have 30.5", so that's a 5% increase.  At 67 indicated on the speedo, I'm really going 70 by the GPS.  Let us know if you figure out what's really throwing it off.  Later.

84 Tbird temp gauge

Reply #13
Well, I re-read your earlier post, and I had the order backward.  So everything should be opposite from what I said earlier.  Your speedo is showing 22% too high.  That logic says you're running a tire that's 22% too small in diameter.  That too is almost an impossibility, and you already said your tires were slightly taller than stock.  I'm betting you've had lower gears installed in the rear, and the speedo was never corrected.  Or you've got a 3sp trans when it should have been an AOD.  Someone else confirm that my logic is going in the right direction.  Maybe some of this helped....

84 Tbird temp gauge

Reply #14
The current tires are slightly larger than factory specs so none of this makes any sense. Are these cable driven speedos?