Look at the fuse page in your owners manual & remove the fuse for the heater/AC & see if the gauges still act crazy, maybe a cross in the wiring somewhere. What year is this?

 

Is the shroud on the radiator?

 

hey paw paw.... since its like 90+ outside, it didnt even occur to me to check the heater or vent. ill check and let yall know. and its an 89 ranger xlt with the 2.9.and yes the shroud is on. however, the fan looks like crap, could that have somethin to do with it? its all cracked and chipped.....

 

That could cause low air flow, thats why i brought up the shroud.

 

If it isn't really over heating, I think 87 XLT is on to something with it maybe being some kind of electrical problem.

I'm sorta thinking maybe a crazy ground loop problem, like a bad ground connection for the instrument cluster.

So with the blower speed at something other than AC, I was trying to see if we could maybe isolate the problem to the blower & maybe eliminate the AC clutch electricals.

From your description of the fan blades condition, sounds like it's a safety hazzard & should be replaced, before it self destructs & takes out some of those nice new things you've done to it.

Aside from being a real safety hazzard, being out of balance will play havoc with the new water pump bearings & shorten it's life. IMHO

You could probably find a good one at your local salvage yard for a reasonable price, if you don't want to spring for a new one.

Will be interesting to hear the blower speed test results, for settings other than AC high speed.

 

ok check it, it does it with the heater on, in defrost, on vent, everything, but only in high. grrrrrrrrrrrrrrr.

 

It does sound like an electrical glitch, but you want to be sure that you're not overheating, I just replaced cracked heads on my '89, know what you mean. Get a cheepie meat thermometer, don't use mom's, she'll flame. Get the type that has a long probe with the gauge at the top, make sure it can go up to 200 degrees or more. Run the engine till warmed up but with the rad. cap off, or leave it on while it warms up or you drive it a short distance if you can relieve the pressure slowly and not burn yourself, and stick the probe in the coolant. It will come up quickly and you can read the actual temp, then turn on the A/C, watch your gauges do their thing, and see if there's any change in the meat therm. reading. Or, it might be a good time to install mechanical H20 and O/P gauges. As for the fan, get that grenade out of there ASAP. Mine looked like that, I replaced it with an electric, works great. Didn't even buy one, I had an old one laying around off of something Mopar, don't know what. At least it's not off of a Chevy! Probably short out and burn up the whole truck!! -TD

 

Ok, good test psysocrazy, now we know the over heat indication is likely a bogus one, if the guage readings are normal with the fan speed on any setting BUT high.

Until you get this completely resolved I'd drive it without using MAX fan speed, just drop it down a notch so everything behaves normal & you can monitor things in that 90 deg heat.

Now to the real problem.

In my 93-99 Haynes manual electrical pictorial, it shows the fan motor & parts of the instrument pannel, (but not the guages) & many other things use the same ground point #103, so I would check that area first for problems with the ground connection or the individual ground wires.

I don't know where this ground point is located, maybe someone who does, will chime in.

Or you could call or drop by your local Ford dealer & pick their brains on his one, or ask where that common ground point is located. Bet they would share that info.

If you know where it is, you might even try a ground jumper wire, fashoned with a good heavy duty, low resistance, jump start cable, one end connected directly to the battery - post, the other end connected to a heavy guage, say a piece of INSULATED #10 or #12 guage copper probe wire.

Use the probe as a temporary ground to see if you can isolate the problem to the instrument cluster or the blower motor ground lead.

Also good as a portable ground, for trouble shooting lights, rear defroster grids, ect ect, where bad grounds are suspect.

Keep us posted on what you find.

 

ok 2 questions, maybe 3.
1. could a vacume leak have somethin to do with this?
and now a guessin game for you modern day einsteins.
in my gallery are 2 pics, one of my battery and one of the top of the motor. yall were talkin ground problems, right? well the wire pictued on top of the motor is somehow hooked up to the top right pulley. the ground on the battery runs god only knoew where. what i want to know is does anyone else have anything similar on there truck to tell me what these are, since we are talkin ground problems.
thanx
hey pawpaw what is this #103, or dad since im sure your gonna check this too, maybe you have a clue, cause i dont

 

Like pawpaw sez it could'nt hurt to check the ground. AC switch & gauges on my 87 are grounded at the same ground screw. It's behind the instrument panel on left side of the steering column.

 

did you have to pull tueinstrument panel

 

I don't think it's likely that a vacuum leak is causing the guages to go wacko.

The black ground lead going to the pulley, may be the ground connetion for the AC clutch. As rusty as it is it probably wouldn't hurt to brighten that puppy up with a wire brush, sand paper, or steel wool.

The other thing by the battery, looks like an inline fuse holder, I don't know for what, maybe the fog lights, if they were an add on.

One thing I see that is likely to cause you grief, is that clamp on battery cable connection at the post clamp. Those are meant as a temporary fix only.

I'd loose that hummer in a hurry & opt for a good set of cables.

Well I see 87XLT has spotted that ground point for you. Check it for looseness, corrosion, broken wires, ect. It'll be on a metal part of the vehicle, & a number of things make their ground connections there.

When your blower motor is on high speed, it bypasses the resistor string that controls fan speed & goes directly to ground at that spot.

My Haynes manual omitted the guage wiring page, so I don't know how they relate to this ground point, if at all.
Maybe someone else has a guage wiring page & can surmise how a bad ground, or blower motor high speed connection, could result in a ground loop, or some other electrical anomaly, that would upset the temp & oil pressure guages.

Are these two guages the only two that act out????

 

thanx pawpaw.... am currently tryin to find the ground. yep these 2 gauges are the only ones that act up.

 

"The other thing by the battery, looks like an inline fuse holder, I don't know for what, maybe the fog lights, if they were an add on.
One thing I see that is likely to cause you grief, is that clamp on battery cable connection at the post clamp. Those are meant as a temporary fix only." pawpaw


The black next to your battrey is the ground for your EMU ,there should be 2 black pig tails that come off the ground on the battery,One should go to gorund next to the radeator and the other to the ground to the ECU.
You need a GOOD set of battery cables ,Just so everything works right.there is alote that runs off the battery on your truck.

 

The ground is right beside the steering column on the left side.This is for my 87, yours might be different