90 Bronco Temp Gause Issues
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90 Bronco Temp Gause Issues
I have a 1990 Bronco Eddie Bauer with the 5l motor in it. Last Feb I had the system flushed and a new thermostat installed in it.
This winter now, when my rpms hit 2000, the temp gauge drops from dead center normal right down to ice cold, and also the heat stops working at the same time. I have to let off my gas petal, let the RPSms drop back to 1500 and then in about 3 or 4 minites the gauses goes back up and the heat works again. It is kind of fusterating because at certain speeds (especially going up hill) I am averaging 2300 or so RPS, so doing that for an hour with no heat when it is 20 outside stinks.
Anyone have any suggestions on what to check?
I also have a new radiator cap (thought maybe I was loosing pressure) and my coolant level always remains the same.
This winter now, when my rpms hit 2000, the temp gauge drops from dead center normal right down to ice cold, and also the heat stops working at the same time. I have to let off my gas petal, let the RPSms drop back to 1500 and then in about 3 or 4 minites the gauses goes back up and the heat works again. It is kind of fusterating because at certain speeds (especially going up hill) I am averaging 2300 or so RPS, so doing that for an hour with no heat when it is 20 outside stinks.
Anyone have any suggestions on what to check?
I also have a new radiator cap (thought maybe I was loosing pressure) and my coolant level always remains the same.
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Joined: Jun 2002
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From: Panama City, Fl
Could have an air bubble in the system. Remove the cap when cool. Run the engine and watch for coolant to move as the engine warms up. Let the thermostat open and close two or three times and see if the level drops. Fill to proper level.
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Mine was doing something similar last week. I had just replaced the thermostate and hoses. I bought a new thermostat and took a lot of care getting the air out. Ran it with the cap off and the heater on full. it puked several times but now it stays steady and the heater works.
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From: Cape Cod,Massachusetts
There is a company that makes a tool for this, it's called Air-Lift. Works like a charm, we use it all the time at the shop. You hook up an airhose to it and it pull a vacum on the system, if it doesn't, you have a leak. Then, you simply close the valve, remove the air hose and stick the hose into your coolant and it syphons it back in utilizing the vacum with no air to bleed.
It's simple and fast. The nice part is that it allows you to find your leak before you add coolant.
Air Lift | Automotive Topics
It's simple and fast. The nice part is that it allows you to find your leak before you add coolant.
Air Lift | Automotive Topics
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Bronco Temp Gauge
Thank you for the reply.
I tried removing the cap last Sat and let the motor run for about 10-15 minutes. I tried her out yesterday and again at 2200rpm the needle slowley dropped until I played with the accelerator to bring it under 2k. So maybe I just had the mechanic put a bad thermostat in. No biggy. Except the reason I paid to have him do it, was that dreaded lower bolt by the distributor plug. Do I have to loosten the hold down clamp (mark the location) then turn the dirtributor clockwide to move the plug so I can easily access the bolt?
Thank you guys for your replies. I have more issues with the truck, but I will post them later. I bought the truck as a project truck and pretty much replaced all the sheet metal so far mius the roof and the tailgate (which needs to just a large expense to do the tailgate and all internals).
I tried removing the cap last Sat and let the motor run for about 10-15 minutes. I tried her out yesterday and again at 2200rpm the needle slowley dropped until I played with the accelerator to bring it under 2k. So maybe I just had the mechanic put a bad thermostat in. No biggy. Except the reason I paid to have him do it, was that dreaded lower bolt by the distributor plug. Do I have to loosten the hold down clamp (mark the location) then turn the dirtributor clockwide to move the plug so I can easily access the bolt?
Thank you guys for your replies. I have more issues with the truck, but I will post them later. I bought the truck as a project truck and pretty much replaced all the sheet metal so far mius the roof and the tailgate (which needs to just a large expense to do the tailgate and all internals).
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Re: Bronco Temp Gauge
When my Bronco is going up an incline or when it reaches 55 mph the Tach reads about 22-2400 rpm. This is when the gauge starts to drop. My transmission stays at this rpm until I let up on the gas, forceing it to upshift and then it will drop down to 1500 rmp and my gauge goes back up. It does this on both Drive and Overdrive where I have to lift on the gas at 55 mph to make it shift. If I go over, say 65, it will shift normally, just this dang grey area where everything goes crazy.
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From: Gateway to the West
Ah, ok, so we are talking about shift parameters. Being a 1990 you could have one of two overdrive transmissions. Either an AOD which uses a throttle valve (TV) cable to control shift parameters or an E4OD which is a fully electronic automatic that uses no such cable.
With the AOD the TV cable can be adjusted if necessary.
With the E4OD there really is no adjustment. A flush and fluid replacement may help with this transmission since the electronic solenoids get gummed up with metal shavings and crud as the trans. fluid gets old and loses viscosity.
I will say that the E4OD shift parameters were improved with the 1994 reworking of these transmissions. However, the only way to get those improvements would be to rebuild the transmission which is no small or inexpensive task and certainly not worth the effort or expense unless it has failed.
With the AOD the TV cable can be adjusted if necessary.
With the E4OD there really is no adjustment. A flush and fluid replacement may help with this transmission since the electronic solenoids get gummed up with metal shavings and crud as the trans. fluid gets old and loses viscosity.
I will say that the E4OD shift parameters were improved with the 1994 reworking of these transmissions. However, the only way to get those improvements would be to rebuild the transmission which is no small or inexpensive task and certainly not worth the effort or expense unless it has failed.
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