OK, so somethings wrong with my heater in the bronco, and i dont think its the thermostat because the temp gauge functions normally and its were its suppose to be when ive been drive for a extended amount of time. I mean when i turn the **** to full heat, its warm, but it should be a lot warmer. So thats one problem.

The other problem is that my dang lights flicker randomly when im going down a road. seems to mostly only be when the high beams are on. The road could be flat and non bumpy as possible and the lights will flicker on and off, but the amber lights stay on.

 

What kind of bronco are we looking at here? I'm not sure on the heater stuff but maybe take a look at the switch to see if it is dirty or loose. Then see the plugs for the bulbs and see if they might need replacing.

 

Its a 1996 with the 5.0

 

Do you know what temp. thermostat you have in it? 180 should be the minimum opening temp in an EFI-equipped truck. (The computer doesn't like cooler coolant temps). If that isn't the issue, you may have air trapped in the system. The heater core in the Bronco is the "highest point" in the system and if enough air has gotten in, the coolant won't flow up and through the core properly.

To troubleshoot, check to ensure that BOTH coolant lines to the core are indeed hot. If neither is hot, air in the system is the most likely problem. If only one is hot, chances are, you have a clogged core. With a clogged core, replacement is typically the most effective solution.

With air in the system, let everything cool down and disconnect the return coolant line (NOT the one coming directly from the water neck) from the core. A small amount of coolant may escape but if there is air enough air in the system, there won't be much. Its at times like this when I take the opportunity to splice the coolant return line with a fill port about a a foot to 18" from the core. This way, if the condition occurs again, the system is easily refilled. They are inexpensive from most parts stores and come with a threaded cap to seal the system. Once this is in place, you can back fill the system from the high point to ensure that the entire system is full. This should restore your heat.

As for the flickering high-beam headlamps, you can check for loose or frayed wiring out at the headlamps but based solely on past experience, I'd have a look at the main light switch. The OEM units have a terrible service record and frequently burn up contacts in the connectors.

 

stock tstat is a 195 for our broncos with EFI.

check your headlight wiring, if you find issues look here for a replacement headlight harness.
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