I have a 1998 F150 with 5.4 and the heater will not blow hot air and the temp gauge never gets above normal. I have changed thermostats and flushed the cooling system. The heater will not blow hot air, not even after a 100-mile drive.

I have a 1998 F150 with 5.4 and the heater will not blow hot air and the temp gauge never gets above normal. I have changed thermostats and flushed the cooling system. The heater will not blow hot air, not even after a 100-mile drive.

I have a 1998 F150 with 5.4 and the heater will not blow hot air and the temp gauge never gets above normal. I have changed thermostats and flushed the cooling system. The heater will not blow hot air, not even after a 100-mile drive. No one can tell me what to check for. Any suggestions will be very helpful.

The heater core may be plugged with rust. Have the system flushed. If the heater core begins to work, great! If it begins to leak after the flush, replace it. Heater core failure is a common Ford truck issue.

—Jim O’Neill
Chino Autotech Inc.

You May Also Like

A Closer Look at Stabilizer Bars

You may know them as sway bars or anti-sway bars.

Stabilizer bars. You may know them as sway bars or anti-sway bars. You may know them as roll bars or anti-roll bars. They’re all the same thing, and it’s generally understood they improve handling … but how?

Any time a vehicle is turning, the forces that act upon it cause the body to roll, sway or tip away from the turn. It’s the laws of physics at work. In extreme situations, these forces can cause a vehicle to tip over, though that’s generally only the case with taller trucks and vans, and rare at that. You really have to be moving for that to occur. The real factor is how they negatively affect handling and how a stabilizer bar can prevent it from happening.

Understanding the Emission-Control System

These components should be high on the list of parts you sell.

Bleeding the Brakes

It’s a simple concept, but not without the occasional headache.

The ‘Other’ Gaskets

Why should head gaskets get all the glory?

Why Private Equity Loves the Automotive Aftermarket

The same qualities that make the aftermarket a great place to do business make it a compelling investment for PE.

Other Posts

How to Change a Headlight Bulb

There’s always an opportunity to help your DIY customers do the job right.

Hydraulic Suspension Bushings

They can isolate noise, vibration and harshness from entering the vehicle cabin more effectively than standard bushings.

Paul McCarthy: This Is a Historic Moment for Consumer Choice

McCarthy calls the REPAIR Act the most important federal legislation for the aftermarket since Magnuson-Moss.

A Closer Look at Lincoln-Mercury

The Mercury brand was shuttered in 2010, while Lincoln is enjoying a bit of a renaissance.