Ford 4.0L Index of Articles

This article will help you to diagnose diagnostic trouble codes P0171 (System Too Lean Bank 1) and/or P0174 (System Too Lean Bank 2). One of the biggest misconceptions,... [read more]

OBD II trouble code P0118 ECT Sensor Circuit High Voltage is set when the PCM in your Ford sees a fixed engine coolant temperature of -4 to -46°F (-20 to -43°C) that... [read more]

Checking whether your 4.0L Ford Explorer (4.0L Ranger, 4.0L Aerostar, or 4.0L Mountaineer) has a blown head gasket can be done with one of four different tests and in this... [read more]

OBD II trouble code P0117 ECT Sensor Circuit Low Voltage is telling you that your 4.0L equipped Ford vehicle's fuel injection computer is seeing a continuous engine coolant... [read more]

If you've been wondering if it's possible to test the thermostat (without replacing it on a hunch), the answer is YES! The thermostat can be tested while it's still on the... [read more]

If the fuel pump fails in your Ford 4.0L V-6 equipped SUV or pick up, it's not gonna' start and run. Thankfully, Ford has made it super easy to test the fuel pump on your... [read more]

A compression test will let you know if the hard to diagnose misfire (or rough idle) condition or no start condition is due to something wrong inside the engine (like worn... [read more]

Testing a Cranks but Does Not Start condition on your 4.0L Ford Explorer (Aerostar, Ranger, Mountaineer) doesn't have to be hard. In this tutorial, I'll go into the basics... [read more]

Testing the fuel injectors on the 4.0L Ford fuel injected engines in the Explorer, Aerostar, Ranger and Mercury Mountaineer can be quite a challenge since three of them are... [read more]

Testing the upstream oxygen sensors (O2S11 and O2S21), on your OBD II equipped 4.0L Ford Aerostar, Explorer, Ranger, or Mountaineer, can be accomplished in a few easy steps... [read more]