How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask ttiger79 Your Own Question
ttiger79
ttiger79, Auto mechanic
Category: Ford
Satisfied Customers: 1257
Experience:  ASE Master Certified, Advanced Level Engine Performance
2207141
Type Your Ford Question Here...
ttiger79 is online now
A new question is answered every 9 seconds

i am getting a PO453 Code on My 99 Expedition ...

This answer was rated:

i am getting a PO453 Code on My 99 Expedition 4.6L This says Evap Emission Sensor Pressure High. How do I fix this I am going NUTS!!!

ThanksCustomer
Hi!
This code is for the fuel tank pressure sensor. The code description is: Fuel tank pressure sensor voltage too high. This sensor is part of the emission controls system and is primarily used to detect a leak in the evaporative system. Unfortunately, this sensor is located on top the tank, and the fuel tank will need to be dropped to test or replace the sensor. Here's where it is (number 5 in the diagram):
graphic

If you have a volt meter, I can give you some test procedures for this sensor.
ttiger79 and 6 other Ford Specialists are ready to help you
Customer: replied 9 years ago.
Reply to ttiger79's Post: Yes I have a Volt Meter.
Sure!
There's a three wire connector on the fuel tank pressure sensor. There is a brown with a white tracer, a grey with a red connector, and a red with a pink tracer. To test, disconnect the connector and turn the key on. Check to see if you have voltage on the red wire with the pink tracer. With the connector unplugged, you should see no voltage on this wire- this is the signal wire to the computer. If you have voltage on this wire, you have a short to voltage, and you will have to look for a chaffed wire or a corroded connector. If not, your sensor is bad.

Let me know if you have any more questions!
ttiger79 and 6 other Ford Specialists are ready to help you
To change the sensor, you will have to at least tip the tank down. To do a proper test, you will have to unplug the connector to the sensor. So to test, yes, you will have to at least tip the tank down enough to get at the sensor.