Jeep Cherokee P0455 EVAP Code

Reader Question I have a 2001 Jeep Cherokee that while I am driving it, the speedometer and tachometer gauges drop to the bottom, and come back again after a while. This keeps going on and off. I am getting a display on the tripometer………. NO BUS. but nothing seems to affect the performance because it still runs well.

I had it analyzed by Auto Zone and they came up with the code P0455.

It states………..Evap large leak detected
1) defective, loose or missing fuel cap…..REPLACED
2) Evap. canister broke, hose cracked or not connected
3) Purge or vent solenoid defective
4) Vacuum leak at engine.

The car has 101K and I can not afford to invest too much $$$ because I intend to sell it at the end of the year, but I will like to solve the problem (hopefully not major) so the next guy won’t be stuck with a major problem. Could you tell me what would be almost the sure
shot to repair it the least expensive way?

Thanks,
Enrique,

Hey there Enrique

Interesting…if the engine performance is not affected during this drop I would suspect a problem with the PCM – power control computer (the computer) or the instrument panel itself.

There is not really much in between…the computer gets a signal from the engine, sends that signal to the instrument cluster. If the signal from the engine was wrong…I would expect the engine to run bad or not at all…since 0 RPM would mean the engine has stopped running.

BUT, since your engine runs fine, I can only assume the computer is getting proper data, it is just not sending proper data to the instrument cluster or the cluster is not interpreting the data from the computer correctly.

Since both items are expensive to guess at….I would have a mechanic look into this further. Both of these items, computer and cluster can be purchased used at a junk yard though to help offset costs.

Keep me posted will ya?

Blessings,

Austin Davis