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Engine Code P 0442

Hi folks,
I have my first engine code at about 65000 miles: P 0442. 2 questions if
you please:

1) What is this?

2) What do I need to do about it?

Thanks very much,
Tomes
2002 TJ 4.0, no AC

Re: Engine Code P 0442

1) Small leak detected in evaporitive purge system.
2) Apart from the obvious, check the petrol tank fuel cap.

Dave Milne, Scotland
'91 Grand Wagoneer, '99 TJ

"Tomes" <XXtomanml@earthlink.net> wrote in message
news:Mezze.6555$aY6.724@newsread1.news.atl.earthli nk.net...
> Hi folks,
> I have my first engine code at about 65000 miles: P 0442. 2 questions if
> you please:
>
> 1) What is this?
>
> 2) What do I need to do about it?
>
> Thanks very much,
> Tomes
> 2002 TJ 4.0, no AC
>
>

Re: Engine Code P 0442

http://www.wjjeeps.com/faultcodes.htm
God Bless America, ßill O|||||||O
mailto:-------------------- http://www.----------.com/

Tomes wrote:
>
> Hi folks,
> I have my first engine code at about 65000 miles: P 0442. 2 questions if
> you please:
>
> 1) What is this?
>
> 2) What do I need to do about it?
>
> Thanks very much,
> Tomes
> 2002 TJ 4.0, no AC

Re: Engine Code P 0442

"Tomes" <XXtomanml@earthlink.net> wrote in message
news:Mezze.6555$aY6.724@newsread1.news.atl.earthli nk.net...
> Hi folks,
> I have my first engine code at about 65000 miles: P 0442. 2 questions if
> you please:
>
> 1) What is this?
>
It means there is a leak in the Evaporative Emissions Control System.

> 2) What do I need to do about it?
>
Put the gas cap on securely.

Check it out,
P0442 OBD Trouble Code

Technical Description
Evaporative Emission Control System Leak Detected (small leak)

What does that mean?
This indicates a fuel vapor leak in the EVAP control system. It means a very
small leak has been detected. In fact, the leak can be from a hole as small
as 0.04" in diameter. The (EVAP) emission control system prevents the escape
of fuel vapors from a vehicle's fuel system. Fuel vapors are routed by hoses
to a charcoal canister for storage. Later, when the engine is running a
purge control valve opens allowing intake vacuum to siphon the fuel vapors
into the engine.

Symptoms
You likely won't notice any drivability problems.

Causes
A code P0442 most likely means one or more of the following has happened:

A loose or improperly affixed gas cap
A non-conforming gas cap (i.e. not factory/original brand)
A small leak/hole in a fuel vapor hose/tube
Other small leak in EVAP system
Faulty vent o-ring seal

Possible Solutions
With a P0442, the most common repair is to:

Remove and reinstall the gas cap, clear the codes, and drive for a day and
see if the codes come back.
Otherwise, replace the gas cap, or
Inspect the EVAP system for cuts/holes in tubes/hoses