what to do to get rid of p0442
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Joined: Mar 2003
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From: North Carolina
what to do to get rid of p0442 small evap leak is the definition, its been coming on and off maybe 3 times in the last 8-12 months. waht in the system can be screwed up and cause this code to come on? i want to saw i saw the code after i washed teh engine bay, so i wonder if the valve up there is shot. just looking for things to check out that would make it come on every once in a while. thanks
Last edited by WS6FirebirdTA00; Sep 2, 2018 at 07:31 AM.
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From: sojourning....looking for my city whose builder and maker is God.
Originally Posted by WS6FirebirdTA00
small evap leak is the definition, its been comming on and off maybe 3 times in the last 8-12 months. waht in the system can be screwed up and cause this code to come on? i want to saw i saw the code after i washed teh engine bay, so i wonder if the valve up there is shot. just looking for things to check out that would make it come on every once in a while. thanks
P0442
DESCRIPTION
The EVAP SMALL LEAK TEST is based on applying vacuum to the EVAP system and monitoring vacuum decay. This diagnosis will detect a leak as small as .040 in. in the EVAP system. The Powertrain Control Module (PCM) monitors vacuum level via the fuel tank pressure sensor input. At an appropriate time, the EVAP canister purge valve and the EVAP vent valve are turned ON. This allows the engine to draw a small vacuum on the entire evaporative emission system. After the desired vacuum level has been achieved, the EVAP purge valve is turned OFF, sealing the system. A leak is detected by monitoring for a decrease in the vacuum level during a given time period. A small leak in the system will cause DTC P0442 to be set.
CONDITIONS FOR RUNNING THE DTC
- DTCs P0107, P0108, P0110, P0112, P0113, P0115, P0117, P0118, P0121, P0122, P0123, P0125, P0440, P0443, P0449, P0452, P0453, P1106, P1107, P1111, P1112, P1114, P1115, P1121, and P1122 are not active.
- The system voltage is between 10-18 volts.
- The startup ECT is between 4-30°C (39-86°F) , but the startup ECT is not more than 8°C (14°F) more than the startup IAT temperature.
- The startup IAT is between 4-30°C (39-86°F) , but the startup IAT not more than 3°C (7°F) more than the startup ECT temperature.
- The fuel tank level is between 20-85 percent.
- The Barometric Pressure (BARO) is more than 75 kPa.
- The Vehicle Speed Sensor (VSS) is less than 75 mph.
The EVAP system can achieve vacuum but a vacuum decay is detected during the diagnostic test.
ACTION TAKEN WHEN THE DTC SETS
- The control module illuminates the Malfunction Indicator Lamp (MIL) when the diagnostic runs and fails.
- The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame/Failure Records.
- The control module turns OFF the Malfunction Indicator Lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
- A current DTC "Last Test Failed" clears when the diagnostic runs and passes.
- A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
- Use a scan tool in order to clear the MIL and the DTC.
The EVAP system tests run when the engine is first started and meets the Conditions For Running The DTC. To aid in locating intermittent leaks, use the EVAP pressure/purge diagnostic station to pressurize the EVAP system. Move all EVAP components while testing with the Ultrasonic Leak
Last edited by Lady Redhawk; Nov 29, 2005 at 07:15 PM.
Thread Starter
Joined: Mar 2003
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From: North Carolina
thanks for the info, ill check it all out. its just odd that it only happens sometimes and not all the time. im wondering if it could be a leaking gas cap. ill go through that list if my POS internet will load it
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From: Live Oak, FL - in the woods where the creatures lurk.
Originally Posted by Lady Redhawk
After all that, it might just be your gas cap. lol 
I'm -guessing- you have the Helms, LOL.
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From: sojourning....looking for my city whose builder and maker is God.
Originally Posted by gwj
You should take my poll in the General Maint section.
I'm -guessing- you have the Helms, LOL.
I'm -guessing- you have the Helms, LOL.
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Verdad Gallardo Thread Starter
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From: North Carolina
came up again today, the past 2 times it came on was after a pretty cold start after taking the car out, driving, letting it sit a few hours. im going to change the valve or whatever it is on the intake manifold (well beside it) with my friends and see if the problem follows to his car. if it does i know what it is and i save 80 bucks from going to the dealer, if not ill keep swapping **** haha
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From: Jacksonville, FL
Finally got a hold of him - couldn't tell me exactly where the leak was but thinks it was in the plastic fuel fill tube - they used epoxy to seal the leak. Also, he had his fuel pump replaced by the same shop so they didn't charge him because they said it might have been their fault - so probably not the same problem your having.
I have had this code show up once in a while ever scence 8,000 miles. never figured it out sometimes takes car 3-4 months to through the code or mabe the next day I just clear it and keepp going. never casue any problems
Thread Starter
Joined: Mar 2003
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From: North Carolina
same thing here except its come on 2 times now. hopefulyl i can swap that piece and see if that fixes it. otherwise i have no idea. this all happened before i did my fuel pump to or else i would blame it on myself.
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Finally got a hold of him - couldn't tell me exactly where the leak was but thinks it was in the plastic fuel fill tube - they used epoxy to seal the leak. Also, he had his fuel pump replaced by the same shop so they didn't charge him because they said it might have been their fault - so probably not the same problem your having.
