emission issues fail

jdogg4 · May 21, 2015

when to get plates for the jeep and they said I needed an emission test.
ran over to the testing place, and didn't pass. said check engine light came on when plugging in the obdII reader for the test and popped up a fail vacuum leak. got home and I have no idea where it could be. every elbow link or T I checked even took electrical tape and taped over the connections to see if maybe the leak was from one of those locations. been out there for hours with a barbq lighter hoping to see if it would suck in a flame at some spot and nothing.

I have a 2001xj and thought there had been a write up or others with this problem in the past. which I did have some time ago found a crumbled dry rotted elbow vacuum line swapped it out and it was fine.

I've searched to page 50 and cant find anything.

need help gotta fix this in 10 days for a retest or have to pay another 25 bucks.

md21722 · May 21, 2015

Years ago I had a CEL and it was the rubber connector between lines under the drivers seat floorboard. Jeep relocated the EVAP stuff back near the tank around 2000 so there's extra lines along the frame rail.

lazyxj · May 21, 2015

jdogg4 said:
I have a 2001xj and thought there had been a write up or others with this problem in the past. which I did have some time ago found a crumbled dry rotted elbow vacuum line swapped it out and it was fine.
QUOTE]

Some 2000s and all 2001s have a pump that pressurizes the evaporative system, testing for leaks. This test only occurs when the engine is cold and last for a couple minutes.
You may have noticed a clicking sound, from the pump, at startup.

Finding a leak can be a PIA. Shops will use a smoke machine to blow smoke into the system's various parts and tubes, with the smoke escaping at the leak.
Recently my 2001 was setting a CEL for a small evaporative system leak. To track it down, a dual-stage low-pressure air regulator was used to pressurize the system to 2-psi.
I found the leak using soapy water in a spray bottle. A coupling on one of the tubes, leading the carbon canister, was cracked in a place where it could not be seen.

The most common leak is a faulty gas cap. The various small fittings on the intake manifold also regularly dry up and leak.
I found the Factory Service Manual to be helpful in learning how the system works and what and where to look.

jdogg4 · May 22, 2015

P0455 Evaporative emission system leak detected (large leak)

really wish the garage was cleaned out with all this rain it sucks trying to get this located.

got my frog togs on.

thejeepgod · Jun 18, 2015

p0455 can be related to the evap canister box under the jeep up by the rear axle. Check the physical condition of the box itself and the lines going to/from it.

143944d1282764939-check-engine-light-evap-leak-help-finding-correct-hoses-evap1.jpg

Sidewinder CC · Jun 20, 2015

Remove your gas cap and inspect its rubber seal. Many Evap issues have been resolved by replacing a defective cap.

Examine the 1/4" steel tube that goes from the charcoal canister to the top of the gas tank Roll over valve). See if it's all rusted out. There may be a hole in it.

emission issues fail

jdogg4

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md21722

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lazyxj

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jdogg4

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thejeepgod

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Sidewinder CC

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