Hi all, I bought my KJ about 6 months ago, and for the most part it's been very much trouble free and a great car to drive. I've been religiously following up on a serious of niggling issues, and the next one on my list is the apparent inability to switch to recirculated air. Despite the fact that Chrysler/Fiat, in their infinite wisdom linked the airflow manipulation to the actual operation of the cooling/heating system (every other car I've been in the air re circulation button has been totally separate), even when I switch to recirculated air, I'm still getting a significant amount of external air coming into the cabin. This is especially noticeable when going through a tunnel and all the fumes rush in, which is annoying to say the least.

Firstly, is this normal? I don't want to waste my time trying to fix something that is considered potentially 'within spec'. I'm assuming no but just thought I'd check.

In the likely event the answer is 'no', I've come across a service manual and in section 24-16 they refer to an "Actuator-Recirculation Door" and explain how this works, basically how it can be removed and re-installed. It appears that perhaps this actuator, may no longer be actuating...either that or something integral to its operation is faulty. Can anyone please confirm if they have had experience with this, and is it a simple matter of replacing the unit?

The flaps that open and close to direct the air to the various areas are driven by vacuum via small pipe coming off the intake manifold for Gassers and from the Vacuum Pump for the CRDs. If this pipe comes off then the air will flow out of the top de-mist vents no matter what else you do.

There is also a Blend Door which is driven by a small stepper motor which may be causing problems.

Finally there is a grid inside the cabin....behind the glovebox up against the firewall.. which is where the re-cycled air flows.
This grid can get clogged up with dirt so that the re-cycling function does not work too well. I know this grid exists for LHD KJs...I have not checked yet on my RHD 2002 CRD if it is also behind the glovebox!

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2002 Export CRD 2.5 Sport

Hi there Bill, thanks for your response. Mine is a CRD.

What is the best way to get to the Vacuum pump you mentioned? Directly behind that centre console?

I have seen a lot of write ups around the Blend Door issue but the symptoms don't seem to be consistent with what I'm experiencing. General airflow is not really a problem, it's more the wrong kind of airflow, ie I can't seem to shut off external air from entering the cabin.

I will also have a look at this grid you refer to, and yes, I hope it's in the same place for RHS drive otherwise to quote an Australian colloqualism, "I'm up doo doo creek"....

The vacuum pump is driven off of the Serpentine-belt and is on the front of the engine to your left as you face the engine. There are pictures up of the engine on SAMS Noob guide. You need to trace where the pipes go to from this pump...the vacuum pump is used to work the brake booster, the internal flaps and in the case of early Export CRDs to open/close the EGR via a seperate solenoid. If you do not see any obvious splits in the pipes in the engine bay you will have to pull out the whole assembly from under the console inside.

You can download the KJ Service Manual here for your year KJ which gives the theory of operations for the Blend Door and the Vacuum flaps and how to access the assemblies: http://www.colorado4wheel.com/manuals/Jeep/KJ

By the way, later KJs have seperate button for recycling air...has a "snowflake" on it apparently.

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2002 Export CRD 2.5 Sport

Lol yes that would be right!! Lol. It just makes no sense. Why on earth would you have the air internal/external distribution switch on the same dial as the directional options. So it's either internal air or the floor ducts?? And where does te internal air come out of??? Just makes no sense...

This sounds like a huge job. I'm yet to check behind the glove box but I'll make that a priority, just been super busy. Hope that's what it is, otherwise it's a world of pain.


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