I'm getting an interimittant bad odor from the vent system when I turn on the cabin fan. The smell goes away after a short period of time. I thought it might be a coolant leak from the inside heater core but I had this checked and was told by the mechanic that he pressurized the coolant system and let it sit for most of the afternoon under pressure. There was no change in pressure so there doesn't appear to be a leak. The smell does seem very similar to the coolant I'm using.

Not sure where to go from here. Any suggestions?

I have noticed on occassions that the lid to the coolant reservoir doesn't fit correctly & sometime pops open BUT I can't see how this would give off odor into the cabin. Every now & then I get a low coolant alarm but when I check there is coolant in the reservoir and the alarm goes away.

 

The smell is from fungus growing on the moist A/C evaporator. This is what you do to help get rid of the smell. 1. Select the fresh air A/C mode with the engine running. 2. Turn the blower fan on full blast and have a few windows slightly opened. 3. Spray you favorite flavor of Lysol down into the cowl under the hood at the bottom of the windshield on the passenger side. Use about 1/4 of the can and then shut eveything off and let the Lysol work its magic. That should help quite a bit with sinky and musty HVAC smells.

 

Thanks - I'll give this a try. I did this a few weeks ago with Fabreeze but I guess Fabreeze doesn't have the killing power I need for the fugus.

 

It took a while but this may have been resolved. We thought it was a leaky heater core but could not confirm unless we removed the dash. Took the car back to the shop this past Monday because the smell started getting worse. Found a leaky thermostat housing. Had it replaced & I haven't notice a smell in 3 days. Keeping my fingers crossed. My mechanic said the smell could have been filtering into the cabin through the vents as the coolant burned off.

On the thermostat housing. It's plastic. Why would someone design a plastic housing that sits directly on a hot engine PLUS it's on the lower right corner which is susceptible to being struck by flying debris. Is it me or does this really make sense???

I am in my mid-60s, owned many, many vehicles of which all had a themostat with a metal housing. This is the first time in 45 years that I had a themostat housing leak. Could there be a connection between the leak and a PLASTIC housing. Just wondering????

 

same mechanic that pressurised it b4 and there was no leak now theres a leak ,glad you fixed it but might wanna try new mwchanic jm2cw

 

I agree with Freegdr. Although I see your point about the plastic. I have a 2001, 4.0l and my housing is metal. I wont assume they are the same between the I-6 and the V-8, I dont know.

You said that the smell goes away after a while. If it was a leaky housing the smell would get worse as the engine got hotter and the pressure built within the cooling system. Once again, i would agree with Bustedback about the fungus on the evap core. I have heard of that before and the smell can be worse than 4 unbathed fat chicks in a Hyundai in the Arizona desert in August.


or so I have heard

 

I've never been there don't think I want to.. LOL

 

Taco Bell perhaps ????????

RIZ

 

stale hairless chalupas mmm good

 

All I can say is that the vent system was sprayed with a special mold killer mixture twice by the garage. I sprayed the system a few times with Lysol following the directions of Bustedback above. Even used Fabreeze once--- Don't know what to tell you guys but the smell hasn't been back all week.

Whatever was done is working so far. Beats the cost of replacing a heater core!!!!!!!!!!!!!!

If something changes I'll let ya know.

On to the next issue- the imfamous AWD crabwalk!!!

 

If it happens again, try the suggested procedure: http://www.wjjeeps.com/hvac_clean.htm