Is your AC not working so well? Check this out...

[VetteMed]

Got a nice surprise this morning, while disassembling the heater/AC box... When I bought my Z (1991 #302), the PO reported that the AC worked ok but lost refrigerant due to a leak. I figured, I may as well replace as much of the system as possible, given the age and condition (rusty fittings, etc).

Here's what I found on the evaporator core:







So, if your AC isn't as cold as it should be, or if the airflow from your vents isn't as much as it should be, you might want to pull the covers off the evap/heater box... This one was clearly allowing very little airflow.

[1989ZR1#74]

That looked exactly like my 89 L98 A/C evap core. Same symptoms etc. It appeared that a mouse lived there for awhile. Blew my socks off after I cleaned it up...

[bdw18_123]

Good tip VetteMed, I'll have to check mine now. Didn't think that much crap would be able to get in there, but I guess it does somehow.

[scottfab]

WOW so the evap core is also the filter, interesting design.
I hope this inspection is doable without taking the 1/4 panel off.

[tomtom72]

That's just plain ole fugly!

Gill panel, rear inner fender liner, proly middle fender liner also and washer bottle from the looks of things......heck might as well do the "Gordon" trick on that SIR sensor and install headers while you're there....


Next winter......maybe.

[bdw18_123]

Originally Posted by tomtom72

......heck might as well do the "Gordon" trick on that SIR sensor...

What exactly is this "trick" and what does it do?

[VetteMed]

Originally Posted by tomtom72

That's just plain ole fugly!

Gill panel, rear inner fender liner, proly middle fender liner also and washer bottle from the looks of things......heck might as well do the "Gordon" trick on that SIR sensor and install headers while you're there....


Next winter......maybe.

Yep, lots of disassembly to get the box apart, but I was "in there anyway"...

I am wishing I had the spare funds to put headers on right now, but it's a no-go right now. What's the "Gordon" trick, for future reference?

[tomtom72]

The "Gordon" trick is the re-grounding of the SIR sensors. In the top picture you can see the small black box with the yellow wiring coming from it. The evap box leaks water on to the frame and the eventual rust causes the sensor to loose the ground and set an SIR DTC, thew infamous INFLREST light on the DIC.

Gordon Killebrew (sp?) said to unbolt the sensors, clean up the corrosion, use a star washer and some dielectric under the mounting tab and clear the code.

http://zr1netregistry.com/Old_Proj/old_proj7.htm

The one on the driver's side is just in front of the battery tray.


Tom

[VetteMed]

Originally Posted by tomtom72

The "Gordon" trick is the re-grounding of the SIR sensors. In the top picture you can see the small black box with the yellow wiring coming from it. The evap box leaks water on to the frame and the eventual rust causes the sensor to loose the ground and set an SIR DTC, thew infamous INFLREST light on the DIC.

Gordon Killebrew (sp?) said to unbolt the sensors, clean up the corrosion, use a star washer and some dielectric under the mounting tab and clear the code.

http://zr1netregistry.com/Old_Proj/old_proj7.htm

The one on the driver's side is just in front of the battery tray.


Tom

Ahh, makes perfect sense. Thanks for the tip!