I have the same problem after heads/cam and uncoated headers. I'll make a trip to Harbor Freight this weekend and check the pressures.

This happened once before and the dealer replaced an expansion valve. Seemed fine for a long while, but the extra heat from the higher compression bumped it over the top again.

My original thread (at one point they thought it was the alternator):

http://forums.corvetteforum.com/c6-z...off-wierd.html

 

NJ let me know what u find out my Heads and cam Z06 does the exact same thing only difference its 110 degrees here... PM if u find a solution..

R.

 

Well, well......
Seems I can add this to my list of supercharged woes....
A/C runs great. Always has. But now, if I sit in traffic (when the A/C is most desired) she shuts down. Last weekend we roasted in traffic.
And I'm hearing on the forum that this is caused by excessive heat build up due to supercharger? Nice. More to fix....more $$ to spend. Wonder if I can get this car stolen......

 

where do you live, leave the keypad on the rear left tire

 

I know where he lives, leave the key pad on the left rear tire!


Seriously though, it is generally an overfilled situation, and I have seen in both SC and NA applications.

Peter, if you would like to stop down and have us take a look at it just let me know. It's possible it was over filled when you had your engine installed elsewhere. I dont think we thought to check that when we gave it the look over for you. (hard to think of everything)

 

C6 H/C car here doing the same thing as many have mentioned above.

I noticed a sensor just in front of the fuse box near the high pressure port and am guessing thats the little guy telling the a/c to cut off.


When removing freon, is this done from just the low side or the high side as well?

 

Thanks Doug. Actually....you read my mind, as I was to make appt in July for other stuff....still thinking of meth injection.
Also, pick your brain on getting the running temps down......radiator swap? Or at least checking that all up front is as clear of crap as possible

 

Yea....actually, folks in my household do just that when getting service at local STS.
As a confirmed Brooklyn NY guy... I cringe over that amount of trust in my fellow man. Seems the surburbanites of NJ had a very different upbringing

 

Yes we did, and still do. Ironically my Ac is doing the same as most on here.

 

I too am having the same problem...I'm sure all these things are reasons and solutions for fixing this..One thing I have done was to press the recirculation button and the AC kicked right back on...Doesn't make any sense to me, but it has worked...I'll be checking in with the guys at ECS to solve this...I still need my gauges installed in my new leather wrapped pod...
Don't forget about me guys....

 

2010 Grand Sport Vert

I had an issue with AC but its a bit different. I had a bad compressor (took a while to TS) and had that, and one of the schrader valves replaced under warranty. Valve was replaced first, then again after the thought was the first time it was due to a compressor over pressure issue and that blew the seal the first time, and then again.

Now I do get operation intermittently (compressor clicks on and off) and I never had that before, but wouldn't stay on at idle or in traffic. So we did some more troubleshooting and here's what the dealer did.

Suspecting an issue with the vararam I installed he twisted it up and away from the cut shroud and covered that hold completely with cardboard. When that was done AC runs fine, even at idle. So, we figured the very small (and I mean small, at most on some of the radius cuts its 1/2 inch from the side of the air box) openings between the shroud cuts and the air box were enough to screw up the air flow under the shroud. I went out a got some wider weather stripping, actually pipe insulation with the split in the middle and stuffed that around. That closed the gaps up a lot. There are still very small cracks so its not air tight but it seems tighter. But remember, these gaps were not huge to begin with. I did call vararam and at their suggestion I also removed a rubber cover that's under the front of the car, between the nose and the radiator (get under the car and you'll see what I mean). Its not the rubber air dam, its a cover that's right before that. That opens up a pretty wide slot under the car that allows air right in front of the radiator. Of course I have no idea why that's there so who knows what else will happen but vararam says he's removed these a lot for better air circulation.

So, now the car coolant runs cooler, in the 190's and yes, it blows cold air when the AC is on, but only when I'm moving and its not too warm out (today it was 90 and it did mostly blow hot... or at least warm, and the compressor cycled on/off/on/off, but tonight its int he 70s and the air is cold again). But if I let it sit idle it starts the compressor shut off/turn on dance.

So, what I seem to be concluding here is... the shroud's tolerance for air leaks is minimal or zero. Opening up the bottom for more air flow seems to help on a cooler night.

As an aside, I had a skilled tuner look at my vararam install (I won't get into the who but if you check my location you will figure it out) and he said the original gaps were not excessive so he's not sure why the issue existed in the beginning (he's installed hundreds of vararams with no AC issues) AND vararam hasn't heard of AC issues either, and they have a car that has the shroud taken off completely.

So the only thing I can also guess at is the Grand Sports are way less tolerant of this stuff. But I can say that before I did this I couldn't get any AC and now that I've plugged up even these small gaps and removed that rubber cover its running cooler and the AC works, at least at speed.

I'm still playing around and will post more. PM me if anyone wants to hear other details. I do have to bring it back into the dealer for other work so I'll have him check the high/low pressure although I would have thought he would have triple checked this since he was in that circuit for 3 or 4 days while he worked on the warranty stuff.

Best wishes to all.

 

Sbrennan, are you running headers? Yesterday, it got got over 101 on my temp gauge, and I monitored coolant temps up to 226. A/C didn't cut out once, and I have a Vararam. My problem improved after removing the fan ground from the connector and soldering it directly together. Now if I sit and let it cook, it will eventualy cut off. But I was attributing it to underhood temperatures and the fact that the uncoated headers are within a few inches of the A/C line. I was tempted to use some of that same hose insulation and some silver ducting tape to shield that line from the header heat and see if that helped.

Side note, that piece between the radiator and the air dam supposedly assists with aerodynamics and helps reduce lift in the nose. I plan to run a Katech splitter with their undertray at some point, so I am looking for different solutions (including the possibility of ditching the Vararam and going with a Killer Bee II).

Check this thread and check your connector:

http://forums.corvetteforum.com/c6-t...d-working.html

 

I think Sbrennan is on to somethig. I've been battling AC issues this summer too: http://forums.corvetteforum.com/c6-t...ep-inside.html

The not taking a charge was due to a faulty gauge set but now that it is taking a charge it will only get cold (and when I say cold I mean <60 degree vent temp) when moving over ~45 MPH. As soon as I stop the vent temps quickly rise to ~70. This is with ambient temps in the high 90's. When ambient temps get <85 degrees its not much of a problem.

The ECS instructions have you removing that front plastic thing attached to the bumper already. Obviously with all the centri kits the OEM shroud gets yanked. The ECS shroud stops air from going up and over the radiator/condenser/intercooler but not around. So I was thinking about making some baffles out of cardboard first to make sure all the air coming in the front goes through the IC, condenser and radiator. If that worked then I'd fab up some sheet metal baffles kind of like Andy's kit.

 

I believe the cover you are referring to is to prevent air from going behind the oil cooler. On a base C6, it's not there, because they don't have the large Z06 oil cooler. With the cover in place, all the air is through the grille, and thus through the oil cooler. By removing the cover, you might be creating another problem while trying to solve the original one. Have you seen an increase in oil temps since removing the cover?

 

No headers. Just stock. I will check the ground although the fan seems to run consistently without failure.

 

Interesting. I'll monitor my oil temps too. Anyone tell me what they should be running at? Or at least "not as high as..." so I know the danger point.

 

If you change your table you (highly) risk the fan plug melting from the increased amperage. You MUST replace the OEM plug with a extra heavy duty plug. You can even make your own (as I did) using aluminum 1/2" square bar and tapping screw holes (to hold wires). You would then apply HVy Duty Ring terminals to the wires.

 

So what was the outcome? Hopefully just an overpressurized AC system.

 

hey Vito, it was nice to meet you at the show. Your car is awesome!

I dont have an answer for you but if you are ever down in the central NJ area and feel like cruising, hit me up

Jon

 

Exact same problem. 402 SLP motor with a ECS Novi Intercooled SC.