sowaidi

iTrader: (5)

Hi respected members,
All help would be appreciated. Its over a 100 degrees here almost all day long. I thought my AC compressor was almost done so I replaced it but it turned out that the ac compressor doesn't stay on when I'm not moving so its not cold. It goes on and off when I'm parked but goes on when I'm driving. The wiring looks ok and I had replaced the AC compressor, Orific tube, accumulator and 2 switches but its still the same. 2 shops couldn't figure out the problem and one shop says it might be from the PCM. It was tuned in winter so I can't say if the issue existed since then. This issue is on my 04 Silverado with the Ls7

Please help your brother get cold air.
Thanks

onyx_rock

iTrader: (8)

My TA does that too with the cam i have now. i believe it is due to the idle RPM. I can hear mine cycling on an off. Give it a little pedal and it runs just fine. Try raising your idle and it will probably solve your problem.

jimmyblue

iTrader: (11)

"Stall Saver strategy" will cut out the compressor if
"unstable idle" is detected. That is a common result
of cam swaps and needs finicky tuning of the idle
mixture (air mass error) and for me, some fiddling of
the idle RPM loop P/I/D settings (control loop stability
stuff). Rich idle mixture destabilizes idle generally.

Now, too, the compressor will cycle against the high
side pressure limit and at idle you have squat for
cooling airflow (and just a bit, when the fans run).
You could just be stacking up refrigerant before the
condenser. Are your fans running when A/C is selected?
When's the last time you blew all the debris out of
the condenser and radiator fins?

RezinTexas

my 01 burb with cammed stroker motor does the same thing. I'm in for answers on this one.

S10xGN

iTrader: (11)

Have you done a pressure survey? Low freon makes a compressor pull down to the low pressure switch setting, cut-off, then restart when the LP switch is satisfied.

sowaidi

iTrader: (5)

Thanks for all the advice. I don't know how to perform the pressure test but I'm assuming the shop has done it. The AC was serviced recently, got the condenser clean but not the radiator. It is speed density tuned FYI if it makes a difference. It only turns off when its idling not driving, so would the fan really be an issue?. I'll put an auxiliary fan between the grille and radiator that turn out with the AC. The shops say tuning and the tuner says its not the shop but the wiring or electronic parts.

jimmyblue

iTrader: (11)

Well, ask your tuner to turn off "stall saver strategy enabled"
(in the idle section) and see if that fixes the behavior. If so
then it -is- the tune, specifically the quality of idle stability.

sowaidi

iTrader: (5)

Thanks guys but I tried everything except the "stall saver strategy" since I didn't get a hold of the tuner and he said before it wasn't a tuning issue. Its even getting worse than before. It used to stay on when I'm driving but its not right now and shuts off and turns on randomly. Please guys its so hot right now and this 7.0 vehicle is useless at the moment.