Now the warmer weather is here and I have been using the A/C I have noticed that my Tachometer reads low when the A/C is on. It is stable and moves with engine speed, but it is reading very low. It shows 2000rpm at 75mph where normally it should be close to 3000rpm.
I haven't seen it flicker when the compressor switches in and out but when I floored it into kickdown (which I believe does disengage the compressor) the tach jumped back to normal until I backed off.
Any ideas anybody
