Engine surge????

[robxj]

Ok, so i managed to get my AC regassed on my XJ the other day, and have used it a couple of time now and have noticed that when at idle with the AC on the idle fluctuates slightly, but when driving with the AC on you can feel the whole car surge, turn the AC off and the surge go's away..... Anyone come across this before? Any ideas?

[junglejuice]

I had this on my Xr6, I was told my the mechanic that it too much gas and was causing the system to trip the over pressure switch, I don't know if the Xj has the same arrangement or not.....

[robxj]

I had this on my Xr6, I was told my the mechanic that it too much gas and was causing the system to trip the over pressure switch, I don't know if the Xj has the same arrangement or not.....

I was thinking that it could be something like to much gas, but the system dosent cool that well, like it dosent have enough gas in it! also if it was to trip the high presssure switch then it should just cut out the compressor clutch and the syatem should stop work, which is dosent.......

[amlav]

Not sure on petrol xj's but on most carby cars there is a coil on the carburator that kicks in when the AC is turned on. There is an adjusting screw on that coil lever that should be adjusted to turn the idle speed up just a tuch to compensate for power drained from the engine by AC. Otherwise small surges while driving are tipycal but are
more pronounced when engine worn or to lean ,to reach....or AC bearings worn.
Cheers, Andrei

[robxj]

Not sure on petrol xj's but on most carby cars there is a coil on the carburator that kicks in when the AC is turned on. There is an adjusting screw on that coil lever that should be adjusted to turn the idle speed up just a tuch to compensate for power drained from the engine by AC. Otherwise small surges while driving are tipycal but are
more pronounced when engine worn or to lean ,to reach....or AC bearings worn.
Cheers, Andrei


Mines a 2.5 TD....