I own a 2000 Dodge Grand Caravan w/3.3L V6. Last night we parked it outside for a while and we were getting ready to leave again. I turned on the engine with the AC going in park, and while I was waiting for everyone to come out which took about 5 minutes, I noticed the RPM gauge would bounce slightly and I could hear the engine rev. The revving and the RPM gauge both go hand in hand obviously but it was slight, it wasn’t like I was stepping on the gas. It did this in a continual pattern about every 10 seconds or so. The engine runs perfectly. I “think” that I have only noticed this with the AC running, but not sure. Any ideas as to what this could be? Or if it is a problem to worry about?
Engine idle problem (2000 Doge Gr Caravan)
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Compressor cycling on and off? Although every 10s is more rapid than I'd expect.
Originally Posted By: Mark72
Originally Posted By: NateDN10
Compressor cycling on and off? Although every 10s is more rapid than I'd expect.
Well, it could have been longer than 10 seconds between cycles. Does this mean the refrigerant is low?
No. The way I check mine is with a thermometer that I can stick in an outlet vent.
After the vehicle has run awhile with the A/C on and high fan you should see output temperatures in the 40 degree range.
Many people get in trouble trying to add refrigerant as they either don't purge the hoses and get air into the system or overcharge it.
Originally Posted By: NateDN10
Compressor cycling on and off? Although every 10s is more rapid than I'd expect.
Well, it could have been longer than 10 seconds between cycles. Does this mean the refrigerant is low?
No. The way I check mine is with a thermometer that I can stick in an outlet vent.
After the vehicle has run awhile with the A/C on and high fan you should see output temperatures in the 40 degree range.
Many people get in trouble trying to add refrigerant as they either don't purge the hoses and get air into the system or overcharge it.
Originally Posted By: SrDriver
Originally Posted By: Mark72
Originally Posted By: NateDN10
Compressor cycling on and off? Although every 10s is more rapid than I'd expect.
Well, it could have been longer than 10 seconds between cycles. Does this mean the refrigerant is low?
No. The way I check mine is with a thermometer that I can stick in an outlet vent.
After the vehicle has run awhile with the A/C on and high fan you should see output temperatures in the 40 degree range.
Many people get in trouble trying to add refrigerant as they either don't purge the hoses and get air into the system or overcharge it.
Ok, so if it isn't low refrigerant, then what else could the idle issue be?
Originally Posted By: Mark72
Originally Posted By: NateDN10
Compressor cycling on and off? Although every 10s is more rapid than I'd expect.
Well, it could have been longer than 10 seconds between cycles. Does this mean the refrigerant is low?
No. The way I check mine is with a thermometer that I can stick in an outlet vent.
After the vehicle has run awhile with the A/C on and high fan you should see output temperatures in the 40 degree range.
Many people get in trouble trying to add refrigerant as they either don't purge the hoses and get air into the system or overcharge it.
Ok, so if it isn't low refrigerant, then what else could the idle issue be?
Maybe remove the Idle Air Control Valve, see if it is dirty. If so, you can clean the pintle end with a rag soaked in throttle body or carb cleaner. You just want to clean the black crusty crud off the pintle. Don't drop it or handle it roughly or you will need a new one.
I agree on the IAC.
I have a 2000 town & country 3.8, and I think it's low on refrigerant as the pressure switch doesn't kick the rad fans on. But the AC still works, and it idles smooth.
Throttle position sensors are also suspect in idle problems, when they go from zero throttle to 1%, the computer says, hey, I don't have to maintain idle anymore. This won't throw a code.
I have a 2000 town & country 3.8, and I think it's low on refrigerant as the pressure switch doesn't kick the rad fans on. But the AC still works, and it idles smooth.
Throttle position sensors are also suspect in idle problems, when they go from zero throttle to 1%, the computer says, hey, I don't have to maintain idle anymore. This won't throw a code.
Sounds like you idle air motor IS working fine.
It's probably just the AC cycling.
But is there an AC charge problem? Can't tell from here!
It's probably just the AC cycling.
But is there an AC charge problem? Can't tell from here!
Not familiar with your engine set-up, but I had an idling problem with the 3.1L Beretta. It would surge between normal and rough idle.
I thought it was the IAC or coolant temp sensor, but it turned out to be a leaking fuel pressure regulator. Replaced and all is well.
I thought it was the IAC or coolant temp sensor, but it turned out to be a leaking fuel pressure regulator. Replaced and all is well.
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