Gulping Noise While sitting at Light

2000 ford explorer After it warms up sometimes I feel this thumping which shakes the car but it sounds like it is gulping for air or water does not do it all this time sometimes cold or hot and on occasion even after it is shut of it will continue for a minute or two Anybody got any ideas radiator is full,tranny is full

I think you have air in a heater hose and heater core. Check your coolant level. Check BOTH the reservoir and the RADIATOR. Only remove the cap to check the radiator when the system is cool, as in before you start it up in the morning. The next morning after it has had a chance to circulate and purge the air, check it again.

Run the front of the car up ramps or jack it up and use jack stands. Run the car to purge the air and top it off.

so an update to this I located the gulping thumping noise and it was coming from the thermostat goose neck I replaced the t-stat and had no noise for the first day but then it returned so I’m thinking it’s either the water pump or a plugged radiator any suggestions.I made sure to let it warm up to fill the system so there was no air in it and did this several times every time I opened the cap you could here it gurgling I have no leaks any where plus I put a new cap On.

It is trapped air in the cooling system. If you didn’t correctly bleed that air out after replacing the thermostat, then start there. Most likely, you have a cooling system leak somewhere that is letting air in and you will have to get that fixed. While it could be that the radiator or the water pump is the source of the leak, you have given no reason to suspect that either would be. Why do you think it is the water pump or the radiator?

Yeah…what he said. If you hear gulping there IS air in the system

have checked to make sure there are no leaks so I assumed that maybee the water pump output is not enough to pressurized the system or the radiator is plugged not allowing the system to flow properly.after searching the net I have found this to be a common problem in the explorers and that yet you have to bleed the system they feel that there is steam build up causeing the thunking or gulping noise which contracts the hoses.I guess fors had a tsb on this problem and suggest only a motorcraft water pump to correct the problem plus bleed the system several times I am going to try to bleed it for a while and see if this fixes the problem.thanks for your response.