Have a 1996 Honda Accord that had a tune up ( new plugs, wires etc). also had leak in a radiator hose fixed. About a month later, engine started to over heat. Fluid in radiator was very low, but no phsical leak. Filled it up and in 3 days radiator is low again. This time I noticed a soft brown buildup around the radiator cap.I checked the oil filler cap to see if the underside was carmel color ( head gasket leak), but cap was clean. Now, it is running rough and will not idle when I come to a stop. Can’t figure out what is going on !
Sounds like a head gasket leak. You need to get it checked. Leak down test and hydrocarbon test should verify it quickly.
Pull the oil dipstick out and check if the oil is contaminated with coolant.
Tester
I agree with @knfenimore. Maybe drive it to the shop if it isn’t far but stop using the car until you get it checked.
Agree with knfenimore.