1990 Ford Mustang 5.0 vacuum lines
3 Answers
That port is for a coolant hose that comes off the hard line of the heater hose on a stock engine. You have another issue. Check the spark plugs and wires, distributor cap and rotor, Clean the IAC and throttle body, it might be full of carbon.
Spark plugs and wires are good, we have a new distributor cap and rotor and all it’s good I’m just lost in all the vacuum lines. If I can find which ones are necessary and which ones I can cap off it would help a lot and I will check the throttle body when I can thank you
The vacuum ports for the intake are underneath the upper intake in the back. If the hoses are missing or disconnected they are quite hard to reach let alone see while the intake is on the car. If you spray a mist of alcohol in this area and the idle immediately improves, you know there's a vacuum leak. To fix the leak it may be easiest to remove the upper intake and make sure all the vacuum ports are connected or capped. If you eliminate vacuum leaks and the problem persists, start looking at the fuel filter and fuel pump.
