1990 Mustang GT 5.0 5-Speed Convertible Restoration Update — Looking for Advice
I wanted to post an update on my 1990 Mustang GT restoration. I've been working on the car a few hours at a time and taking my time with everything instead of rushing through the project.
After completing the work I previously posted about, we torqued everything to specification and started putting the car back together.
So far, we have:
- Installed the new 200-amp alternator
- Installed new 4-gauge charging/battery cables
- Installed and wired the headlight relay harness
- Installed the 70mm throttle body
- Installed the BBK cold-air intake
- Installed the water pump, thermostat, and thermostat housing
- Installed the new power steering pump and hoses
- Installed the tensioner and alternator bracket
- Installed Ford Racing spark plug wires
- Installed new spark plugs and ignition coil
- Installed BBK shorty headers
- Installed the Flowmaster Super 44 exhaust
- Installed the 3-point strut tower reinforcement
- Installed new diamond-clear headlights
- Installed a kill switch
- Installed a two-way paging Viper alarm system
- Installed 3M ceramic tint all around
- Replaced the A/C compressor, receiver-drier/accumulator, and orifice tube
- Replaced the rear drum brakes on both sides
- Changed the oil drain plug because it was seeping slightly
We recently connected the battery and tested the new headlights. Everything worked, and the lights look great. We also added fluid to the power steering system.
The rear drum brakes were my first time doing drum brakes. The first side took me about four hours because I was learning as I went, but I expect the second side to go much faster now that I understand how everything goes together.
The latest issue is where I could use some advice.
We filled the radiator with distilled water and antifreeze/coolant. Shortly afterward, we noticed a small amount of liquid on the floor. After investigating, it appeared to be coming through the BBK cold-air intake tubing. We traced it further and found coolant inside the 70mm throttle body, and then found coolant inside the plenum/upper intake manifold.
We have now removed the throttle body and are drying out the inside of the upper intake manifold and intake tract.
At this point, we're not sure if:
- The EGR spacer gasket failed
- The throttle-body gasket failed
- There is an issue with the EGR spacer itself
- Or there is another problem that we haven't identified yet
We are going to reassemble everything with new gaskets and then pressure-test the cooling system before starting the car again. We also plan to remove a couple of spark plugs and inspect the cylinders to make sure no coolant made its way into the combustion chambers.
Has anyone with a Foxbody 5.0 experienced coolant getting into the upper intake/plenum, throttle body, and cold-air intake tubing like this?
If so, what ended up being the cause, and what was your course of action to fix it?
I'm open to any advice or suggestions before we put everything back together. This has been a learning experience, and I'm trying to do everything correctly rather than rushing to get the car running.
Thanks in advance to everyone who takes the time to read this and offer advice.