Hello everyone, I have a 1999 Lincoln town car with 93,000 miles on it. I recently heard that the engines in these cars (4.6l v8 2 valve) have a weak intake manifold that is prone to cracking as it is plastic. Currently the intake manifold on my Lincoln has no cracks that I am aware of and runs perfectly fine. Should I replace the intake manifold with an aluminum one out of precaution, or just leave it alone as it currently functioning fine? Thanks for any help you can give me.
If you can find one and you plan on keeping the vehicle for a long time, I would.
If it was my car and I was planning to keep it a very long time I'd probably replace it with the aluminum part so I wouldn't have to worry about the garbage plastic manifold cracking while on the road. (If original the plastic part is already 23 years old and on borrowed time.)
You are exactly right. I would wait until it fails to replace it unless you depend on the car for daily transpo. You could do it now because it probably won't last forever.
I just did one this past summer on a 2001 4.6 with 155k miles. It had a small crack below the thermostat housing and leaked coolant. On the older than 2000 engines there is a heater tube that runs under the intake manifold that has to be replaced as well. The new manifolds are slightly larger and the new tube has a different shape to accommodate. There are a few Youtube vids on how to do the job.
IMO
do it now instead of waiting for it to fail and you lose all your coolant
The new aluminum manifolds are available at places like Summit Racing. Be prepared to spend $7-900+ for parts only.
