I have wondered over the years about the "Complete" Hose Kits you can buy.
Specifically, the absence of Part #PCH000330G. This is the hard black plastic return line for the throttle body heater plate. (From Throttle body to bottom of expansion tank) Parts list shows this to be fitted from 95-02, so both Bosch and Gems.
I have just replaced my alternator on the White 02 and in the process, I gently moved this pipe and had it shatter in 3 places!
Fortunately, I was not on the road, and was able to fit a 4mm rubber tube.
In hindsight, I should have noticed it's lack at the time, and done something about it however I did not. This small tube breaking could spoil our whole day!
As this part has not been included in any of the 3 kits I have purchased over the years, there are potentially many P-38s out there with degraded plastic return lines.
I pointed this out to AB, whom I bought the kits from, and they were surprised at it's lack as well.
It will be included in all future kits, I am assured.
(Just checked...It took them all of 15 min to update the parts list, and post new photos of the kit. now including this tube!)
In the meantime, they do have them in stock.
If you cannot remember ever changing this pipe, it is probably time......Do at least go give it a bend in a few places to see if it has gone brittle.