I thought I fixed a Coolant loss issue some months ago., but it came back. My 2000 3.0 has the two coolant hoses going in and out of the intake behind the throttle body. I removed and plugged both hoses and used a vacuum pump to check the intake part of this of this system. It does not hold vacuum indicating a small enough leak to lose and consume some coolant while the engine is running. I checked a 3.0 at the salvage yard and it did hold vacuum in this system.

What am I losing by running the engine with this air preheat system bypassed? Or is it best to replace the upper half of the intake?

__________________
"Papa" Ron
2000 Extended Cab 3.0 4R44E 2wd
No mods - it's a "run to town" truck

In my opinion it will be OK, I've seen plenty blocked off. Especially being in Georgia, I bet you don't have to worry about throttle body icing.

__________________
00 XLT 4WD XCSB 4.0 my new baby
00 XLT 2WD RCSB 5.0 swap in progress.
98 XLT 4WD XCSB 4.0 dead
99 EXPO donor motor for dead one and parts for the others.
Newest Ranger Forum

ALSO pull your radiator cap. There is actually 2 functions the cap, one is the big round rubber seal that will move if there is over X amount of PSI in the system.

The other looks like a little round button in the middle. This is for as it cools and the fluid goes from pressure to vacuum it sucks coolant back out of the reservoir as necessary to top things off.

Problem is that button fails OFTEN. If you see an amount of crud underneath it will be blowing coolant in the reservoir the minute the system pressures up regardless of the pressure.

replace the cap anyway, it is cheap. One of my friends with a 99 3.0 kept losing coolant. He took it in and they charged him over 200 bucks for a flush. A couple days later problem was back. Replacing the cap cost less than 20 bucks usually and it completely cured his problem.

__________________
00 XLT 4WD XCSB 4.0 my new baby
00 XLT 2WD RCSB 5.0 swap in progress.
98 XLT 4WD XCSB 4.0 dead
99 EXPO donor motor for dead one and parts for the others.
Newest Ranger Forum

My hot water fed to the manifold has been blocked for 13 years and I've never had a problem, even in subzero weather.

x2 bypassed mine 3 years ago (Oklahoma weather isn't too awful cold for the most part)

__________________
1999 xlt 2.5l 5-speed Supercab 159k
83 diesel 2.2l na
06 F250 6.0l psd
{click for lol}