Well, about 2 years ago I posted a thread asking about an innocent looking coolant leak. Here's my original thread...

https://www.ford-trucks.com/forums/1...take-leak.html

One thing lead to another and I never got around to doing anything about it and it finally bit me two weeks ago. Pulling a hill and the truck started misfiring. Never did get a check engine light but I got it home and put a scanner on it and saw a "pending code" P0303 -- misfire cylinder 3.

I pulled the #3 COP and noticed the bottom of the boot was wet. Further inspection revealed ~1/2" of dark liquid in the bottom of the spark plug well. I thought oil at first but it smells more like coolant.

I decided to pull #1 and #2 and they were both wet as well. #1 definitely had coolant in it as it still looked slightly green, probably ~1" deep in the plug well. It was so bad that the spring for #1 was corroded in half. I don't know how it was still working.

I pulled #4 and it was dry. I also pulled #5 and it was dry.

So, it looks like I'm going to be replacing the intake gaskets this spring. I think I'll replace the intake as well since I've read they tend to crack. Trying to decide if I should go with the Dorman unit or pony up for a Motorcraft one..? Truck has 120k miles on it now.

Haven't done a writeup in a long time so I'll do one on this so that will be fun.

Moral of the story... don't ignore intake manifold coolant leaks! At least not for two years

 

A few pics...

Here's what the COP looked like on #3



And, here's what the spring looked like in the COP for #1

 

Haven't seen ya in a while Jason, that sucks with the coolant leak and with only 120,000 miles. isn't there a hose that runs under the intake that is known to leak antifreeze on these motors? Looking forward to your write up on fixing the issue. As far as which one I have heard good things about the Dorman manifold, I usually try to stay Ford but if the price is drastically different I would probably go with the Dorman..

 

Hey Chris. Yeah, its been a busy year and I haven't been on here much. Bought a house back in March so that's kept me off the streets. Then we had our 2nd child 3 weeks ago so I haven't spent as much time as usual on here, or on my truck.

From what I've seen, the Dorman is around $160 and the Motorcrafts are mostly in the $350ish range.

 

I know what you mean life gets in the way of all our fun.. After seeing your thread from a couple years ago I see its not the hose but the manifold. I guess for the difference in price I would go with the Dorman seeing as the Motorcraft one only made it about 100,000 miles...Oh and congrats on the Baby

 

At rockauto.com, the Dorman intake is $170.89, gaskets included.

 

Avoid Dorman at all costs. The airflow is restricted heavily in the cheap intakes. There have been lots of issues in the Crown Vic 4.6l world about the terrible quality. I myself experienced it. Spend the extra coin and get a Motorcraft intake. Also the cheap Dorman gaskets don't hold up. You get what you pay for.

 

I have had no experience with the Dorman but it sounds like Kdr has so I guess I would spend the money on the motorcraft then..

 

my plan was to go with Dorman. Although my intake manifold is not leaking my heater hose that runs under it is. With the complete tear down and a hundred twenty thousand miles just like you I'm replacing the intake manifold as a PM. While I'm in there I plan to do plugs boots and any Other Hoses that are Inaccessible with the intake on. I've checked out your write ups in the past they have been very helpful to me. When are you planning to do this? I'm holding off until May 1st maybe I'll use another one of your write ups if its done. Good luck

 

Thanks! Yeah, its been a super busy year! Getting back into wrenching by necessity though

 

Thanks for the info! I was just studying them earlier and noticed you have to buy a specific gasket set for that intake. Thought that was kinda odd. I tend to lean toward OEM stuff as long as the price isn't out of hand. Sounds like the extra cost might be worth it this time!

 

Sounds alot like my plan! I'm going to replace my plugs since they'll be so much easier to access. Going to replace the coils as well since quite a few of mine have been soaked. Good idea on replacing all the hoses and such that are usually hidden.

My hope is that my leak is slow enough that it can wait until late March or early April. If the leak is bad though I might have to do it sooner. I'm going to pull some COPs again this weekend to see how much coolant has made its way back into the plug wells.

 

So I drove my truck to work all week totaling around 40 miles with quite a bit of idling to defrost in the morning. This afternoon I pulled COPs 1, 2, & 3. I could see a few droplets of coolant on the top of the boots but no puddles in the plug wells.

So, it looks like my leak is fairly slow and I think since I put new boots on those three coils it should keep the moisture out until I can fix it for real in a few months.

 

Good deal, summer will be here soon, always easier to fix when its warm

 

Definitely! Looking forward to warm weather again. Supposed to get below zero here again this week they say