4.6L V6 intake leak

Why not go and talk to the parts people or service manager about this at the Ford dealer?

I am talking with parts folks already. They ain't sure yet.

I want to know the whole story about this issue. I hoped I would get some of the inside info here in the Ford group. It helps to know the whole truth about a problem first.

Jeff wrote:

when i installed a new engine in my t-bird i had an intake leak. after tearing it down we found they gave me the wrong gasket. after removing the intake and ripped out what i could of the gasket i took it all down to show it was the wrong part. you might try the same.

I've seen literally hundereds of these plastic intakes on 96-97 police CVs. ALOT of them failed. Our local Lincoln dealer warrantied them to 100K miles, unlimited time. I would give your local Ford and/or Lincoln dealer a call. There might be a recall or warranty you can take advantage of. I have installed probably 10 or so plastic intakes on the 96-97s. Most of them split up front near the alternator. All the intakes I got from Ford fit like a glove. GL

Scott,

The police and taxi CV's are covered by Ford but the civilian "P74's" are not. In any case, I decided to replace this part before it catastrophically failed. It was cracked on the front mounting boss but not leaking yet. So, I'm out in the cold

as far as Ford fixing it free is concerned unless I persue redress in small claims court later. It has a stress fracture and there is evidence of seepage under the thermostat area of the intake assembly. The car was brought to the dealer by the previous owner for a"drivability" issues a year ago and they fixed it with a replacement Idle Air Control. I don't know if that was a correct diagnosis and repair or not.

Meanwhile, the replacement part has caused a coolent-to-intake runner leak. Otherwise, the workmanship was faulty and I doubt that. The torque specs and torque sequence were followed by the book. There is not much to do wrong in this department I think.

I'm intrigued that the intake gasket has been quietly redsigned too, while the part number is unchanged, i.e. no revision letter change. The new gasket design did not come in the intake upgrade kit, but was at the dealer in a

12/2002 packaged part.

What I really need to know is weather these plastic manifolds need to be flat. The old one was flat and the new one varies plenty when compared against a straight rule. The new one is leaking badly. There is no evidence of gasket damage on inspection after pulling the repair part.

Just curious.. since you've changed a few of these. Is the flat rate 3-1/4 hours for this repair treating mechanics fairly? I guess the 97's don't have the crash rail and hidden bolts... an extra twenty minutes.

cowl, windshield wiper tray, windshield motor and crash rail brackets all have to come off before any real work starts on this model."

===You dont touch all that stuff on the 96 and 97.....Sounds like they built it kinda like the truck, with the engine under the dash? Are you sure about this? I've looked under the hood of the newer CV's didnt notice a big change. I know some of the rear bolts are kinda hard to get to but not

*that* hard. Aren't the coils up front, one on each side? Are you fighting the EGR tube? It can be bent up a little to alow the intake to come out. Oh, one more thing. You said it was steaming out the tailpipe. No leak outside of the engine? I dont remember ever seeing a failed CV plastic intake that leaked on the inside. That seams VERY odd now that I think of it. Your failure was between a coolant runner and an intake runner. I've never seen that happen on a '95 and up CV that I can remember. Hmmmm

I guess to keep the vehicle length down, some of the engine is tucked down under the windshield wiper pan and air cowl. You can't reach anything towards the back of the engine without removing all this stuff. They have a new "crash rail" which is a heavy steel stamping that bolts through the intake through the second right head mounting bolt to the right rear. This gem also bolts with a stud through another bracket mounted to the back of the engine. The hardware for this bracket faces the firewall. It's kind of a Hodini act to get that loose and out of the way.

Yes, the egr tube is tight to the manifold. The shop manual actually says to remove it, but it didn't seem necessary. The front of the manifold clears things by being lifted 1/2 inch or so and then brought frontward. There is about an 1-1/4" of space to play with between the manifold and the egr tube.

I looked again with bright light. The black sooty deposits in the left rear corner intake port have a pretty translucent amber color to them. It's as though the coolant washed away carbon but left varnish behind. The other intake ports have mostly a gritty black appearance. Anyway, I suspect this is where the leak was but I can't be sure.

I suppose the crash rail bolt going through all this got enough binding from other junk attached to effect the torque reading. The leak is under the crash rail assembly I think. Interesting! We set all bolts in shop manual sequence to the 20 foot pounds a read from the wrench. All bolts felt equally tight whe removing them later too.

I had read of a lot of intake failures on the 4.3L engine and on many GM's but not on the 4.6L. That is why I posted here... I didn't find anything on a Google search. That is why I went with a ford purchase. I had read many articles of GM engines sucking coolant into the engines causing major internal damage. I think it was the smaller ones at question. The only ones I found on Fords refered to the external leak except on the 4.2L Ford there were some unhappy truck owners with intake-fuel system leaks. Their sysmptoms were idendical to mine. One site described the Loud banging and clanging from the catalytic converteres and showed the gasket failure on thier 4.2L engine.

Should know more today. Do you have any comment on the pictures of the two different type intake gaskets? They both have the same Ford part number. The left on is the original construction with one ring per intake. The new one has visibly more silicon and a single bead of silicon circles all four intakes..

It interesting that the gasket design was beefed up though and yet the revision letter was not touched. So two different parts are in their system with the identical part number.

Just did a google search on "ford", "Manifold", "4.6", "failure" and came up with over 1000 hits. Blue oval news had a few good tips on this too.

BOB

No so, ALL 4.6 V8's, built within certain build periods, are covered by the recall up to seven years/100K. Contact your dealer to see if yours qualifies for the free fix. Ford didn't change anything, secretly or otherwise. The deficiency was caused by the manifold manufacture when they made a changed that did not meet Fords specs.

mike hunt

fix daily wrote:

Take your vehicle to a dealer. The warranty on the intake has been extended to 7yr/100K WOF.

mike hunt

Fix daily wrote:

this is a perfect example of the old addage, if it aint broke, don't fix it.

also, the 99 4.6 did not come with a plastic intake, it has an aluminium intake. plus the V6 is a 3.8. the 4.6 is a V8

To all the advice of if it ain't broke don't fix it. and it's already aluminum and ask for the dealer to fix free and all that... Read the original posts. Do a bit more thorough googling and you will find out that it is really not really related to where it was manufacured or which Ford

4.6L car it was in. It is a serious design fault in the cars. Only the TSB relates these erroneous thoughts. There is a class action in progress for this very defect across the entire 4.6L product line. Thunderbirds, Mustangs, CV's, Towncars. Take your pick. Every owner of this engine has a ticking time bomb.

I've looked for hours. Ford dodges the issues in their TSB's by hinting the problem is related to fleet, police and taxi use from a single assembly plant. Yep, they are important customers who network more than retail consumers.

Other analysis (look more on google) suggests that stress and shock repeatedly transfered throught he serpentine belt to the alternator which is cantalevered only at the bottom by a pair of bolts, and supported to the plastic manifold at the top suggests that this is an accident waiting to happen. My manifold already shows stress cracks on the right front mechanical support boss where 1/2 of the alternator belt stress is immediately and repeatedly placed.

It's a good thing this CV doesn't explode when parked at the side of the highway and stuck from behind at high speed. Except if you look further, there are some pretty specatular reports of this too, because of it's rear seat mounted gasoline tank. Where do you want to be diasabled with a car lacking any coolant. It's a pretty sudden and dramatic if not disabling failure mode. Parked at the side of the interstate just after the acceleration ramp is my least fav spot!

Many many folks report this manifold catastrophically failing while out of town immediately after accelerating to enter an interstate. Some report it failed right after a drag race against a rice box. Entering a highway at full throttle causes additional stress on the belts and tugs very hard on the ill supported alternator.

Most here have noticed that even a squeaking tired alternator belt stops protesting during acceleration. Think about this. Acceleration repeatedly stresses the plastic manifold which eventually fails if the car is owned long enough. The top of the alternator is readily pushed 1/8" or more with a small screw driver if it's not bolted to the manifold. This suggests that the plastic manifold is being relied upon for some serious mechanical support.

This is a design error. Ford has corrected it by swapping the alternator support runner for one fabricated from aluminum. It has little to do with the temperatures involved and has everything to do with stress fractures resulting from repeated physical movement and stress opon this plastic component. It is an unsuitable use of plastic materials in the basic design.

Since I am ill, and cannot afford to become stranded in mid-winter with a car that has no coolant and therefor no heat, I chose have the defect corrected in advance of a catastrophic failure. "If in ain't broke, don't fix it?" Think a few days beyond tomorrow. Imagine walking home five or ten miles in sub freezing temperatures, especially when walking back from the mailbox is a serious effort.

Thanks to Scott for all your help and advice. The rest of you folks, look more on google if you own the 4.6L and you will find that this part will fail... not if but when.

I think my new intake seal issue may be caused by mechanical interference of the '98 and newer "crash rail" upsetting the torque sequence. I'll soon know. This crash rail makes plug changes an expensive or time consuming task. I guess most owners never notice during their typical three years and

30,000 miles of ownership.

D'oh. could be worse. It could be GM 3.x liter series.

Falco> also, the 99 4.6 did not come with a plastic intake, it has an aluminium