2001 S-type 4.0.
I recently replaced all 8 coils & plugs on my car. My indy tech did the work. I asked if there was any signs of oil in the plug wells and he said there was none.
After having the work done I was washing my car. I took the hose and let a slow trickle of water run down my windscreen along the width of it while the hood was open. The water ran down the screen, under the rubber seal at the bottom of it and ran directly onto the coil access covers on both sides of the engine. The majority of the water drains directly onto the engine above the coils.
Try it and you'll see..
I showed my tech the problem and he said that seal was never glued to the windscreen. It is a design flaw and the reason our coils need to be replaced so often. As well, at the bottom of the spindle for the drivers side wiper, there is a rubber seal...the water runs past that seal and drops directly onto the engine on the coil cover.
Has anyone found a good, inexpensive fix for this problem? I want to fix this before my new coils get ruined.

Cheers,
Gerry.

 

Only thing I've heard off is running a bead of silicon sealant under that bottom seal so it is glued to the screen. Also I believe they just fastened some rubber matting over the covers to deflect water off to the side of the engine.

 

This is a common fault, especially on the early cars (pre-redesign 2002.5MY), covered here before several times. It may even be in the FAQs
Yes, seal it with any sealant (even bathroom is likely OK).

However, coils still fail sooner or later as they operate in a hostile environment (heat, voltage, vibration, you name it).

 

I think I am going to have a windshield replacement shop run a bead of their urethane window sealant under the rubber seal.
While I agree coils operate in a hostile environment, I would like to offer this thought. This is my 4th Jag with 4.0 or 4.2 engines. The other ones were XK8's.
I never had to replace a single coil over many years of ownership. I know the XK8 uses different coils (Denso) where the S-type uses Ford coils. However, I think the water pouring onto them is the reason so many fail repeatedly in the older S-types.
So if anyone is having coil issues...get out the garden hose.
Cheers,
Gerry.

 

I agree with your strategy of sealing the windshield cowl area as tightly as possible. Water getting into the engine bay of these cars can cause numerous issues and tends to play havoc with the throttle body. Getting these engine bays as waterproof as we can seems to go a long way towards minimizing or eliminating some of these problems....

 

From what I understand... The "Ford" coils were the bad ones and the updated "Denso" ones are the better... That applies across all models. Remember, the rear drive Jaguars share drive train components...

Same trans, engine, etc... Even today..

Back to the water thing... The poor coil design is more likely to be the cause, not the water..

Do a search here on coils.. I know the tag color has been talked about before. I'd be real curious what color tag those failed coils have.

BTW.. This is truly a Ford issue. My Father had a Mercury Grand Marquis (2000) that ate coils... Until they finally admitted that there was a redesign and replaced all 8. After that, all was fine.. He just got rid of it in 2008.

 

Regardless of what is stated above, seal that windshield cowl as best you can. Water in the engine bay (and in the trunk as well) has been known to murder the electronics in these cars....

 

For the newbie and A.D.D. in me, and rather then getting a hose out to do the test myself, when you state seal the rubber, I looked at our Jag and just to confirm, you are talking about where the rubber is touching the bottom of the windshield? I tried to lift it up off the glass and was able to do so. Is this where to put in the sealant? When wife gets home I can put up some pictures and someone can just confirm, do it here on them. Thanks.

I can confirm one thing and have stated this on site before, I have always conditioned any rubber on the car around the doors, windows, trunk, hood and anywhere else including the plastic around the engine compartment, with some type of protectant or moisturizer as it were, doing this after a few washes of the car, and all the rubber looks new on the car and keeps its form. Never had a leak in the trunk or anywhere else for that matter, doing this. Right now, using Black Magic product I get at Auto Zone.

 

Yep, the rubber that touches the bottom of the glass is where I got mine resealed. Even taking a glass of water and pouring it on the windscreen, we could watch it run straight under the rubber seal and onto the engine. I took my car to a windshield shop. They cleaned the glass and the underside of the seal with some kind of cleaner, then they wiped on what they called "body primer". Then the guy put in a lot of urethane window sealant. He squeezed the rubber down pretty tight over the sealant then cleaned it up. He then taped the seal down & told me to leave the tape on for at least 4 hours.
We'll see what happens later when I test it, I just had it done today.
Btw, it took the guy about 1/2 hour and I gave him $60 for the job. I could have done it myself I suppose but this guy did a more professional job than I would have plus he had all the right products to do it.

Cheers.

 

and when you have to take that cowl off to access and replace different things..now what are you gonna do that its urethaned??????
Youre supposed to use hylo seal or silicone to seal the coil covers on top of the cam covers, this keeps water out and lets you continue to remove the wiper cowl for access/replacement of wiper motor, ecu, coolant resevoir etc..

 

It's all about using the correct product when you attempt to make the cowl more waterproof. You want to use something that can be removed and resealed for the times when you need to remove the cowl in order to access other things. A simple silicone bead is probably your best bet. It will channel the water away, yet it removes easily when you need to remove the cowl....

 

You know Jeffs buddy danielsaturd had a cheaper way of resolving this issue.


brutal thank you for the heads up on the hylo product!