Help....

[Seb B.]

Okay IDK if ya'll Remember me with that 96 Marquis?? Black Beat the F up? High Miles???

Well Anyways I just got around to cleaning up the engine bay and noticed a big problem while changing the plug wires.
In the back "right hand" cylinder I found coolant in the spark plug bay area, there was also SOME dampness around the valve cover.
I am loosing coolant it seems to get really hot while the a/c is on BUT that's because the RAD fan turns off and the electrical fan is the only one to run while ac is on. No smoke other then oil once in a while from the valve stem seals, BTW how hard would it be to fix those up this car..??.. So i thought this out, I still like the car allot, and want to keep it, it's now hot "literally" at 312,000 Miles starts chipper and crisp...no grinding no broken O\D gear Just would like to know if i should be driving it or put her off to the side while I fix her up and buy the Cadillac next door?

Let me know your advice, THANKS!

[miamibob]

Do you have the original plastic intake or was it changed??

[Seb B.]

Do you have the original plastic intake or was it changed??

Its a replacement I think??? It has a plastic case BUT a metal cross-over for the coolant were the front Rad hose connects to.
But yeah the rest is plastic... I was on the road today, and the temp was above the half and went a bit up then down up again and so on...
It never got to the limits But then again A/C was not on either... After changing the wire my knocking upon acceleration went away...NO CEL....Whats next??

[miamibob]

Do a search here for photos of the original intake as opposed to the replacement to make sure what you have. If it is original it may need to be changed.

[sly]

check the heater hose and intake nipple in that area for issues. Hopefully the intake isn't cracked. No clue on the rad fan issue. Check relays and such.

[Seb B.]

check the heater hose and intake nipple in that area for issues. Hopefully the intake isn't cracked. No clue on the rad fan issue. Check relays and such.

It look like this one here exactly... so were is the intake nipple? is it that red little hoes thing or is it green and its connected to a diaphragm??

Also Im charging my camcorder so I can show you the car, and its other problems...mainly the other is a constant popping of the steering components??




I check the plug today after work and it wasn't that runny inside as before, I cleaned it up and re greased the spark boot and the engine has a straight PURR!! no uneven idle at all....so its safe to say this is effecting its performance...

ANY advise would help.

THX!!

[sly]

where the heater hose goes into the intake there on the passenger side. If you're looking for coolant leaks, you don't care about vacuum lines.

[Seb B.]

where the heater hose goes into the intake there on the passenger side. If you're looking for coolant leaks, you don't care about vacuum lines.

Okay I checked there after driving to work in the heat, I couldn't smell anything and it looked dry....but a auto parts store said It could be that when the thermostat open to fill the recovery tank it's leaking between there...and what not...UGH!

They car used to keep such good temp....

[sly]

its' not the intake then. That's good. The recovery tank is much cheaper and easier to replace. check the hose connection on the bottom of the tank as well as the cap as a bad cap will leak too and that's even easier to replace.

[Seb B.]

OKay. I will take some pics today. And see if those help.

Any other advise?

[sly]

first you have to find the leak. once you know what is actually leaking, you can proceed with fixing it. Next time you drive it and get it up to temp, pop the hood and see if you can find the leak.

[Seb B.]

first you have to find the leak. once you know what is actually leaking, you can proceed with fixing it. Next time you drive it and get it up to temp, pop the hood and see if you can find the leak.

I still can't find the leak....But I found another problem...While driving the Hell out of it pressing the gas pedal swerving left to right J turns, 180's...and what not...I found that when the engine is warmed up the car under WOT makes a loud knocking or detonation sound....and you can feel the loss of power as the RPMS get higher. As the RPMS get higher the knocking gets louder and more consistent.

It sounds like its first coming from one side of the engine bay then as the RPMS rise it sounds as if its coming from the whole engine....

So any advice?

[sly]

Don't hoon it... at least until you sort the leak. It could be a head gasket or intake gasket at this point. Hooning it will just make it blow up faster.

Pull the plugs and check for whitish crap build up. Good indicator that you may have a coolant leak internally in that area.

[Bobcat]

Broken plastic intake? It's common on 4.6s, I know on whale bodies it is, I'd partially assume so with aeros. Well if that's it..

The back of the plastic intake cracks and leaks coolant, solve the problem by finding a /04+?/ (Believe this is the year they solved the problem, a quick Internet search would tell.) in a junkyard and take the intake; replacing yours.

Or, alternatively order a new one. Stay away from Dorman brand made ones, I've heard many horror stories of them destroying power.

[gadget73]

Overheating will make it tend to detonate. Make sure the fan clutch isn't shot, and make sure its not low on coolant. The wrong plugs will do it too. They like stock replacement Motorshaft plugs. Whatever the label under the hood says to use is the kind to buy. If they are questionably ancient, it may be worth changing them.