someone please help... -

4.6L (1996-2004 Modular) Mustang Technical discussions on 1996-2004 4.6 Liter Modular Motors (2V and 4V) within.

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Old 10-26-2009, 07:08 PM   #1
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Join Date: Sep 2009
Location: South Carolina
Posts: 15
Default someone please help...

I've been having several problems with my car since I bought it a few months ago and I am quickly losing hope/confidence in this thing. It's an '03 and is truly in immaculate shape, at least on the outside. It has several issues though (leak from the diff and needs new clutch) which I identified early on and accepted that I would fix it when I had the money.

But another issue has got me ready to give her up. It started with what appeared to be a misfire on cyl 3 (i found it b/c the car had always had trouble starting when warm unless you prime it which I originally thought was a clogged fuel filter or bad fuel pump.) I had my local auto shop hook up a tester and found cyl 3 misfiring (but the CEL wasn't on.) I replaced the coil pack to #3 and the plug and several days later, the CEL came on and when I checked the code it was cyl#2. I then changed all the plugs, the CEL came on again this time for #2 and #3 misfiring. Then I took it to a shop and they worked with it for 3 days on and off testing everything from ignition to fuel pressure to possible radiator leak (they said they smelled a slight sweet smell from the exaust when starting it cold but then went away.)

It seems to have lost substantial power since I first replaced #3 pack and plug (I honestly don't think it was misfiring b4 I started messing with it maybe an old code that was never deleted?..but it is misfiring now!), and now it shakes on a cold start and is throwing a misfire code every couple of days!

I love this car but I am running out of money to spend on her, and thinking I might have to let it go b/c it is my daily driver. I don't know what else to consider or where else to take it besides the dealership. Does anyone think this might help solve this issue? I don't want to spend another $100 just to hear someone tell me it "might" be this or that. The shop said it could be an exhaust manifold gasket leak or even a head gasket leaking but no way to know besides just spending a rediculous amt of money to replace it and see what happens. Can anyone help me restore some confidence in this car? Or can anyone possibly tell me a mechanic that is VERY familiar with these cars in or around Charleston, SC? If not I guess this is it for me...

p.s. Sorry for such a long explantation..
birdman84 is offline   Reply With Quote
Old 10-26-2009, 07:56 PM   #2
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Join Date: May 2008
Posts: 213

How mechanically inclined are you?

If you can do the work yourself, I would first take out the plugs and see what they look like. Are any fouled? Is there coolant on any of them? Are the black and sooty or white and ashy?

This will be able to tell you a bit about what's going on in your combustion chamber.

If the plugs look good, then check the COPS. Pull the plugs out and see if you get spark. If you find a plug that doesn't spark when it should (or at all), then replace the COP.

After you've done this, you can be pretty sure that your spark system is working (yay!). However, that means the problem is something else (boo). And it also means it could be much more expensive to fix (double boo).

Since the shop was talking about smelling coolant, and you are getting random misfires every few days, I would start thinking about the head gasket. If that is ruptured (say, around cylinder 2 and 3), then it would slowly leak coolant into the chamber. This coolant buildup would make it burn coolant when starting up, as well as occasionally foul up a plug and cause it to misfire.

Unfortunately, a head gasket is not a cheap thing to replace at a shop. You have to disassemble a good portion of the top of the engine, and most shops will charge you a lot for that. Fortunately, the gasket itself is only like $30, so if you have the skills and the time you can do it yourself.

As for the other potential causes, an exhaust leak will cause a rich condition, which I suppose could potentially cause a plug to misfire if it got really, really rich. But I think you'd notice other symptoms too (gassy smell, water dripping out of the tail pipes, etc). I would be surprised if the leak is causing all of these problems.

To summarize, I would start with the plugs, then move to COPS, then decide if you want to do the head gasket.
AirBrontosaurus is offline   Reply With Quote
Old 10-28-2009, 10:42 AM   #3
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Join Date: May 2007
Location: North Carolina
Posts: 318

I agree sounds like the head gasket to me....

Its really not hard to do - follow a book - or get a buddy who knows whats going on....

I figure it this way - everything is held together by bolts ... all you have to do is find them and turn them... then put it all back together the right way - (with the heads just make sure you follow a book - those bolts have to be tightened in sequence to a certain torque)
rthouck is offline   Reply With Quote

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