Irratic Miss - not your normal fix - experts needed!

[blazincopper]

OK I know this has been brought up a million time, but.... this one is alittle different. This is my first Lincoln (maybe my last) . It is a 2003 Lincoln LS Sport 3.9 V8. I am having a severe miss (like a dead cyclinder) that seems to get worse after the car wams up (about 10 miles or so). When you first crank it up it drives pretty good, then it goes into a death spiral. It will stat to shudder, missing while accelerating, missing while at idle. I keep getting a Coil E Primary/Secondary Circuit Malfunction. I have already replaced the coil pack, replaced the injector, and I do not see an oil around the plug - so I don't think the valve cover is leaking. I bought the car at an auction and did some research after the fact. A dealership had the car and it had been previously sugared. The dealership replaced the fuel pump, fuel filters, injectors, catalytic converters, flushed the lines, clean the tank, and a bunch of other stuff and they could still not get it running right. When I first drive the car in the morning it drives good - lots of power, so I don't think that it is a sticking valve. Any help would be appreciated. I know you guys have a ton of experience with Lincolns so I thought ya'll should have some good ideas.

Thanks

 

[NateRW21]

I wouldn't write off lincolns because of this.

If you've already replaced all of your COP's (they aren't coil packs, they are individual coils), checked the harness for damage... I really don't know what else to tell you. The fact that it warms up and starts to act funny is somewhat indicative of an engine problem.

Sounds like you have a good bit of info on this car. Hopefully you bought it for a good enough price that an engine swap won't hurt too bad.

 

[NYC LS8]

Sounds like you have a bad coil somewhere else on the motor. My car is doing the same damn thing, but I can't do sh*t until I get a check engine light to find out what cylinder it is. I believe Ford's threshold is something like 10 or 20% working before you get a CEL for a coil.

 

[joegr]

A scan tool like the one from Auto Enginuity will give you the misfire counts on each cylinder, before the check engine light comes on. Be aware, however, that the engine computer sometimes (often?) gets the cylinder wrong. It has to guess at it based on how the crankshaft is turning from instant to instant, so it is not exact. My guess is that the OP changed out the wrong coil, or didn't get all of the problem coils. Fix it soon, or those new cats will be gone.

 

[97stscaddy]

Done a compression check yet? Sugar in the tank isn't too good for the rings.

 

[chicken]

id check the connector for power and ground, b+ is constant and the ground switches. easiest way is to get a "noid light" used for checking injectors etc, just get some cheep kit and find one that fits and check for a signal it should flash while the car is running. could be a bad coil,broken power wire, broken ground signal wire, bad ground driver in pcm. another trick is to pull the codes, find out what cyl is missing then swap the coil to another hole, clear codes (disconnect battery) and see if the miss moved

 

[blazincopper]

Joegr - thanks - you got me thinking about the code begin wrong. So today I was determined to figure it out. I did a compression check on every cyclinder, spark tested every coil, and noid lighted the injectors. I found two coils not firing. Coil #1 and #4, replaced both of them on she is running great. Everything else checke dout good. There was nothing wrong with the cyclinder #5 - which is the one I keep getting the code for. Now I have to replace the sway bar bushing (I think) and it ought to be good as new. Thanks again for all the advice and ideas.