Yes....Another newb!

[1BiggHunn]

I am an owner of a 1997 Lincoln Mark VIII LSC opal/opalescent. I have had it for a few years now and it has about 193,000 on her. Just a few days ago she just started to run very badly. For instance; once the temp is up, it starts to misfire like crazy, but when it cool out side, it runs like a champ and no misfires. If any one has any input on this, it would be great, since I am wits end about this! Btw... I have changed out the cop boots, new plugs, new cam position sensor, re-built the injectors, and cleaned the m.a.s. too. It started with a misfire code on 5 then escalated into 1,5 and then the last misfire codes were 1,5,6, also the live codes said lean on 1,2, banks too. I love my Mark, but dang...she needs to give me a break.

 

[mark0101]

With that many miles, do you know if the coils have been replaced or are they still OEM coils?

 

[chargerxr]

I would check fuel pressure when it's running bad. Also change the fuel filter if it hasn't been done.

 

[1BiggHunn]

There are some of the coils that have been replaced from the prior owner I seen. I have not checked the fuel pressure when it runs bad, but I have replaced the following things though: spark plugs, coil boots, egr valve, egr solenoid, rebuilt the fuel injectors, fuel filter, replaced the air filter with a k&n, replaced the mafs, new valve covers,(the old ones were leaking oil into and on the plugs), and finally the battery and alternator. I will be checking what chargerxr and mark0101 said to check though. I did check the pcm and it was hot to the touch now, at the same time it was hot, the engine started to misfire and then rough idle then a shut down. I really don't think that the pcm is supposed to get that hot! Checked all the engine wiring and nothing was wrong. Throw some ideas at me.

 

[chargerxr]

You should be able to rest your hand on the pcm, so that's definitely a problem. Not sure if you have a bad pcm, or a bad ground going to the pcm. Bad grounds cause things to heat up. I can't remember right now where the pcm is grounded. Someone on here will know. If not I can look it up at work.