misfire

[zach7]

Hello. I have a 2003 Lincoln ls with 51k miles. Id say about 3 weeks after purchasing the car I got the misfire codes. Now the only thing I did after buying the car was switch the fuel from 87 (what the previous owner was using) to 91+ which is the recommended octane. The owner used 87 for the time he had the car and never had issues. Now after reading the codes I found the misfire was coming from cylinder 2. I also got a misfire at start up (stemmed from the cylinder 2 misfire). I replaced the coil pack for cylinder 2 but not the plug because the previous owner did so before me and the car having only 51k miles i didn't see it necessary. The problem went away for about a week and is now back. I don't know if this helps but the first time this happened was after a heavy rain and it happened the second time today again after a heavy rain. Any ideas? All input is welcomed and appreciated.

 

[joegr]

Well, if you had searched...

Anyway,
1. You need cowl seals where the wiper arms go through the cowl. Yours have failed. The warranty was extended to 100K miles and 10 years on this (only for the 03 V8), but you are past the 10 years now.
2. They are COPs (Coil-On-Plug), not coil packs. Yes, they are two very different things. Yes, the auto parts guys call them the wrong thing.
3. Any time you change out a bad COP, you must change the spark plug too. Bad COP damages spark plug - damaged spark plug kills new coil - repeat. This too was covered for 100K, 10 years (on 03-05 V8s).
4. You should check and make sure that none of the plug wells have oil in them. If they do, then you need to replace the valve cover gaskets. (03 extended warranty again)
5. You won't believe me, but you really, really need to replace all the spark plugs and all the coils at the same time. Do it now, right after you replace the seals under the cowl. (If you don't, we don't want to hear about your clogged expensive catalytic converters that you have to replace soon.)

BTW, also expect to spend a thousand or so on replacing all of the plastic cooling system parts soon, unless that was recently done by the previous owner.

 

[elephantrider]

... besides what joe said, which is nail on head, don't even look at the suspension bits.

 

[RigsLS]

Well, if you had searched...

Never gets old, OP's 1st post, issue with misfiring due to coils and plug but yeah, it's not anywhere to be found on here.

Should just create a BOT that answers these type of questions, "misfire" and/or "overheating"

 

[zach7]

Well, if you had searched...

Anyway,
1. You need cowl seals where the wiper arms go through the cowl. Yours have failed. The warranty was extended to 100K miles and 10 years on this (only for the 03 V8), but you are past the 10 years now.
2. They are COPs (Coil-On-Plug), not coil packs. Yes, they are two very different things. Yes, the auto parts guys call them the wrong thing.
3. Any time you change out a bad COP, you must change the spark plug too. Bad COP damages spark plug - damaged spark plug kills new coil - repeat. This too was covered for 100K, 10 years (on 03-05 V8s).
4. You should check and make sure that none of the plug wells have oil in them. If they do, then you need to replace the valve cover gaskets. (03 extended warranty again)
5. You won't believe me, but you really, really need to replace all the spark plugs and all the coils at the same time. Do it now, right after you replace the seals under the cowl. (If you don't, we don't want to hear about your clogged expensive catalytic converters that you have to replace soon.)

BTW, also expect to spend a thousand or so on replacing all of the plastic cooling system parts soon, unless that was recently done by the previous owner.

Thanks joegr. Ive been scouring the internet for a while and I ran into a lot of what you mentioned. I just wanted to run it passed some people with more experience & knowledge than myself. So you think the COPs and plugs need replacing? This isn't an all the time thing. It usually clears up the next day if it stays dry. Could this mean the plugs and COPs could be alright and I just need to fix the leak to prevent this intermittent misfire?

 

[zach7]

Never gets old, OP's 1st post, issue with misfiring due to coils and plug but yeah, it's not anywhere to be found on here.

Should just create a BOT that answers these type of questions, "misfire" and/or "overheating"

Thank you. I did do a search hence the reason im posting.

 

[RigsLS]

It's all in the stickies which you would have found if you DID search.
Even just simply looking through the stickies or tech articles would have yielded what you were looking for.

it's been covered 10000+ times on here, coils plugs oil/water in wells, overheating, no heat.
have a look.

GLWR

oh ... and WELCOME to LVC!!!

 

[joegr]

Thanks joegr. Ive been scouring the internet for a while and I ran into a lot of what you mentioned. I just wanted to run it passed some people with more experience & knowledge than myself. So you think the COPs and plugs need replacing? This isn't an all the time thing. It usually clears up the next day if it stays dry. Could this mean the plugs and COPs could be alright and I just need to fix the leak to prevent this intermittent misfire?

It's a time thing. If either (coils and cooling system) hasn't been done in the last three or four years, you are playing with fire...

 

[FDR]

Forget about rain just causing the misfire. Water should not be getting into the ignition system. My best guess would be that a COP is marginal and the extra humidity in the air makes it too difficult to detonate. Regardless, it's still not the humidity that's the problem; it's still the COPs, plugs, probably your cowls, and chances are, your valve cover gaskets leaking oil, all working together in one clusterduck known as "the Ford AJ35 V8"

The only cars you park because it's raining are cars without hoods and cars without roofs. Everything else is fair game or malfunctioning.

 

[RigsLS]

... in one clusterduck known as "the Ford AJ35 V8"

so true.

 

[zach7]

1. You need cowl seals where the wiper arms go through the cowl. Yours have failed. The warranty was extended to 100K miles and 10 years on this (only for the 03 V8), but you are past the 10 years now.

Where can I buy these? Can I get them online?

 

[joegr]

Where can I buy these? Can I get them online?

Sure, but you'll probably do just as well or better at your local dealer. These are really low cost, so shipping (buying on-line) would be a big factor.