2000 Ls V8 Misfiring
jphelps1976
04-28-2004, 06:36 PM
Engine seems to be misfiring, idles rough, and upon acceleration it gets real jerky. 95% sure my problem is a misfire. I took a brief look under the hood and then just closed it back. I always do my own repairs on my truck, but I didn't like what I saw under the hood. Not near enough space to see what is going on.
I'm going to tackle the project this weekend. My guess is either a fouled plug(s) or a bad coil. Any suggestions from anyone who has had a similar problem would be appreciated. I'm a rookie level mechanic, but I refuse to pay the dealer prices for repairs, so I welcome all suggestions on the easiest way to diagnose and repair.
thanks.
I'm going to tackle the project this weekend. My guess is either a fouled plug(s) or a bad coil. Any suggestions from anyone who has had a similar problem would be appreciated. I'm a rookie level mechanic, but I refuse to pay the dealer prices for repairs, so I welcome all suggestions on the easiest way to diagnose and repair.
thanks.
CGGorman
04-29-2004, 10:02 AM
This a very common problem with the early V8's. I'll bet my hat you have a leaking valve cover gasket that is soaking your coil(s) in oil which, in turn, is causing coil failure and/or misfire. I'll also bet it's the passenger side. When you pull the covers, check for oil in the plug wells. If there's any oil in there, you got a leak.
Mine's leaking, but not bad enough to worry about yet.
Mine's leaking, but not bad enough to worry about yet.
jphelps1976
04-29-2004, 12:18 PM
Thanks for the info. If the leak isn't too bad, can you just clean the plug and the well to buy some time? If so, how do you clean it? Just blow air through there from a compressor?? Thanks again
CGGorman
04-29-2004, 01:56 PM
I s'pose it depends on whether the coil is scrap or not. You could blow it out if you cover the hole with a towel to catch all the spatter. It might be just as well to poke a towel down in there and soak it up. I've never had the cover off mine since I've got a 100K mile warranty and I;ve only got 75K on the clock. I only know the deal 'cause of the folks in the club.
jphelps1976
04-29-2004, 02:03 PM
Thanks for the info CG!
I will follow your advise and see what I can find out. I've done a little more research and your opinion seems to be a common theme. Doesn't sound like it will get too technical, I'm just hoping I have a bad coil or plug, and not the gasket issue. Thanks again
I will follow your advise and see what I can find out. I've done a little more research and your opinion seems to be a common theme. Doesn't sound like it will get too technical, I'm just hoping I have a bad coil or plug, and not the gasket issue. Thanks again
MercCougarXR7
05-16-2004, 05:32 PM
I've had the problem you've described JP.
I'm cheap too, don't like paying my dealers extortionist rates for simple fixes. Anything major and my mechanic (brother who works for beer :D) takes care of things.
Your problem could be deeper than a coil, my computer actually went 'bad' and wouldn't send a firing signal to one of the cylinders. Wasn't long after that was fixed (under Ford's 5 year warrenty on computers) that the problem started again. We traced that to a misfiring coil again, but this time it was because of what Chris described - water/oil/dust/crap getting under the coil pack cover, and down into the holes where the plugs are.
It's very tight, but if my big hands can work in there, so can you. It's theory it's a simple job, but in practice you'll lose skin from your knuckles.
If your check engine light has come on, get it read as that may help pinpoint which cylinder to focus your attention on. Otherwise just pull all the coils and spark plugs (change them while you're at it).
Mine was fixed simply by cleaning the coil that was wet/rusting with brake cleaner, and sanding the contact points between the spring in the coil, and the top of the spark plug. The well was hosed down with brake cleaner too, everything was reassembled, the battery was disconnected for about 1/2 hour to clear all codes.
Problem solved.
Good luck to you, hope my experience helps you - and let us know how things go!
I'm cheap too, don't like paying my dealers extortionist rates for simple fixes. Anything major and my mechanic (brother who works for beer :D) takes care of things.
Your problem could be deeper than a coil, my computer actually went 'bad' and wouldn't send a firing signal to one of the cylinders. Wasn't long after that was fixed (under Ford's 5 year warrenty on computers) that the problem started again. We traced that to a misfiring coil again, but this time it was because of what Chris described - water/oil/dust/crap getting under the coil pack cover, and down into the holes where the plugs are.
It's very tight, but if my big hands can work in there, so can you. It's theory it's a simple job, but in practice you'll lose skin from your knuckles.
If your check engine light has come on, get it read as that may help pinpoint which cylinder to focus your attention on. Otherwise just pull all the coils and spark plugs (change them while you're at it).
Mine was fixed simply by cleaning the coil that was wet/rusting with brake cleaner, and sanding the contact points between the spring in the coil, and the top of the spark plug. The well was hosed down with brake cleaner too, everything was reassembled, the battery was disconnected for about 1/2 hour to clear all codes.
Problem solved.
Good luck to you, hope my experience helps you - and let us know how things go!
philly4
07-28-2004, 09:22 PM
I had the exact same problem. It was a ba coil #4, I replaced it along with fuel filter and new bosch platinum 2 plugs and let me tell you my car runs as strong as new. Spent a total of about $110 and its well worth it.
philly4
07-28-2004, 09:29 PM
I had the exact same problem. It was a ba coil #4, I replaced it along with fuel filter and new bosch platinum 2 plugs and let me tell you my car runs as strong as new. Spent a total of about $110 and its well worth it.
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