My 1998 V10 has a lot of misfires, am I doing the right thing.
 

So, the V10 in my 1998 Motorhome has been throwing random misfire codes for the last 500 miles or so. [I noticed it was running a little rough and finally threw my ODBD reader on it and found the codes.]

Mechanic says several cylinders had over 1,000 misfires. [can they even know this?]

He recommended 10 coil packs and 10 plugs. He wanted to spend about $50 per coil pack and I balked. I ended up reading on here that the Denso coil packs were a cheaper option that seemed to have great review. I also went with the motorcraft platinum plugs.

It only has 53k on it, he insisted on changing plugs due to the misfires, he said the plugs may not survive being wet from the misfires.

He wants to change all 10 coil packs, is that overkill, or is it one of those as long as you're doing them go ahead and do them all.

Lastly, what kind of labor charge is reasonable for replacing all 10 coil packs and plugs?

Oh and how bad is the plug extraction process in the 1998's? Should I be expecting him complaining about thread issues? I'm assuming with the low mileage everything is original.

I wouldn’t bother with the coils. It’s extremely unlikely that all ten went bad. Or even a few. Or even one really.

Do the plugs (Motorcraft) and boots (any brand that isn’t the cheapest). You’re correct about the Denso. I personally verified.

Does it lack power also? Maybe your catalytic converter(s) bad. It’s something we’ve all seen and talked about lately. Also known from my personal experience.

Plenty more in your post to reply; others will chime in.

Please list the codes you extracted--that's the first step.

You might also post these questions in the V10 engine sub-forum.

Without knowing more I'd highly suspect there is an issue with your crankshaft position sensor or its wiring circuit. You're also fighting against the issue of age---with your vehicle approaching 21 years old that could greatly contribute to problems such as you describe. What maintenance preventative or necessary repairs have been performed?

As a suggestion before you shell out a ton of money chasing this problem pause a short bit. I do agree the plugs are probably shot if you've continued driving this for 500 miles with misfiring cylinders. I'm not convinced the COP's are bad but we don't know what brand is currently installed.

BTW nearly any OBD-II scanner can indeed read the number of misfires with ease.

Add the requested information, post this in the V10 forums and you should receive usable answers.

Although I have a v-8 and not a v-10,I replaced all 8 plugs and coils at 200,000 mi when one went bad. Its not a job I want to do again. Oreillys sells Accell coils in an 8-pak for less than 4 coils. I have had them in 2- 5.4 vans with over 200,000 miles and still going strong.

With all due respect consider yourself extremely lucky that brand hasn't failed yet. Repeatedly in the V10 & V8 Modular Motors forums we see problems where this brand and so many other off-brand names have immediate issues or shortly after installation. We also see Motorcraft or Denso brands as being the first choice, sometimes the next choice after the cheaper brands fail.

You and I might be able to do this DIY but I get the feeling Belome isn't interested or comfortable in that same role----he has a mechanic who might do this work. For that reason alone he's better advised using a good brand, the ideal situation being he could purchase the COP's (and new boots too) and have them installed.

I've used Accel and Granatelli's both of which failed so very quickly. I now run only Motorcraft I can buy online for less than $35 each (new boots included) which is a fair price for long term quality.

Saving money is great---going the cheapest route is never the best path, IMHO anyway.

Another point of interest is my 2000 E250 w/5.4 motor is still running strong at 285K miles on 5 of the factory original COP's. Boots and plugs were replaced a few years back, my firm mileage for changing plugs of 50K has not yet been reached.

And yet another point is we don't know the COP's are bad---there's no real upside to changing them "just because....". Plugs should be changed if they're original with the 53K miles and have been running on misfires for the 500 miles. Those should be Motorcraft SP-479's which were originally installed when the van was new.

Sorry, I just got back to this.

I can't recall the codes, but i know they were 'random misfires on cylinder #x' and there were like 5 codes for 5 different cylinders.

It only has 53k miles on it, I bought it a few years ago, I'd bet everything is bone stock.

I do some wrenching, but the thought of wrenching on the V10 in a van body wasn't something I wanted to do.

Mechanic still has it, the coil packs were fairly cheap, I've spent worse money on stupider things. i just figured the labor was the worst cost of this, so why not just put new ones in.

If it is the CPS, how much of a pain is that to replace?

Sorry for the hijack, but what are coil packs? How are the different from a standard coil?

Steve

Coilpacks and coils are probably synonymous. On these fords the coil sits above the boot on each cylinder. So my V10 has 10 coilpacks.

Holy crap. Why did they move away from a single coil and a distributor?

Steve

Fewer moving parts, no distributor or plug wires to fail, hotter spark & more accurate spark timing. Ford has been doing this since the early nineties, and this is all news to you?
:-X24

I'd say your plugs are most if not all of the problem, and changing plugs and/or cops is easier on these vans than it is in the pickups IMO. The front plugs are an easy reach while standing in front of the truck and the rear 4 are are easy peasy with the doghouse removed, it's just the center ones that are more difficult but even then you don't have to climb over a fender or into the engine bay. And I wouldn't replace a cop unless it is confirmed bad, some of those originals could go another 100k before failing.

Well, my current Ford is a 1990, and it has one coil. I used to have a 1995 Mustang GT, but I don't know what it had.

5.0L,One coil.
The next model year, in 1996, the Mustangs got the 4.6L with 2 coils and the distributor went away.

Starting in 1991 the Lincoln Town Car got the 4.6L V8 with 2 coils and no distributor, then the individual COPs were phased in across the rest of the vehicle lines through the 90s.

You're not helping yourself with this sort of non-information. If you're okay spending money on guessing which fix will finally work that's okay with me---your money after all.

Best of luck with this! :-X22

I'm not usually one to just throw parts at something. However, the labor was going to be the same amount whether I replaced the coils or not. The coil packs were 22 bucks from Rock Auto so it wasn't a huge outlay of money.

A few things to note, this is in a motor home, if it sees another 20k over the next 5 years it would be amazing. My thinking is that new coil packs 'should' be good for the life of the vehicle.

Heavy duty towing is a pain in the butt. I have AAA RV but when I'm rolling in the motor home I'm going somewhere fun, the last thing I want is to break down.

As an update, I got a call from my mechanic, he is all done with it and I will be picking it up tonight. He said everything went off without a hitch and I should be good to go.

As for the not doing myself a favor with not remembering the codes, you are probably right. I pulled them last fall before it went into storage, I did some digging back then but I didn't seriously look into fixing it until I got it out of storage this spring.... my bad.

I just hope he diagnosed it correctly and I'm good to go.