Steam cleaned engine and now I have a miss!

[tbirddmnd]

I searched and coulnd't find a similar problem. This past Thursday the 17th I steam cleaned the engine with a hose, some Simple Green and Turtle Wax tire dressing to make things shiny. I have a procedure that works for my 97 Thunderbird and my wife's 01 Windstar. The engine comes out looking very clean and shiny. So I tried it on the Mark after covering the alternator with aluminum foil. Once it was clean I started it up.

It started fine but after a few seconds there was a noticeable miss. Driving it around you could tell there's a "bucking" and feels like it wants to backfire somewhere but it doesn't. There is no code either. Not knowing what to chase down and not having worked on this engine before I took it to the Lincoln-Mercury dealership down the road this past Monday. I had to drop it off until the next day. They called me and said there was a misfire on cylinder #8 and that the coil on plug boot and spark plug needed to be changed, and that there was no other cylinder that was misfiring. They quoted me a price (wait for it....) and said they could have it done later that day. I made a couple of phone calls to weigh my options and didn't get any definite directions as to what I should do so I called the dealership back and told them to go ahead and change it. They change the coil-on-plug (DG-512, Motorcraft 4L7Z-12029-AA) and one plug (Motorcraft AGSF-32W-M) and I asked them for an oil/filter change as well.

After I paid the $231.34 (yup, I was furious but no other options at the time) I picked the car up and it ran fine. I parked it in the driveway and it sat until last night. I decided to drive it while a did an errand. It started and idled smooth but after about 5 minutes the same rough-running and idle condition returned, exactly as before. Still no engine light. I got back home and parked it back in the driveway.

I really don't want to take it back to the stealership for them to charge me an astronomical amount like before. Lesson learned but I didn't have the time to do anything with it the first time. All day today I do and will again on Saturday and Sunday. When I used the water on the engine from the hose I didn't use a strong stream, I have one of those selectable nozzles and it was on "shower" for a nice gentle stream.

Any ideas? Is another coil-on-plug bad? I'm sure I can change those out but I never have. I assume they're below those covers I see. Did something else get wet that shouldn't have? It's bone-dry now.

The real reason I did this is because I belong to a local southeast Michigan Mustang club, they know I make my hoodliners and I have been making and installing them for a few of their club members, including the president and some of the board members. There was a "cruise-in" at a local restaurant and I took my family to it for dinner, while meeting up with the people I know from the club, spoke to other members about my hoodliners, and parked my car with the various years' Mustangs with the hoods raised. Many people came to the event and many looked at my Mark. There was another identical Mark at the other end with its' hood up also, it belongs to another club member. But mine had a cleaner engine! Club members know about the Cobra engines in the Marks. A couple of images are below, there were a lot more cars there than what are shown here. I drove it to the location and then back home with the miss. It wasn't far at all.

Thanks for any info so I can get this corrected!

 

[budpytko]

CORRECTION: It's the Mark engine in the Mustangs!!!!!! And don't forget it!!! LOL

.....and BTW, it's pretty easy to replave your plugs, coils and boots. Just do NOT overtorque the new plugs. Use a REAL spark plug socket, it'll keep you from breaking off the plug. Do NOT buy new boots/coils before you inspect the ones in your engine. If boots are not ripped or torn, no need to replace. Use boot grease on the boots when reinstalling.....

Do you own a scan tool? If not, have Auto Zone scan it for you and see if there is another cylinder missing.....you don't HAVE to have a CEL to have codes.

 

[tixer]

I'm with Bud. I had the exact scenario happen with my own Mark.

Is is likely that the dealership did indeed find a bad boot, and replaced it. The silicone seems to go bad over time. The problem is, you might have one more..

I have now gotten this procedure down to a science. When the miss starts, you have to be aware, but be willing to deal with it for a while. It takes longer than you would think to trigger the "check engine" light. when the light goes on, I'll pull my code-scanner out of the glove box. ($100 or so on Amazon.) and plug 'er in. Often while still driving. It will tell you specifically which one is misfiring. "misfire, cyl 5"

Head to your local auto parts store, pull the coil and inspect it. clean off any oil or moisture, and flex the boot slightly to look for cracks. In one case, I did solve the problem by giving the boot a few wraps of good quality electrical tape. it worked fine.

If you don't want to try my redneck tape fix, replace the whole coil. the last one I had to buy was about $45, if I recall correctly. I have had one fail without the boot cracking. (the coil itself failed in that case, I presume)

When in doubt, swap two coils, clear the codes, and wait for it to reappear.

The other tell-tale, is that at least on mine, I could hear the miss in the car's stereo.

I suppose better funded people would replace all eight...

You might want this, too:

 

[whiplash15]

I apologise in advance for this gripe, but if you are going to tell or instruct someone how to do any proceedure, please do it right. Many home (shade tree mechanics) are people from all walks of life that dont work on cars or aircraft for a living and only do what they think they can do for themselves or friends etc. Many times, they do more damage than they repair.
While it is fixable, you haven lived untill you screw the threads out of a head with the sparkplug in an aluminum head. It is real important to insure the engine is cool when you pull the sparkplugs. There are very few of us that know who changed the plugs last. Or what proceedure they used if any. Boots are easy to damage when disconnecting the coils. Take it easy! It is best to use a magnetic spark plug socket. I also use a 12" extention. When you have the plugs out of each cylinder inspect them for erroded or missing contacts. I use AWSF32C (the "C" means copper) Autolite spark plugs. (Less resistance, fire better, dont last as long but cost WAY less) When reinstalling, you should, (read "should as must") use Dilectric grease on both ends of the sparkplug boot and spring. To prevent thread damage in the head, it is essential that you use antisieze on the sparkplug threads. Be careful not to overtorqe the plugs. They need to be snug not over tight.
I have shopped around in my area, and have found coil boots for $3.12 each, much cheaper than the dealer. (they even have the Ford oval on them)

 

[tbirddmnd]

Thanks for the replies, I'm headed to AutoZone now to see about getting any codes read. I'll check this thread when I return and report back.

 

[tixer]

very good advice. You'll notice I said nothing about removing the plug, just the coil.

My experience with the spark plugs is that they are relatively trouble free. I have only ever changed mine once, and I am also a firm believer in anti-seize, and a cool engine.

By all means, never hesitate to slap me if I am giving bad advice. I am absolutely the "shade tree" mechanic. I am here because the pros are here. I just help where I can, and learn as much as I can.

Thanks!

 

[tbirddmnd]

Just got back from AutoZone, in addition to their scanner claiming that my oxygen sensors are bad (this happens every single time I get a code read!!), I have a misfire on cylinders 1, 6, and 8. Number 8 is the one that they changed at the stealership. I called the stealership up and spoke to the service advisor. He indicated to bring it back and he would waive the $95 fee for the diagnostic. That's what it costs! He mentioned something about a stress-test too. I'll wait to hear what the advisor says and if I can do this myself I will, this time. I just need to verify that I have to remove the bolts where it says "32 Valve V8" and the coils/plugs are there? I'm sure the plugs are in great shape, last time I was told the plug was virtually new - remember I got this car from Jeremi and it's in outstanding condition.

It only needed for me to come along and FUBAR it.

 

[tixer]

yup. those two bolts come off, the cover lifts up, and the coils are right there. They are only held in by the cover. gently un-clip the wire, and lift up the coil. easy-breezy

 

[tbirddmnd]

Thanks, on the passenger side I'm wondering if I have to remove the air inlet tube?

 

[whiplash15]

Yeah, you do.

 

[tbirddmnd]

Thanks! I'm waiting for the guy to call me back.

 

[Mad1stGen]

Gonzo, I can't read crap like this. Bring the car over, we'll sort it out.

 

[tbirddmnd]

It's at the stealership, he waived the new diagnostic fee and is charging me half off for the only remaining failing coil that they could find, cylinder #6. Hopefully that does it because I need to drive it to Grand Rapids on Sunday after Mass!

I hang my head in shame......

 

[tbirddmnd]

Ok got it back, so far so good. Drove for about 30 minutes and no signs of rough running or rough idle. If it happens again I'll change it out myself next time. The only reason I took it back to the dealership in the first place was because #8 was showing a miss according to Auto Zone and that's the one the dealership replaced the first time. They did help me out this time too on the price.

While driving I did see 2 more Marks, both on Ford Rd - a 98 CE in Cordovan driven by an older lady (she really needs to wash it, detail it and clean all the brake dust from the chrome wheels), and a 97/98 Base in Toreador Red with a younger guy behind the wheel.

Did I mention my engine bay sparkles?

 

[BadSax]

One of these things is sexier then the others...

Glad you got it fixed...

BTW, you have a PM...

 

[Mad1stGen]

FYI, the Motorcraft coils retail for $40.79, complete with boots and and springs.

They weren't probably even bad to start with, just full of moisture.

Oh well, glad you got it running on all 8

 

[tbirddmnd]

Thanks Jeremi! That's around what I paid for the whole thing, including installation, which was tossed in free of charge in my case. I paid just under $50. They wanted to ensure they did it right this time since it wasn't the first time. The guy told me they're not in the habit of doing this since they must charge labor rates.

I drove it to my temp job this morning, runs like it always has - perfect!