I re-arranged the wires so none are touching. I have one broken 4-pin stand alone wire retainer that I need to replace. I have them routed per the illustration I have from Ford. I always do that when I change out plugs and wires. I'm still getting some intermittent low idle problems when stopping but sometimes it's firing right and there's no issue. I tried the spray down with the water bottle tonight right after I came in from work. I'm not seeing the wire light up anymore, it's just sporadic little arcs around the coil towers. More so on the front coil pack. I can't see much activity at all coming from the back coil. It appears it's all on the front. It was just replaced too this week with a warranty coil from Rockauto, not Motorcraft but Ultra-Power. I've yet to get the Motorcraft but I'm saving for 2 of them.

 

Ok good to hear things are better. Turn the engine off & try cleaning the troubled coil pack with isopropanol, let it dry, then spray it down real good with CRC Heavy Duty Silicone Spray & let that dry, then restart the engine & have another look at things after dark & let us know your findings.

 

I didn't get a chance to clean it down because it was dark when I got home. But I could tell it was missing a couple times when I stopped. I was able to properly route the intake side wires according to my Ford illustration. I'm lucky I kept the printed illustration I got one time from Ford because even in my factory Ford service manual it doesn't show proper orientation. I only had one wire routed wrong. But changing them didn't make it run smoother at stops. I double checked that the plug wires were properly connected to the coil towers. They are a little tricky to get snapped in positively no matter what brand of wires you are using. I did not check resistance of the wires when I installed them because they were new out of the box and I didn't think to do that. I also don't have a specific cylinder wire that is standing out as arcing. It's just random arcs on top of the coil. Last night I didn't remember seeing any arcing on the actual wires but I need to recheck. I did remember the last time I changed the plugs I used the Autolite Platinum gapped to the specs under the hood. I believe they were close to factory settings when purchased but I always check. I always blow around the spark plug hole area with my air blower before removing the old plugs. I check the gap, dab of antiseize and screw them in by hand first, then torque down. I always lace my wires up to the way the factory had it using the factory clips because it looks neater. The plugs probably don't even have 10,000 miles on them, maybe not even 6,000 miles. I understood what you were referring to about how the ignition system works, and how much harder it would have to work with a broken down wire or out of gap plug. With the random arcing pattern I'm seeing when I spray the coil pack down at night. Is it pretty much just a bad coil? It's not isolated to one specific coil tower and it appears to be only the front coil. Which is the Ultra-Power FD487 I got from Rock Auto this week which says for Mexico emissions I just noticed even though Ford only shows one coil for that year Ranger. Also when I sprayed it last night the idle changed too. So it's definitely affecting the way it runs.

 

Kinda sounds like the after market front coil pack case material isn't up to snuff on dielectric strength for some reason, so clean that puppy as suggested & spray it down evenly with the suggested Heavy Duty silicone spray which does have good electrical properties & see if that makes a positive difference. If it does, then you know the coil pack case isn't likely the specified material, or it's wall thickness isn't up to Fords specifications, or it has some other issue, in any case let the coil pack vendor know & see if they'll accept it as a return & give you credit.

 

I finally gave up and have the truck at the Ford dealer in for diagnosis. It still idles down to nearly a point of dying everytime you stop at a light or are low rpm crawling in traffic or a parking lot. Sometimes with a load such as the heater and coming into a stop, then a turn it actually does die. Random times it takes extra cranks to get it to start, more than it should. It always use to fire with 1 start and sometimes it still does. I did try and change the coil packs to a pair of another aftermarket brand to see if I could the arcing to stop on top of the coil packs. It did. But eventhough the spark plug wires were replaced a couple weeks ago they randomly arc in certain places of the wires. I couldn't track it down to which cylinder because I could only see it in the dark and then couldn't figure which one it was when I had the light on it. But as far as I know the wires are still arcing up towards the top over the valve cover. All are placed in the correct factory clips and routed correctly using the illustration provided from Ford. They even look like they are routed correctly, very nice and neat. The Ford dealer I wanted to go to said they don't even work on 1998 vehicles anymore and there was only one other Ford dealer close by and that's where it is. It's going to be over $150 just to diagnose it and possibly more depending on what has to be tested. If it's underrated aftermarket electrical parts causing the issue I've already got prices on a full list of new Motorcraft electrical parts.

 

Ok, good luck & I hope they put their ignition guru to work on your problem, so let us know what they find.

Did you ever try the cleaning & spray down with the heavy duty silicone, to see if it would make a difference in what was going on with the front coil pack?

EDIT: Did you ever try swapping the rear coil pack that seemed to be in better electrical condition, into the front position to see if that made any difference on how it runs?

 

There is a crack on your coil pack

 

I did the cleaning and silicone treatment and nothing changed. So then I bought another brand of aftermarket coils and tried them. Although it stopped the coil arcing the new out of the box wires still showed random arcs which were concentrated over the valve cover area or the only area I could see arcing.

 

are you using ford motorcraft wires ????????? if they are aftermarket they might cause the arcing new or not ,, these old rangers can be picky and dont like aftermarket parts ,,, put on motorcraft plug wires if you dont have them now !!!!!!!!!!!!!!!

 

Ok no luck with the Ford dealer. It says on the invoice they did an inspection but the service writer called and told me they don't have an NGS tester anymore to do any further testing. It was later in the day when I picked it up and the mechanic who checked it out had already left for the day. They told me to call tomorrow to speak to the mechanic to see what he suggests. They didn't charge me anything so I doubt they did anything major to check out the concern. So I talked to another shop where I was having a radiator for another car checked and they told me it could be a grounding issue since it actually cuts off sometimes at stops. I do have a factory Ford Ranger 2.5 wiring diagram and checked all the grounds that I found in the diagrams. I did see anything suspect, no breaks, rust, or corrosion, or broken insulation even. So just assuming the practically new wires and coils are doing what they are suppose to do but something is interfering with them, what could actually cause sporadic arcs to be visually seen in various spots across the wires? The last time I sprayed it down at night with water after replacing both coils again I no longer saw any arcing on top of the coils.

 

With the mileage on this puppy, the past history of problems on this forum, you might have more than one problem. I can't remember from the looooong up/down idle thread, but does this puppy have an auto tranny?

Have you used your ELM scan tool & FORScan to take a snapshot look at whats going missing when it stalls when coming to a stop?

 

It is an automatic. What pids would I need to watch other than the short and long fuel trim.

 

Use the ELM & FORScan to have a look for any pending or set trouble code clues to help focus your stall troubleshoot.

Seeing as how it seems to be running ok except when coming to a stop, put the torque converter & IAC on the suspect list for the engine stall.

So, seeing as how it's an auto tranny, to perform a quick check, when coming to a stop & it seems to be wanting to stall, quickly shift to "N" & see if that prevents the stall. If it does, FORScan should have found & stored a trouble code for the torque converter clutch solenoid not unlocking.

If it's fuel or spark going missing, trouble code clues for them should be stored, so let the trouble code clues focus your trouble shoot & post up All trouble code Numbers found.

 

 

So your saying it runs ok except when coming to a stop & then at idle speed it misses, sometimes stalls & there aren't any pending, or set OBD-2 codes?