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I was just wondering if anybody would know Ford specs on the coil packs.
I was checking mine as I was changing plug wires, following the specs listed in my Haynes Manual. My coil pack was bad according to those new numbers. The confusing part is, I went to a Ford dealer parts dept. and checked the resistances on the new part. The new resistances were about the same.
On the secondary side the old was 13.47 K-ohm, the new was 13.6 k-ohms. The sec. range according to Haynes was 7-11.5 k-ohms, I believe. I don't have the book in front of me.
Is it bad or not? What are the symptoms of a bad coil pack?
I just had to replace mine Rich. The symptoms of my bad coil pack were obvious. Anything more than a slight application of throttle will not provide adaquate spark to the plug and the truck will run extremely bad. Do not run a bad coil pack to long, as i made that mistake. now i'm dealing with excessive carbon buildup on my cylinder heads from running too rich. I've been running full cycle engine cleaner through with every half tank and it's starting to get better and better with each half-tank full.
Thanks for the reply Tom. That is what I am trying to figure out. Is mine bad/going bad or not? The new coil pack at the dealership read just about the same on the meter as the one currently in my truck. I don't understand the discrepancy between those numbers and the specs listed in the Haynes manual which would indicate that both, mine and the new one I checked, are bad. Maybe the Haynes specs are just wrong. I was hoping one of these Ford techs might see this post and know the Ford spec.
I've been working on my truck quite a bit here lately trying to isolate a little hesitation and seemingly less power during acceleration and general preventive maint. stuff. Plugs,wires,cleaned MAF & IAC, new PCV valve, new brakes all around/new drums, changed tranny and rear diff fluids. Seems pretty much the same.
I just had to replace mine. i cranked it to leave work and it felt like I was only running on 3-4 cylinders. I it goes bad you will know something really bad is going on. Tom thanks for saying that about the carbon deposits because i just checked the throttle body an saw a lot of carbon am going to have pro fuel injoctor cleaning done, it should take the deposits of cylinder heads to.
Josh is correct regarding the symptoms of a bad coil pack. When you stomp the gas, the coil pack can't produce enough voltage to spark all the plugs quick enough and it DOES feel like the truck is running on 4 cylinders.
As far as the specs are concerned, perhaps the new one you bought is bad also, i don't know about that one.
Thanks for the replies everyone. I didn't buy the new one due to the resistances being comparable to what I already had in the truck. I'll see if I can get a number from Ford.
It is strange the way this thing is running. One day it is fine, the next it doesn't seem to want to accelerate. I can keep giving it more pedal and it acts like it has a carb w/ a sticking choke...except for not blowing a bunch of black smoke. I just hate to replace parts without knowing for sure if it is bad or not. Not getting any engine service lights or anything. Who knows...
I'll post the spec if I can get one from Ford. They are bound to have some kind technical support number.
I just had the same freakin' thing happen to me. I also had a 5 or 6 page thread going regarding it. After I replace the coil pack, plugs and wires we finally came to the conclusion that the bad coil pack, not providing enough spark, created an excess carbon build up on my cylinder heads that was creating a slight enough pre-ignition to cause the timing to be off enough so that I could not even get my truck to run faster than 75 mph on the highway at full throttle. I'm still running bottles of 10.00 carbon cleaner through my gas tank. fuel injector cleaner is not enough. I use the Valvoline full engine system cleaner which is supposed to clean the carbon out of your cylinders. I have been noticing obvious progress is engine performance as my internals are getting cleaner and cleaner. I'm sure in a few more weeks it will be running perfect again. I also had NO codes thrown during this entire process.
I haven't tried to contact Ford yet regarding a spec resistance.
I'll try the engine cleaner as well.
I was curious about the Seafoam stuff I have seen mentioned many times on this site. What does it actually clean? Will it do the same thing as the engine cleaning systems?
75MPH?....Hmmm.. That is about what I am experiencing. I can get about 85(takes it awhile) and the thing just seems like that is all it has. I was reading the thread regarding top speed. I can't get mine fast enough to get the limiter to kick in. Not anymore anyway. I can't remember 90,000 miles ago.
Some guys on this site swear by this sea foam stuff. But I asked alot of mechanics and professional race car builders about it and they said that if your cylinders are that coated with gunk, that the plugs need to be removed and to dump cleaner inside each cylinder and let it soak for a few days. Then crank the motor until all the cleaner pumps out and re-install the plugs. I got the same answer from everyone I talk to, mostly guys who race on the pro circuit.
Ive seen them before.I actually have used them.MSD,Mallory,Accel,Jacobs,and a few others make them.My vehicles ran alot better with them.And,on my hot rods they were needed.
Oh,you meant for your truck......
2007XL R/Cab,4.2 V6,auto,cruise control
The anticipation of death is worse then death itself!
Last edited by BlueOvalFitter; 07-24-2004 at 10:49 AM.
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