Brought my car to the dealership and they are telling me i have 4 bad coils....4! how the hell do 4 coils go bad, am i geting bs'd or is there actually an explanation for why 4 of my coils could hav gone bad
So the mechanic says:
- Thread starter deftsound
- Start date
RandyStinchcomb
New Member
we've had cars & trucks in our shop that have needed anywhere from 1 to 6 at a time. why did they go bad? unknown, could be age, damage, moisture or other
oh ok well i was making sure because at first i thought he was full of ****, the reason i brought it in is because ive had a misfire ongoing for about a year and i finally broke down and brought it to the dealership because im sick of screwing with it,
anyway Randy, should i replace all the boots while im at it? Also would you recommend i get motorcraft coils or can i go with a generic brand
anyway Randy, should i replace all the boots while im at it? Also would you recommend i get motorcraft coils or can i go with a generic brand
RandyStinchcomb
New Member
I would replace all the boots and I think you know where I stand on "aftermarket parts"
ok well im hoping this fixes my idle problem as well as my misfire, but i bought 4 new coils and boots
i did buy borg warner coils but they have a lifetime warrenty so why not
i did buy borg warner coils but they have a lifetime warrenty so why not
BurningRubber
10 Year Member
- Dec 6, 2004
- 1,865
- 24
- 58
Your car uses coil packs, but still has plug wires and whatnot.
The 99+ 4.6's have a coil on plug ignition. Its rediculously expensive to replace the COP's if one goes bad. Motorcraft ones are like $50-60+ each, so that x8 to replace them all... it sux.
If you had 4 coils go bad at the same time I would check to make sure they are not getting contaminated somehow. How did the boots look on the supposedly bad coils?
Maybe you had one cylinder misfiring and weak spark on three others? did they explain to you why you needed 4 coils.
Maybe you had one cylinder misfiring and weak spark on three others? did they explain to you why you needed 4 coils.
no they didnt explain that too me, i assume its because i live in galveston texas which is humid as hell as well as being an island sorrounded by saltwater
joshheat25
Member
that can do it. If he did a ignition system test he might have found a few coils that were not misfiring just yet but were weak..
You can do a ignition test where you can read the spark duration and KV's to see if a coil is weak. or if it's misfiring you can see if it's a coil by moving it to another cylinder and seeing if the misfire moves there.
One really simple test you can do to locate what cylinder has a DEAD misfire ( one that is constant) is to pull the injector connector if each cylinder one at a time to see if it changes how the engine runs. when you find the one where it does not change how the engine runs then you found the dead hole. now all you need to do is figure out what is the cause. it's either fuel,spark, compression.. those are the three things a cylinder needs to fire.
ok they gae me the wrong damn ones so i went back and got the right ones but it seems my 'misfire' is still there...
When you listen to the exhaust you can hear a tick noise every so often, its NOT an exhaust leak because i already had it checked so i thought it was a misfire
now i know its not my coils because i replaced all 4 "bad" ones but what could this be? I cleaned my tb, maf and replaced spark plugs about 6 months ago as well as replacing fuel filter
When you listen to the exhaust you can hear a tick noise every so often, its NOT an exhaust leak because i already had it checked so i thought it was a misfire
now i know its not my coils because i replaced all 4 "bad" ones but what could this be? I cleaned my tb, maf and replaced spark plugs about 6 months ago as well as replacing fuel filter
Well ....
How bad was the misfire? If you had a dead miss before you might have a plug that is fuel washed.. If thats the case then you need to remove that plug and clean or replace it..
Another thing it could be is a base engine problem such as a valve sealing issue that can be causing it.
First thing you need to do is remove all the plugs and clean them, while you are doing this check any COP boots you did not replace..
If you still have issues after that then i would go back to the dealer and have the tech use the WDS or IDS and do these tests..
1. relative compression.. this can point out what cylinder is low on compression if any..
2. injector flow tests.. this will point out a weak or clogged injector..
3. ignition test and COP stress test.. this can point out any further problems with the COP's
after these tests have been done you should have a good idea what the problem is.
hotpony
Founding Member
You can test the coils yourself if you doubt his diagnosis, don't have the specification on me but there is a continuity test they do to check the coil wire itself, should be very very low, nearly .01 (look this up first)
hotpony
Founding Member
