Hey guys. I have a 2004 Escape XLT 3.0l V6 4X4. ~190k MI. I have noticed sometimes that it surges when driving. It does not happen all the time. I have read over and over on the forum it probably is a Coil Pack.. so I am wondering if there is an easy way to diagnose which one (not taking to a dealer) it is. I know I do need to change the plugs, since I am sure they have not been in a while.. but I want to make sure I have all the tools I need before doing the whole thing. I have already watched the vids on how to change the back plugs.. etc (thanks to this forum!) and just want to have to do it once. I want to get this done before it starts raining and snowing.. LOL

I got this Escape from a guy who bought it from a trade-in at a dealer. The car was originally a California Fleet, then one owner, the guy bought it from the dealer to resell.. and I bought it from him. I have the records on it (which is nice). Since I have had it, I have only had to change the usual basics, and then of course had to put in an alternator a few months ago (usually do all my work, but after reading the pain it was to put it in.. just paid a mechanic).

It has been a really awesome vehicle, and wish to keep it for a very long time (just wish it was a hybrid). Living where I do, you need to have a 4X4 in the winter. BTW, how do Escapes run in the snow/ice?

Thanks, and love this forum!

 

sometimes the throttle cable hangs up and causes surging.

 

happens when hot correct? or following a hot soak? More often up a hil high gear feathering throttle?

 

I would expect a failing coil to just fail unless it is arcing through the boots. That {arcing} can happen when the gap is too large, as in spark plugs are worn too much. If they are old, do the standard maintenance before trying to figure out other possible causes. At least I would. If you have the records, check to see if the plugs have been replaced. Two things can happen if you procrastinate: 1) the ECM can get fried due to, I think, back EMF from the coil, and 2) the catalytic converter can get ruined because of overheat from unburned fuel being fed into it.
Plugs are cheap, upper gaskets are cheap, and you'll get better mpg if you do the work. If you do, inspect the boots on the end of the coil packs for evidence of arcing. If they are damaged, spend the few bucks to replace at least the ones that are arced.
Then check for other causes of surging.
tom

 

the reason I ask is the coil will fail internally when hot then not be able to provide the kv to jump the spark plug gap and it will be a dead miss surge feeling. Coils are so common on ford its not even funny. When cars come in shop for misfires its the coil 95% of the time. ford plugs rarely fail. Everyone always chases the plugs, but us ford tech know better.

 

Can't disagree, but it seems that the volts will jump to ground wherever it is the lowest potential. If that is through the boots, you'll get the miss also, but more likely intermittent. I've had a distributor pickup coil that was sensitive to temperature. It would work fine when cold, but a particular temperature, soak in a parking lot perhaps, made open up. No more sparky.... until it cooled. Once it became that definite, it was replaced, and I did not like that job.
I would think that there is less work for the coil to do if the plug gaps are within tolerance, rather than too wide because of poor maintenance. Wear the plugs out by 100k, and you have worked the coils a bit harder than if you replaced or re-gapped the plugs when their gap was too large. My plugs were over the gap limit before 100k miles, so they were replaced. Perhaps prophylactic, but I did not want to cook the converters through inattention.
tom

 

Can't disagree, but it seems that the volts will jump to ground wherever it is the lowest potential. If that is through the boots, you'll get the miss also, but more likely intermittent. I've had a distributor pickup coil that was sensitive to temperature. It would work fine when cold, but a particular temperature, soak in a parking lot perhaps, made open up. No more sparky.... until it cooled. Once it became that definite, it was replaced, and I did not like that job.
I would think that there is less work for the coil to do if the plug gaps are within tolerance, rather than too wide because of poor maintenance. Wear the plugs out by 100k, and you have worked the coils a bit harder than if you replaced or re-gapped the plugs when their gap was too large. My plugs were over the gap limit before 100k miles, so they were replaced. Perhaps prophylactic, but I did not want to cook the converters through inattention.
tom

 

Hi everyone
Couple of things - If you had any sort of a misfire going on then you would get an engine code for it - even if it just said "random misfire" for the code. The system reads many sensors all the time and can usually see very slight changes. One of my trucks gives a code for misfire or even O2 sensor if I am towing a heavy load because truck does not act like normal with so much load on it, and computer knows it is not performing as it usually does. I did not go pull manual but are you sure this truck is not a full electronic throttle? (No actual cable from pedal) I have seen many of these in all types of vehicles that surge or have little response in certain cases (like reverse). I would suggest you find a person that has a good computer analyzer that does detailed "real time" readings and see what it shows when you are driving at a good steady speed. If you see things like throttle sensor % reading going up and down or fuel pressure when you are holding pedal very steady then you have a fuel pressure or throttle sensor issue. With the miles on truck Tom's idea of CAT failing is also very possible. My Explorer did many strange things and became very sluggish until new CAT put on (188k now) and then it was back to roaring down the road. But any major glitch in the firing, vac loss, or other issue would cause light for sure. When I mention above about an analyzer I do not mean cheap code reader but on that topic, have you actually insured no codes showing - even pending code? Had lady bring us a 2005 Freestar that was running real rough and found seller had disabled engine light before selling to her.

 

Yes if the boots have cracks or splits in them they arc the ground i.e. plug well in head quite often and will feel like a dead miss more than intermittent. Also on the plugs yes wider gap from worn plus will require a higher kv to jump. Also from what I have seen in the past on cars that come in is platinum tip plugs or not is right around 60-70k miles on them and their gap is way out of spec already.

 

loco, I bet a donut you've done more than me, so I believe that the '100k before tuneup' marketing is not a help to the customer. Wait long enough, and you get to do a major tuneup, as in major lightening of the wallet. At least that's my thoughts.
I did work on a Honda with plugs in the wells, and the O-rings got cooked over time and allowed oil to seep into the wells. Did a number on the boots, and caused intermittent arcing that was only cured by replacing the almost new plug wires. Was not a dead miss, but intermittent. I had removed the cam cover, rocker assemblies, replaced the seals, PBT, adjusted the valves {16!}, put the cover on, plugs, wires, fired it up and was fine. A couple days later, got the thing rolling up the drive again. Intermittent. New wires, and all was well.

tom

 

Have it code read.When my 1 coil went it had a miss while on the highway.It had a pending code for the coil pack.