Hesitation at moderate acceleration

[Zack]

I highly doubt its the TC.

The squeak heard at high rpm shifting is the belt...common.

[jvillerauder]

i had the exact same problem with mine. it would buck at low speeds or coasting when i tried to accelerate modestly but go away when i floored it. changed out coil on cylinder 3 and the problem went away. had the same problem with my crown vic and changed out the coils fixed it immediately. i would try the coils first definitely.

[03blackmerc]

i would say a bad Coil, my brothers MM just had the same problem. light throttle it had a slight misfire.

[Egon Spengler]

How did everyone determine which coil it was? I must have a misfiring coild, but I can't tell which one it is. I have taken each coil out one at a time and put them on a valve cover bolt and they all had spark. Any way to tell which one is the bad one?

[03blackmerc]

The dealership did a load test on each coil. i think it cost 100 bucks

[omarauder]

I would clean or replace the IAC valve. I know it controls your idle, but I've read somewhere that it is also used to "fine adjust" the fuel/air mix at higher throttle positions. Also check your throttle position sensor. The local Ford dealer parts guy says these items are classed as "wear" items.
I'm about to change mine out when I do my spring tune-up, as I've noticed some of the same symptoms.

[Joey3571]

Okay. So I've read all the post and I am still at a loss. I have replaced fuel filter and had engine scanned. NO codes. Not even a missfire. So that tells me that the coils and plugs are assumed good. Am still gonna replace the plugs this weekend. Everything I am hearing is pointing me to TC. It started happening about a month or two after a flush fill on tranny. Last thing I want to do is replace the TC and it not be the problem, but I am fed up with this thing bucking me. <- Ha! So I think I am gonna take it to the dealer and have them check it out and tell me what needs to be done. $85 to diagnose. Not bad I say. BTW, it's now surging when I stomp on it. So it will accelerate and then lull and then kick it back up.

[Joey3571]

BTW. Did I mention, no codes at all in the ECM.

[1stMerc]

Okay. So I've read all the post and I am still at a loss. I have replaced fuel filter and had engine scanned. NO codes. Not even a missfire. So that tells me that the coils and plugs are assumed good. Am still gonna replace the plugs this weekend. Everything I am hearing is pointing me to TC. It started happening about a month or two after a flush fill on tranny. Last thing I want to do is replace the TC and it not be the problem, but I am fed up with this thing bucking me. <- Ha! So I think I am gonna take it to the dealer and have them check it out and tell me what needs to be done. $85 to diagnose. Not bad I say. BTW, it's now surging when I stomp on it. So it will accelerate and then lull and then kick it back up.

Go with coil packs before fooling with the TC. Its cheaper. I had the same problem of bucking with no ill affects at idle or higher rpm. Dealt with the issue on a couple of occasions. rolling along just fine till about 45 mph or around 1500-2000 rpm then step on it and the stumble bucking starts till higher in the rpm range. Most noticable when crossing railroad tracks and getting back underway.

You can do it in your driveway. Buy one or two coils and swap one at a time. Rev engine up to 2000 gran after it is warmed up. You will be able to hear engine breaking up till you swap out the bad one.

P.s be careful of the release tab.

I didn't have any codes either and (from others in other threads) neither did they and i have a Scangauge II and an Xcal2. My coil went bad at roughly 45 and 50 k respectively. Two different cylinders. Do yourself a favor and follow the above before fooling with the TC. Remember you have two sets of windings in each coil, primary and secondary.

[03blackmerc]

id say coils or MAF. the low idle bucking is most likly coils

[justbob]

I would clean or replace the IAC valve. I know it controls your idle, but I've read somewhere that it is also used to "fine adjust" the fuel/air mix at higher throttle positions. Also check your throttle position sensor. The local Ford dealer parts guy says these items are classed as "wear" items.
I'm about to change mine out when I do my spring tune-up, as I've noticed some of the same symptoms.

+1 TPS. Easy to test also.

[Zack]

Are you sure you just aren't in 4th gear with a locked converter?


There aint ***** for power under those conditions.
Click OD off and report back.

[Joey3571]

Took it to Ford. Not TC. Recommended replacing coil. Am replacing coils with MSD's. Also replacing plugs. Am sure to have some fouled if not firing properly. Will do this along with K&N CAI since I have to take that off to get to the left bank. Will post the outcome.

[musclemerc]

If your N/A those fancy coils will do no more than the stock ones, save your money. I would say get some LFP coil connectors, some XP104 Autolite plugs, and a set of good stock coils.

[fordfnatix]

My 03 has some similar symptoms.step on the gas at 25-40 and she sputters and chokes. I have only had her for a couple of weeks and it seems to stop all together when I turn the traction control off.After reading these threads I think I have a bigger problem.