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Joey3571
04-24-2010, 07:56 AM
Here's one for you folks: when driving my black betty at low speeds or highway speeds, if I accelerate moderately, then I get some severe hesitation. If I punch the gas, she buckles down and screams like normal. My question to you folks is, what the heck is it. Air filter, fuel filter or something more serious?

Thanks all.

dohc324ci
04-24-2010, 07:58 AM
how many miles with the current fuel filter? what mods if any do you have. how many miles on your car?

Fuel filter is a 10 min swap out and inexpensive.

Joey3571
04-24-2010, 02:44 PM
94K miles. I was thinking fuel filter. No mods. All stock. But wanted to get to the point if someone knew of something else it could be.

Bobmiddle
04-24-2010, 03:09 PM
I think I am having the simular issue. I would describe it as a bucking. I happens under slight acceleration when the RPMs are low and the trans does not down shift? I want to say it is the torque converter in my case because it only happens under the 2800rpm stall speed of the stock converter.
In my case i do not think it is fuel related issue due no hesitation from the motor.

Give more info on your issue to get more Ideas on what it is.

And if I am way off on this please chime in????


My mm is almost stock too and 90k on the odo.

Egon Spengler
04-24-2010, 03:55 PM
Buy some MAF cleaner and spray down the MAF and IAC censors.
Replace the Fuel Filter.
Also, maybe plugs? or coils? Have you replaced the plugs at all? Did mine at 100k

1stMerc
04-24-2010, 03:56 PM
Have you ever had to replace coils. If not, time to check them.

darkvader1
04-24-2010, 06:47 PM
i had this problem an it was a coil pack on number #3 minds bucked at between 30 an 40 mph.

Black_Out
04-24-2010, 08:13 PM
Is it a bucking sensation? Or is it pretty much like from 40-60mph there is no power there?

My 04 vic does that, where you get to about 40mph and it just drones and there is really no power there unless you give it alot of gas.

Joey3571
04-26-2010, 04:27 PM
I'm starting to think that I agree with BobMiddle. It only happens under 2800 RPM. Usually around 2K. In the past I have also noticed a squeak when shifting at very high RPM which may be another symptom of the torque converter. I am changing the fuel filter tomorrow. If that does not fix the issue, then I will replace the pluges and clean the MAF or replace with a K&N CAI kit. If that doesn't fix it, then it's off to get a new torque converter.

Thanks for the info folks, but it appears that since the issue does not present it self when in idle, that it is something with the TC.

Bobmiddle
04-26-2010, 04:45 PM
I have not come up with a true answer waiting to have some $$ to fix before I take it in. Just my thoughts with my issue. Anyone eles have experience with a TC going out?????? It would help me too.

LeoVampire
04-26-2010, 04:49 PM
I have not come up with a true answer waiting to have some $$ to fix before I take it in. Just my thoughts with my issue. Anyone eles have experience with a TC going out?????? It would help me too.

It's kind of unusual for a stall torque to go bad unless they were bad before they were put in ans show their ugly head right away. They are usualy built well enough to hold up. But if somthing gets inside of them from the tranny that is a differnt story.

Loss of pressure from a cloged tranny filter on the other hand could be an issue.

1stMerc
04-26-2010, 05:46 PM
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.

JimmyXR7
04-27-2010, 06:34 AM
Here's one for you folks: when driving my black betty at low speeds or highway speeds, if I accelerate moderately, then I get some severe hesitation. If I punch the gas, she buckles down and screams like normal. My question to you folks is, what the heck is it. Air filter, fuel filter or something more serious?

Thanks all.

Over the years I have had this problem with many cars as I buy the cheap gas. Gas in California is $3.399 at my local name brand station.
So I would spray down the carb (immediate fix) or put fuel additive in the gas tank (wait and see).

With injectors on the Marauder, your choice is limited to adding injector cleaner to the gas tank. The bottle of injector cleaner is a lot less cost than a mechanic.

Tell me in a week when you know the results.

Jim

Bobmiddle
04-27-2010, 10:41 AM
It's kind of unusual for a stall torque to go bad unless they were bad before they were put in ans show their ugly head right away. They are usualy built well enough to hold up. But if somthing gets inside of them from the tranny that is a differnt story.

Loss of pressure from a cloged tranny filter on the other hand could be an issue.
It all started to kappen a few weeks after a tranny flush. I have allready done a seafoam treatment. So for my situation the TC is sounding more and more likley

LeoVampire
04-27-2010, 11:14 AM
It all started to kappen a few weeks after a tranny flush. I have allready done a seafoam treatment. So for my situation the TC is sounding more and more likley


Key word is a flush!

They never change out the tranny filter any more and they do get cloged with clutch material over time and can reduce fluid pressure.

Zack
04-27-2010, 11:52 AM
I highly doubt its the TC.

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

jvillerauder
05-04-2010, 08:41 AM
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
05-04-2010, 11:52 AM
i would say a bad Coil, my brothers MM just had the same problem. light throttle it had a slight misfire.

Egon Spengler
05-04-2010, 12:00 PM
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
05-04-2010, 12:09 PM
The dealership did a load test on each coil. i think it cost 100 bucks

omarauder
05-04-2010, 12:36 PM
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
05-27-2010, 11:46 AM
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
05-27-2010, 12:02 PM
BTW. Did I mention, no codes at all in the ECM.

1stMerc
05-27-2010, 04:36 PM
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
05-28-2010, 09:45 AM
id say coils or MAF. the low idle bucking is most likly coils

justbob
05-28-2010, 10:48 AM
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
05-28-2010, 10:59 AM
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
06-02-2010, 09:02 AM
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
06-02-2010, 09:39 AM
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
06-03-2010, 09:09 AM
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.

281MERC
06-03-2010, 08:39 PM
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.
I dont think the MSD coils cost any more than the stock set.

Reek09
06-04-2010, 04:05 AM
Must be the season for this. My MM is having a misfire prob also. I think I need to change the COPS though. It misfires at idle I feel a slight shake and shudder when sitting at a light. When I accelerate it chokes a little but then it goes away as I give it more gas. I took out all the coils and cleaned the springs and put dielectric grease on them and still the same thing. So I'm gonna replace the COPS and hope it that. Anybody know where I can get a good deal on the coils in the DC area?

musclemerc
06-04-2010, 04:53 AM
Well since your bent on spending cash why not go with the Granatelli's? Atleast then you get the nice COP connectors. The MSD's dont have that feature.



I dont think the MSD coils cost any more than the stock set.

The Great
06-04-2010, 05:30 AM
I have the same problem. Next week I'm supposed to be taking it to the dealer since it's still under warranty and hopefully they'll find what's going on.

Joey3571
06-06-2010, 09:42 AM
The MSD's (part number 82448) are only $372 from Summit Racing. I have not received mine yet, but should in the next week. I plan to replace them this coming weekend as long as my K&N CIA is in as well. No sense taking the stock intake off only to replace it a week or so later. If you go with the MSD's make sure you use the part number above. Their website states that it is part number 82428 which is only for SOHC 4.6L.

justbob
08-15-2010, 08:46 AM
So did this ever get fixed?

olds97_lss
08-19-2010, 08:34 PM
My 06 MGM has a bucking feeling at around the 2500 rpm mark. You can hear the engine cough, choke and then it kicks in and goes fine.

Had the fuel pump and filter replaced around 50K, filter again at 65K and it currently is around 85K. Pump was kind of pricey, $600 or so installed. I had a CEL that was saying lean and it would really choke and sputter badly then. After the new pump, it was better, but is still there and gets annoying when I'm in stop and go traffic.

Is there a tool/meter you can use to check each COP? I'm guessing mines about due for plugs and figured if the tool/meter isn't too pricey, maybe buy it and check each coil to see.

The only non factory item I have is a K/N air filter. I've cleaned the MAFS a few times, but doesn't seem to do much.

The idle has been relatively rough since I bought the car with 17K on it 3 years ago. I have a 98 MGM that runs smoother than this thing ever has and it has 170K on it!

Joey3571
08-21-2010, 08:43 AM
Yeah. It fixed the issue and gave me plenty of spark. Replaced battery and put on CAI as well. Lot's more gusto. Have a question for you all. How do I decode the Production Sequence Number. My last 6 digits are 624013. Cannot for the life of me figure this out. Is it number 62 of 4013? Or is it 13 of 6240? Some one help me figure this out.

LSp8
12-03-2010, 07:30 PM
I just started having this problem today which is the day after I lost my job (Talk about perfect timing). Anyway I'm getting a horrible shutter at around 2,000 RPM and a slight shutter at takeoff but it quickly goes away as you start driving. Hopefully it's JUST the coil pack and nothing else. It's still under warranty but I can't afford the down time at this point especially for a fix that's under $100. Heading to Autozone right now. It just threw codes P0316 (Misfire detected at first 1,000 revs) and (I think) PO304 for Misfire @ Cylinder #4. First problem I had with this car in 2 1/2 years aside from the ride control air compressor and ride height sensor last month which was a $1,000 but under warranty.

LSp8
12-03-2010, 10:59 PM
Just got a new "Duralast" coil pack from Autozone. I know how generic but I'll get a set of Accel COP/Plugs when I start my next job cuz I did not intend on spending a random $300-$400 today. Disconnected the battery to clear the codes and installed the new coil pack and back to business as usual in just 5 minutes. Oh and the mileage is 82,000 and all stock with the exception of the CAI.

underthehood
02-27-2011, 05:11 PM
I'm also having the same problems you guys are talking about. Only happens when im slowly getting on the gas, but when given more gas the car down shifts and runs great like always. At first I thought I could need a tranny flush, but not sure. Hope we can figure this out. I ran some fuel cleaner threw but hasn't helped. My interior lights are also acting up, at night my interior lights would shut off for just a second then come back on. Don't know if it's related but probably not. I never drive my MM just sitts in my garage, that probably also doesn't help.

NorthShoreChiMM
06-24-2017, 09:04 AM
Forgive me for posting on a 6 year old thread but these are the exact symptoms I'm having. Tranny flush a few months ago but I don't think they changed the filter. Fuel filter was done a few months ago as well. Stock coil packs, no clue on when or if the plugs have been changed. You guys thinking coil packs or TPS. Thanks in advance, this bucking problem got me scared think my tranny was screwed. Oh, yea 124k miles if that helps.

RF Overlord
06-24-2017, 09:53 AM
You can hear the engine cough, choke and then it kicks in and goes fine.NorthShoreChiMM, if this is the bucking you're having, I had the same issue with Mary's MM a number of years ago. Tried a whole host of things and it turned out to be bad plugs. They were Autolite coppers and had under 30,000 miles. I replaced them with NGK 4177s on Marty's recommendation and the issue was gone.

will-dan1
11-01-2017, 09:59 AM
NorthShoreChiMM,
Any updates with success. My 2003 with about 75K has been doing the same all summer. I have replaced the plugs, cleaned the MAF but still bucking. No codes, but I have not replaced any of the coils.

jmsa540
11-01-2017, 01:45 PM
happens to me and also happened to my 2000 Grand Marquis.