2000 Mustang GT hesitation/stutter/chugging under load

02_Lightning

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I have a 2000 Mustang GT, 5spd with 48k miles and it started to develop a stutter/shutter/chugging while driving today. Any idea what it could be? No check engine light yet and I am curious if it may just be a bad coil pack. Any recommendations on what to check? It is a completely stock car that has never been abused... my mom drove it for the last ten years and I bought it this past fall. Thanks!!!
 

02_Lightning

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Yes - maintenance was kept up on the car. It has the original plugs/coil packs. Her commute was 4 miles round trip and the car sat in the winter time. Someone suggested it was a bad or gummed up EGR valve.
 

2001Bullitt

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I would change the plugs and check the coil packs. Use Ford plugs and packs if you need to change them. I had a stumble and it was a coil pack, I ordered accel packs and they made it worse. Put a new Ford one in and it was like a brand new car.
 

02_Lightning

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Think I will get a check engine light, or some sort of code stored for the problem it has? I have heard great reviews about the Accel packs, so I was thinking of getting them. I just didn't want to spend the money if that wasn't the issue. Also, if I have no code, I wonder how I determine which pack is bad.
Could this be any other issue?
 

02_Lightning

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Sounds like it could be:
1.) Bad coil pack(s)
2.) Maybe EGR
3.) Plugged fuel filter

Could it be a crank sensor? I was thinking about driving the car around the block this evening to see if I can trigger a check engine light. The local parts store that can read the code is about 5 miles away, so I should be able to get there and back... I hope. I bet that all of the above would be good to look at anyway to just replace and be done with.

Thanks to everyone for the input on this. I just wanted to get opinions before I spend money. I may not be keeping this car for long because of the lack of parking spots we have. I would love to fix it, and then sell for someone else to enjoy.
 

WHITE2000GT

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its definitely a coil pack...there is really no easy way to find out which coil is bad...the easiest way is to wait for the cel to come on. You can pull each coil individually and check the resistance, but that would take a while. But once the light comes on, take it to get the codes pulled and you should have a misfire on at least one cylinder...replace the coil pack for that cylinder and it should run fine after that...

its a 7mm socket that fits the retaining bolt btw...takes 5 minutes, at most, to change one.
 
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2001Bullitt

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Most of the time the coil packs wont throw a code. Mine never did either. I went to a buddys shop and we actually figured out which one was faulty.
 

02_Lightning

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It ended up throwing a CEL on the quick ride around the block after work. Cylinder #2 was the problem child and was fairly easy to get to. $48 later, and the car is all better... WHEW!!! I am a happy camper now.

All posters above - THANKS for all of your help!!!! I appreciate coming here with questions and getting help from people I don't know. Thanks again all!!
 

00stang37

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Not to hijack, I've been having the same issue pop up from time to time but it also wants to stall out when coming to a stop sometimes. I've had it looked at by a mechanic and also brought it to ford. There are no codes being thrown. I'm not sure if it's the same problem with the coil packs or not but do you guys know the best way to test them?
 

02_Lightning

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When this problem started, it was not too noticeable. However, the more I drove it, the worse it got... and it really started drinking the gas. As I pulled into the parts store to get the code read, it would barely idle. I am betting that you will need to swap the coil packs out... doesn't hurt to do them anyway. I priced a set yesterday that was $250ish for all eight shipped to my door.
 

00stang37

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Not to bring up and old tread, the stumbling idle and misfire like chugging under load is worse with the defrost or ac on. Not sure if this is still the same problem a's the OP or not. Any ideas?
 

96Mystic1717

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I just picked up a '99 GT two weeks ago and I've been having the exact same problem. Car is completely stock, 93k miles, one owner car.

Problem is only noticeable at lower RPMs.

Driven it daily for about 2 weeks and it hasn't tripped a Check Engine Light yet. How can I figure out what coil it might be without having to go through them all one by one?
 

mustangmike02

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My car is Doing this now, has 92k miles. JLT RAI, accufab 75mm throttle
And plenum (since install idle fluctuates) catback and x pipe with cats. A about 1500-2000 miles ago i put some injector or fuel cleaner with a full tank. But recently it has been run to low fuel light last two fill ups. When I popped te
Hood last night the intake rubber coupling was loose and air I
Believe was getting around it or leaking. Fixed that. Also I normally run 91-93 but
Last time my car was low on fuel I did put in 87. Not sure if it's weak
Gas, dirty fuel filter, or anything to do with my intake loose, or
If its a COP or spark plugs.
 

mustangmike02

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CEL came on, was cylinder #2 misfire. New COP installed runs good. As for the guy above, I would replace all your cops, spark plugs air filter check your maf, vaccume lines, fuel filter and hopefully it will run better?
 

Rv02gt

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Hey guys I own a manual 02 gt and I am having similar issues. Only I just replaced the intake manifold. All was good on day one, today I it out on the road and experienced this. I did get a blinking check engine light. I am a little puzzled. Idle is good regular drive around the block good, but when I step on it, this happens. Any suggestions. (Had a COP issue a couple years back but replaced it)
 

Stormtrooper00

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You can unplug injectors to see if any have now effect on idle and I know if it bogs under load it may be broken timing guides I had this problem with 120k bolt ons hate too hear timing problems hope this helps at all

Sent from my R1 HD using the svtperformance.com mobile app
 

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