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Discussion Starter #1
Warning long winded post ahead.... I just copied and pasted this from my other forum.

I've been trying to trouble shoot some weird issues with my girls 6i. First of all no CELs are on the car. The car is a 04 6i atx with that lame ass sport shift crap and has around 100k miles on it.

Here lately she has been telling me that her car acts up from time to time mainly while in the drive through at McDonalds mainly. She says the car feels like its pulses and wants to move forward. So she has to press the brake harder to keep it still. Also she says she has has issues with the brakes before where she has to press the brakes harder to stop. Edit: She recently informed me that the Tach DOES go up by 300-500 rpms when it pulses forward.

The thing is I can't get the stupid car to act up when I drive it. We have taken her car everywhere for a week or so and it never acted up for me.

Also another weird thing the car does or well did was felt like you take your foot completely off the gas on the highway and just slows down.(I did not take my foot off the gas)That was the only thing that I was able to get the car to do but I since then taken it out and flogged it around and changed the plugs. That issue hasn't came back yet or at least she hasn't told me.

I have flushed her brakes out 3 times to get all the crap out of the system. The first fluid change on the brakes the fluid was pretty damn foul even with my bad allergies which is why I flushed it so many times.

Now I know this car is a fly by wire step so I do not know if the two issues are related or not with the pulsing. The issues only come up every now and then and you can't reproduce it on demand. This may sound like a stupid question but can you clean a fly by wire TB like you do a normal thorttle body or do I need to take extra steps in that?


Anyone have any idea where I can look to see what the hell is going on?

Edit: I know it sounds like somethings on its way out but what I have no idea... brake booster, TPS, throttlebody?
 

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Well I cleaned the throttle body and it did make the car feel smoother to her! However it made the pulse-ing in the car movement softer but yet more frequent. So I guess I need to hit it again with the carb cleaner another day.

It finally did it to her while I was in the car. It almost felt like someone very lightly tapping the gas but nor really enough to notice. Sort of like a extremely light lugging of a gear in a standard car but hers in a automatic. Again not enough to really notice on the tach but enough to notice while in the car.
 

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completely stock?

some have had those issues with intakes on the car. try resetting the ecu (if you don't have CEL's) by disconnecting the neg terminal for a couple minutes. in most cases that will clear up the issue, though the car will drive a bit odd as it relearns fuel maps. not sure the cause, but it's usually a tune thing
 

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completely stock?

some have had those issues with intakes on the car. try resetting the ecu (if you don't have CEL's) by disconnecting the neg terminal for a couple minutes. in most cases that will clear up the issue, though the car will drive a bit odd as it relearns fuel maps. not sure the cause, but it's usually a tune thing
Yep, 100% stock unless you want to count blue lug nuts. lol I will have to try that Wednesday/Thursday and see what the results are. Its kind of hard to do anything to her car beings I work nights and she works during the day.
 

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Discussion Starter #9
Change the ignition coil. In my case resolve the problem for my surprise the OEM was Motorcraft!!!
Ill have to keep that in mind. I know for a fact that they haven't been changed since we got the car wtih 36 or 46k on it and now has 126k-ish miles on it. Currently its in the shop for transmission repair (see my other thread). Depending on how bad the damage will be on the repair for that we will look into replacing the coils. I know the plugs have been changed but dont think the wires or coils have ever.
 

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I replace mine at 65 k and feel the car back to me, 126 k is a lot of wear for the coil.
Remember a lot of heat under the hood.
 

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Discussion Starter #11 (Edited)
I replace mine at 65 k and feel the car back to me, 126 k is a lot of wear for the coil.
Remember a lot of heat under the hood.
True but the underhood temps don't even compare to my MSP and the coils lasted longer then this. I know different car. However we recevently had the trans rebuilt due to the torque converter going out and sending metal through the entire trans. So maybe this sign in this thread was a early sign of the trans going.. no telling but ill keep a eye on her car adn see what happens
 
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