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Help with hesitation between 2000-3000rpm

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ArizonaBOSS

Because racecar.
Moderator
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Arizona, USA
No; there is an inline filter just under the driver's footwell. You can see it once you jack the car up. It's got a plastic cover over it.

http://iihs.net/fsm/?dir=968&viewfile=Fuel%20Lines%20and%20Fuel%20Filter%20-%20Exploded%20View.pdf

Here is a guide that says "05-10" but the procedure is the same for our cars. http://www.americanmuscle.com/fuel-fitler-0510-install.html

Relieve the fuel pressure first by pulling the Fuel Pump relay out of the engine bay fuse box, then try to crank the car for 4-5 seconds (it should not fire; if it does just let it die).
 
ArizonaBOSS said:
No; there is an inline filter just under the driver's footwell. You can see it once you jack the car up. It's got a plastic cover over it.

http://iihs.net/fsm/?dir=968&viewfile=Fuel%20Lines%20and%20Fuel%20Filter%20-%20Exploded%20View.pdf

Here is a guide that says "05-10" but the procedure is the same for our cars. http://www.americanmuscle.com/fuel-fitler-0510-install.html

Relieve the fuel pressure first by pulling the Fuel Pump relay out of the engine bay fuse box, then try to crank the car for 4-5 seconds (it should not fire; if it does just let it die).

I believe that filter is only on the GT500. I don't remember seeing one on my car but I never really paid attention either.

If you look under the part number on the link you provided it says : 5.4L vehicles only
 
I pulled the plastic cover off under the driver side rail and didn't see anything looking like a filter. I'll recheck later.


Terry
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Me too. This issue is so strange. Others have it and most don't. To rule out my issue being exhaust noise from the side pipes I'm going to completely block them off.


Terry
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At 50k+ miles I could see this possibly being a fuel filter thing, though I remember when my car was brand new, around 2k miles it would do this. My new motor also does this and it has about 300 miles on it.
 
I noticed it just after the long tube install 5 months ago. Never felt it with stock manifold with cat deletes and kooks side pipes.


Terry
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69mustangman said:
I noticed it just after the long tube install 5 months ago. Never felt it with stock manifold with cat deletes and kooks side pipes.


Terry
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Tuning issue? Have you had it data logged doing maybe a slow pull through the hesitation area?
 
Yep, sent logs to both AED and Lund. Nothing shows up. Both said they need to see the car. Not possible from the east coast. Seems strange that it followed the oem manifold and tb through the cobra jet manifold and tb. After the CJ upgrade both sent a new base tune to datalog which in my mind meant we started fresh with the CJ upgrade.
I'll eventually take it to Ford or find an ex service tech that has his own computer.



Terry
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That's why I'm thinking the hesitation is diff/drive shaft related and not engine related. During my hesitation, I don't notice any RPM or engine noise fluctuation, but we could all be having different problems.
 

576

Sorry to state what seems obvious, but aftermarket tunes, headers, throttle bodies, no cats, yes cats, different manifolds, etc... Did the car exhibit any issues prior to changes? I use both the silver and red key at the track/ street with no mods. down to the stock air filter. I have used a simple K & N drop in filter in both my '12 Boss and a prior '12 track pack GT and noticed a drop in fuel mileage. NO... I am not concerned about mileage and my Boss is not a daily driver. However, it does tell me these engines/ management systems are quite sensitive. Get back to basics & the cause will most likely be quite obvious.
 
576 said:
Sorry to state what seems obvious, but aftermarket tunes, headers, throttle bodies, no cats, yes cats, different manifolds, etc... Did the car exhibit any issues prior to changes? I use both the silver and red key at the track/ street with no mods. down to the stock air filter. I have used a simple K & N drop in filter in both my '12 Boss and a prior '12 track pack GT and noticed a drop in fuel mileage. NO... I am not concerned about mileage and my Boss is not a daily driver. However, it does tell me these engines/ management systems are quite sensitive. Get back to basics & the cause will most likely be quite obvious.

My car's driveline is bone stock and it has always displayed this issue.
 
1
0
Exp. Type
Drag Strip
Exp. Level
10-20 Years
Ct
By chance I know this is a old thread but I have same exact issue been trying to figure it out for for 2 years and had replaced motor 3 times, new engine harness, and every sensor as well.
 

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