runs good with acceleration/bad when not accelerating
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runs good with acceleration/bad when not accelerating
I have an F-150 EFI 351 that is really running poorly when I am just giving it a little gas. When I accelerate, it has plenty of power and runs well. I have already done A LOT of work to it and still have the same problem.
I have replaced the following: fuel pump, fuel filters (dual tanks), EGR sensor & valve, coil, distributor, plugs & wires, cap, rotor, control modulator, heat sensor, throttle body gasket and throttle cable.
I have had it plugged in. That is when they told me that the EGR sensor was bad and they replaced it.
Any ideas would be great! As you can see, I am willing to try everything!
Thanks in advance for your help!
I have replaced the following: fuel pump, fuel filters (dual tanks), EGR sensor & valve, coil, distributor, plugs & wires, cap, rotor, control modulator, heat sensor, throttle body gasket and throttle cable.
I have had it plugged in. That is when they told me that the EGR sensor was bad and they replaced it.
Any ideas would be great! As you can see, I am willing to try everything!
Thanks in advance for your help!
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From: Linwood, N.J. USA!
runs good with acceleration/bad when not accelerating
Ppacha, I may have had a similar problem with my truck. I had rough idle and a lot of black stacking, (black smoke like it was running rich at idle). It was a stumpper and the dealer did a lot of process of elimination with fuel pumps and other stuff. It wound up being the fuel pressure regulator. I have a 92' F-250 with a 351 V-8 w/ fuel injection. The truck ran good as always when going down the road but when in was at idle, it almost seemed like it had a carb on it and that it was loading up. Just a thought. Good luck.
Jakegypsum // Ford fleet, soup to nuts.
Jakegypsum // Ford fleet, soup to nuts.
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runs good with acceleration/bad when not accelerating
Thank you for the feedback. I screwed up! I am posting this for my husband. He has a 302, not a 351.
Do you know what it means if the sparkplugs are yellowing?
Do you know what it means if the sparkplugs are yellowing?
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runs good with acceleration/bad when not accelerating
You didn't mention O2 sensor(s). TPS can do this (at least on a 3.8). Check codes, bet you have "lean" code. Check for vacuum leak. Been thru this before....
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runs good with acceleration/bad when not accelerating
Sounds like it could be an 0xygen Sensor. Under full throttle, the computer goes "open loop" and ignores most if not all of the sensors. But during part throttle, the 02 sensor regulates the air fuel ratio. Had this happen on the wifes Plymouth Sundance. It surged and stumbled at anything but full or agressive throttle.You might want to try and unplug it and see if it at least changes how it runs. Dont know if that will work or not. On my wifes car, it did not trigger a check engine light but stored the code in the computer.
89 F150 4x4 300/4 speed 33.12.50 w/Rancho lift 3.55 gears
82 Mustang GT 302 C4 + nitrous=FAST
91 Mustang GT basic bolt ons- GM Eater
89 F150 4x4 300/4 speed 33.12.50 w/Rancho lift 3.55 gears
82 Mustang GT 302 C4 + nitrous=FAST
91 Mustang GT basic bolt ons- GM Eater
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