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little stumble at steady rpm!!

417 Views 5 Replies 5 Participants Last post by  ZeTeC808
when i'm cruising at a steady rpm, i could feel a little stumble/jerking.my idle is fine and when i accelerate, it sputters a little and then picks up.my check engine light came on.i took it to ford but i didnt want to pay $130 for a diagnostic test.the service manager said its probably my o2 sensor because of my race header.i had my race header (with o2 cheater) on for over a year and only now my CEL comes on.anyone have an idea of what is causing the stumble/sputter/jerking????


heres a list of my mods:
fc race header w/ o2 cheater
aem cold air intake
fc throttle body
custom exhaust
afx udp
diablosport chip
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Bad o2 me thinks. That is what happened to me when I got my shorty header/orp setup.

But I replaced the header with the stock one, took off the orp and put on the stock cat, and took it to the stealership. They said it was a bad o2. The second one I think. They replaced it under warranty but stated that it was due to my shorty header that the o2 went bye-bye. So they said if it happens again, it will not be covered under warranty.
when i'm cruising at a steady rpm, i could feel a little stumble/jerking.my idle is fine and when i accelerate, it sputters a little and then picks up.my check engine light came on.i took it to ford but i didnt want to pay $130 for a diagnostic test.the service manager said its probably my o2 sensor because of my race header.i had my race header (with o2 cheater) on for over a year and only now my CEL comes on.anyone have an idea of what is causing the stumble/sputter/jerking????
bad DPFE sensor... I get that all the time with my race header. weird thing is that they say it craps out because there's not enough backpressure! HAHA


They replaced it under warranty but stated that it was due to my shorty header that the o2 went bye-bye. So they said if it happens again, it will not be covered under warranty.
if you have the problem again and they deny service, make sure you have them put it in writing as to what caused the malfunction and why. definitely make sure they put it IN WRITING with the service manager's name/signature. if they refuse to, then then cannot refuse service. if they still fight it, call Ford Customer Service. refer to the Magnusson Moss Act (www.sema.org too).
Thats what my car did.
DPFE!!!
I am not saying it isnt your o2 because it just might be but I have had the 4-2-1 race header on mine since 45k and I have an o2 cheater and now I have 96k and I have had no issues with the o2's. My car was doing the same thing but it also would let the rpm's hang. As soon as I replaced my dpfe the stutter at a steady throttle whent away.

the dpfe is also the cheaper of the two to replace.
thanks for the replies!i may sound like an idiot, but where is the dpfe sensor located
and is it easy to replace?
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