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- Joined
- Jun 16, 2010
- Messages
- 12
- Points
- 3,101
- City
- Edmonton
- State - Country
- AB - CAN
- Vehicle Year
- 2003
- Vehicle
- Ford Ranger
- Drive
- 2WD
- Engine
- 4.0 V6
- Transmission
- Manual
Hi folks, Volkswagen guy (mainly TDIs these days) trying to help my daughter with a new-to-her 2003 Ranger Edge 4l that belonged to her grandparents where it got just oil changes / air filters for 15 years and mainly towed a small trailer during the summers.
The initial issue was once-a-month misfire codes (P0316 generic, P0302 cyl 2, P0303 cyl 3). This turned into the same codes, but every few days, and a rough idle that got rougher. We took a first crack at it, including running a can of Tektron, brake kleening for vacuum leaks, misting water for coil pack / ignition wire issues, and the “clear-flooding compression “test” which sounded completely smooth between cylinders.
We then succumbed to taking it to a shop, where they started with new plugs and wires (LONG overdue, fair enough) and then a series of attempts (that they eventually refunded us for) including an O2 sensor (put the old one back), and a “professional injector cleaning”. Now the codes were P0201/202/203/204 and they recommended replacing at least all the injectors in bank 1. They claimed the engine "ran much better with injector #2 and/or #3 disconnected".
We declined having them do any further work and have just replaced all 6 injectors ourselves (Lordco reman). Unfortunately the truck now has a definite miss (particularly when cold), is down on power, and has a generic misfire code (P0316 generic misfire) along with P0206 (injector #6 issue), P0306 (misfire cyl 6) and (weirdly, to me) P0172 rich bank 1.
My hunch at the moment is that at the very least we got a bad new injector for # 6, but two things confuse me:
1) The rich code is for Bank 1, injector 6 is part of Bank 2 ??
2) As I understand the wiring diagram, injectors 1/2/3 are wired in parallel, as are injectors 4/5/6… so how would the ECU even know injector 6 specifically has an issue??
That said, we’ve run the truck for a couple days in case it had something to do with relearning the fuel trims, and just this morning my daughter reported there’s a P0174 (rich bank 2) in the mix as well.
It’s a big-ish job to pull the intake repeatedly... I’d rather have a reasoned plan in place before tearing into it again… but my first thought is at least believe the misfire on cyl 6, swap injector 6 with something over on bank 1, and see if the issues follow the injector. I’ll also do a careful check of the injector wiring (maybe a brittle wire crumbled?) and the resistance of *all* our new injectors, while it’s all apart again.
Don’t have access to a Ford service manual, my scanner is VW-centric with only basic OBD2 features, and of course these engines are getting a bit long in the tooth so I’ve not found anyone describing this combination of issues yet.
Any suggestions from y’all more than welcome!!
The initial issue was once-a-month misfire codes (P0316 generic, P0302 cyl 2, P0303 cyl 3). This turned into the same codes, but every few days, and a rough idle that got rougher. We took a first crack at it, including running a can of Tektron, brake kleening for vacuum leaks, misting water for coil pack / ignition wire issues, and the “clear-flooding compression “test” which sounded completely smooth between cylinders.
We then succumbed to taking it to a shop, where they started with new plugs and wires (LONG overdue, fair enough) and then a series of attempts (that they eventually refunded us for) including an O2 sensor (put the old one back), and a “professional injector cleaning”. Now the codes were P0201/202/203/204 and they recommended replacing at least all the injectors in bank 1. They claimed the engine "ran much better with injector #2 and/or #3 disconnected".
We declined having them do any further work and have just replaced all 6 injectors ourselves (Lordco reman). Unfortunately the truck now has a definite miss (particularly when cold), is down on power, and has a generic misfire code (P0316 generic misfire) along with P0206 (injector #6 issue), P0306 (misfire cyl 6) and (weirdly, to me) P0172 rich bank 1.
My hunch at the moment is that at the very least we got a bad new injector for # 6, but two things confuse me:
1) The rich code is for Bank 1, injector 6 is part of Bank 2 ??
2) As I understand the wiring diagram, injectors 1/2/3 are wired in parallel, as are injectors 4/5/6… so how would the ECU even know injector 6 specifically has an issue??
That said, we’ve run the truck for a couple days in case it had something to do with relearning the fuel trims, and just this morning my daughter reported there’s a P0174 (rich bank 2) in the mix as well.
It’s a big-ish job to pull the intake repeatedly... I’d rather have a reasoned plan in place before tearing into it again… but my first thought is at least believe the misfire on cyl 6, swap injector 6 with something over on bank 1, and see if the issues follow the injector. I’ll also do a careful check of the injector wiring (maybe a brittle wire crumbled?) and the resistance of *all* our new injectors, while it’s all apart again.
Don’t have access to a Ford service manual, my scanner is VW-centric with only basic OBD2 features, and of course these engines are getting a bit long in the tooth so I’ve not found anyone describing this combination of issues yet.
Any suggestions from y’all more than welcome!!
