p0171 slight miss at idle alot worse at 45 mph

cpyron13 · #1 06-08-2011, 05:42 PM

hey hey everybody! i have been having some trouble for a while now with my truck missing and it has gradually gotten worse. p0171 has remained on constantly with p0174 coming on every once in a while. So far i have replaced all known vacuum lines, plugs and wires, cleaned maf, changed egr, dpfe, and egr solenoid, and fuel filter. Fuel pressure also checks out good. Only other option that I no of is the intake gaskets. Is there an easy way to check them for leaks and where exactly are they? Im new to this so any help is appricaited!

cpyron13 · #2 06-20-2011, 07:50 PM

Problem has been getting steadily worse up to 55mph now. Any ideas at all?

Fordzilla80 · #3 06-20-2011, 08:45 PM

Hmm, both of those codes are for Fuel Injection System Too Lean, one being Bank 1, the other being Bank 2. You've checked your fuel pressure, and that's up to par. I'm thinking your injectors may be clogged.

I need more info. How many miles are on the truck? Done any kind of off-roading recently?

cpyron13 · #4 06-24-2011, 10:57 AM

Hey thanks for the reply. Truck has around 142k on it. Havent done any offroading. I was also thinking fuel injectors. Is there any way to check them other than replace? I was hoping there may be a cheaper fix before buying injectors.

Psychopete · #5 06-24-2011, 12:00 PM

would recommend figuring out which one is misfiring, then honing down on that cylinder to determine the cause. could be a lot of things; plug, wire, valve/low compression, etc. if you're really in a pinch for money, could try to clean a bad injector at home if it checks out and works with 12 volts applied (you'd figure it out in the cleaning process). compression test is the first thing I would look at if the plug looked normal. check resistence of the plug wire. noid light the injector to make sure it's getting signal, check the ohms on the injector. listen to it with a stethoscope.

cpyron13 · #6 06-27-2011, 07:45 AM

hey thinks for the replies. I'll try this out. What should the injectors ohm out to thanks again.

wangbungal · #7 06-28-2011, 07:48 AM

go get a multimeter and check for continuity on your fuel injectors, as some of them are probably gone or dirty, spray an electronics cleaner on it

ColinS · #8 06-28-2011, 09:18 AM

what about o2 sensors have you replaced those?

wangbungal · #9 06-28-2011, 10:07 PM

why would you replace an O2 sensor? Unless youre getting codes that youre O2 sensor is bad, I dont really suggest replacing it

cpyron13 · #10 08-04-2011, 05:40 AM

I recently replaced the 3 injectors on the side that was triggering the code. The truck ran good for the first 20 mi or so then the problem returned. It is not as bad as it originally was but about the same as when I first noticed it. Any other ideas?

cpyron13 · #11 08-18-2011, 02:17 PM

anyone?
anyone?
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