My daughter has a 98 mitsubishi eclipse 2.0.129,000miles she has replaced the plugs and wires, It has error codes p0171 and p0301 lean fuel, i have checked for vacuum and gasket leaks with brake cleaner no indication of leak any where have checked fuel injectors for continuity all around 14 ohms. I have erased codes but eventually come back, at first start will run and rev perfect for 3-5 minutes then run a little rough, if i turn it off and restart will run perfect, this happens on all restarts and after 3-5 min it returns to run rough. has new air cleaner, new o2 senors, new plugs and wires and have run lucas injector cleaner instead of taking rail and injectors out and cleaned manifold sensor. any help would be appreciated thanks for reading email@example.com
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1998 Mitsubishi Eclipse Question: error codes p0171/p0301
Answer #1pushrod September 01, 2013, 09:47Master
Possible vacuum leak, injector probmem, low compression or ignition fire problem. ALL FOR # 1 CYLINDER!! (PO301)
Since it also has a lean code, start with vacuum leak AT # 1 or INJECTOR/FUEL restriction AT # 1.
Replycrash77, September 01, 2013, 09:53Rookie
thanks for reading would it be the coil pack for the ignition
Replypushrod, September 01, 2013, 10:00Master
VERY POSSIBLE!!! Does this engine have one or two coils? Could have either. If two packs, can swap to see if misfire follows coil. Either way though, coil can be the trouble!
Replycrash77, September 01, 2013, 10:12Rookie
i wish there was 2 only 1, coil looks, new have to ask my daughter, going to go work on it with her this afternoon and check egr, and replace fuel regulator since she has it. maybe i read more into it but how can you check for vacuum leak at #1 i sprayed cleaner all around injectors, gasket and vacuum lines with no change.
Replypushrod, September 01, 2013, 10:27Master
Consentrate spray at intake manifold AT # 1
Replycrash77, September 01, 2013, 10:32Rookie
on my way now, i did do as suggested before but will repeat T.Y. for your time
Replypushrod, September 01, 2013, 10:38Master
Replycrash77, September 01, 2013, 16:01Rookie
I sprayed the crap out of it no change, she had most of the vacuum lines replaced, but i do hear a hiss by the fire wall or front of motor but not sure if its the motor, not use to what it sounds like, im going to bring it home so i can remove manifold and injectors and give me more room to look back there. she has'nt replaced egr there is two lines one had air flow the other didnt, dont know if its normal. One thing i noticed today is slow acceleration is ok and also had to put gas in with a can and fuel came pouring out of the neck metal against metal former owner zip striped it (dumb ass)so there is no pressure in tank is that a possible cause THANKS AGAIN !!!
Replypushrod, September 01, 2013, 16:19Master
Don't think that will cause this, just keep after the misfire on # 1 cyl. first!! When it starts running rough, unplug # 1 injector to see if it gets worse or stays the same!
Replycrash77, September 01, 2013, 18:35Rookie
thanks pushrod will do the unplug, she and i are both learning, will try your idea then remove manifold, have a mechanic i trust but low on funds plus shes getting an education she tells me how the guys at the parts place are suprised that she can understand them (proud dad)
Replypushrod, September 01, 2013, 18:48Master
That's COOL, and you should be proud!! Tell her that i too am proud of her because most men folk don't know squat about cars anymore. Everyone should have to take a course in basic auto. repair before getting a drivers license! Understanding how a vehicle works makes for safer drivers, I think.
Replycrash77, September 01, 2013, 18:57Rookie
will do shes checking these posts also some people shouldnt have a kid or car, im lucky usually i figure it out most of the time, knowledge is power i think. i use to subcontract construction you would be amazed at what people cant or wont do or try, what are they gonna do when the comet hits l.o.l so if i unplug no#1 what am i looking for, i know its going to misfire