I just bought the car a few weeks ago. and of course they didnt mention it had a problem. It does have a check engine light for fuel system to lean. p0171 i believe. i will confirm it and edit if thats the wrong code number from memory. So the car runs fine when its cold. like im in south florida about to go to work right now and the car is going to start right up. fuel consumption is high. only getting like 20mpg. but the real problem is after i drive it for say 30 plus minutes that everything is nice and up to temp. when i park it and shut it off. if i leave it off for say 5 mins. when i go to restart it. it will crank start kinda and shut back off. like no fuel. then it wont start back up. just turns over. it will start after like 30 mins of cooling off. and starts even faster when i pop to hood to let the engine cool off faster. i change the coil packs no change. and i am going to do a valve adjustment but i dont think its this as i would think this would always not start if they are that bad. and i do hear the fuel pump running when we are in the no start time frame. so i dont think its that. i did spray starter fluid when it wasnt starting and still it wouldnt start. so it seems like a spark issue. im thinking maybe a dying crank or cam sensor? but no codes for that. and on my little odb2 scanner. it lets me see rpms live data. and while cranking its showing 3xx rpms. so im guessing the crank sensor is fine. so maybe the cam sensor is what controls spark? let me know what you guys think. thank you

 

Any aftermarket alarms?
From experience the problem itself looks like a faulty coolant temperature sensor (engine head thermostat housing)
So if your OBD -2 scanner reads the life data, check the ECT1 reading and while cranking look for ignition timing angle (cam sensor).
also check for the B+ power at coils and injectors at the time it isn't starting
Low fuel economy with lean code points to marginal A/F ratio sensor

 

Thank you Dr J for your response.
So when the car won't start. I have looked at the ODB2 readouts. And while cranking it does show 300 plus RPMs. It does show cylinder one timing advance does move up and down. I can't recall if it was reading correct coolant temperature. I'll have to double check I think right now the car has been off too long where it will actually start again. After I posted this this morning on my way to work I did notice that while giving more than will save 50% throttle my O2 sensor was definitely reading lean versus below 50% throttle where the command and the actual were pretty much good to go. When I do go above 50% throttle I can definitely feel the motor isn't as fast as if I let go of the throttle a little bit it will actually accelerate faster. Which those things are probably not anything to do with the no start. So I'll figure out those later which will probably increase my fuel economy. But it seems like you're saying a faulty coolant temperature sensor would prevent the engine from starting? As in no spark. And by the way the ODB2 scanner I'm using is the MX plus. I can still return an exchange for something else if you guys think there is something better than that.

 

I'm using Innova 3040 series just because it reads ABS codes.
If ECT sensor reads 40 degrees C with engine at normal temperature (85 to 90) during no start condition it's definitely at fault. Bad air intake temperature sensor can cause poor fuel economy and sluggish performance under adverse weather condition , but will not cause engine to die .
You can check for the spark by removing coil from the well, plugging connector back and holding the end about 1/4 " from the good ground (better to use a spark tester with a clip and calibrated gap)

 

Alright so this morning I drove 35 mins. Parked. Came back to the car after 15ish mins of it being off. And we are now in the car with a no start situation. I actually made a video and I'm trying to see if I can link it here. So for the first couple starts it stutters that gets trying to start maybe half the cylinders or so. But after two maybe three attempts of that it'll just turn over as if nothing's happening besides the starters turning over. I think maybe in my immobilizer was going crazy but the green light on the dash when you first turn the key on is green and then goes away. I believe if it wasn't detecting the key it would be flashing. How about like a main relay. Or do these cars not have a main relay cuz I see there is a good amount of relays that I have no idea what they do as the owner's manual doesn't show anything. I know the blue one is the fuel pump and I believe the brown one is the main fuel injection. I feel them click when I turn the key forward so I'm not sure if maybe those are at fault. And looking at the ODB scanner for the coolant temperature when we are in this no start situation my coolant temperature is at 174 degrees Fahrenheit. When I shut the car off I looked at it and it was at 183f. So I don't think the coolant temperature sensor is to blame. Any ideas? Here's the link to the video https://photos.app.goo.gl/C7edt6rcAFt7D18s7

 

What does the black relay above the brown relay do? better yet do we have diagram on what they all do? i cant believe the manual only shows fuses. and online all i have been able to find is 2010 and newer. thank again.

 

How about spark? Condition of the spark plugs? sound of the injectors?
You were mentioned that the fuel pump makes noise (working when the key is turned on) can you double check on that I'll pull some schematics tomorrow

 

• The GK5 has a P0171 (Fuel Trim System Lean Bank 1) error code associated with the injectors:
  • From the forum: https://www.fitfreak.net/forums/3rd-...ode-p0171.html
  • From random googling: https://www.700r4transmissionhq.com/p0171-honda-fit/
• It appears the GE8 also suffers from P0171
  • From the forum https://www.fitfreak.net/forums/2nd-...ode-p0171.html
• Another P0171 source DTC Troubleshooting: P0171 (45-2), P0172 (45-1) (5MT) points to MAP or O2 sensor.

My guess is MAP, Injectors, or O2 sensor. Probably best to go to a mechanic armed with these details to avoid blind shots in the dark on troubleshooting the actual issue.

 

Thanks for the help guys. I really appreciate it. So I forced the problem to happen. And i bypassed the relays just to make sure. And still no go. I actually do have spark when in a no start situation. So it's pointing to a fuel issue. I have a fuel pump that works I'm going to test it out. Going to be a few days though. Busy week. I'll report back when i have an update. Thanks again for all the help.

 

Question. Should i be able to see both o2 sensor voltage on my odb scanner? I cant see anything for bank 1 sensor 1. I can only see bank 1 sensor 2 which at idle fluctuates from .07 to like .9 volts.


Also quick update. It seems that if I use some starter fluid. Spray into the tb turn over. For a few seconds. Off for a few seconds. And turn over again the engine starts and runs fine again. Almost as if the starter fluid is cooling something down faster. Letting the engine start again. Ill I'll see if I can make a quick video of it tomorrow when I got to work.

 

Bank 1 sensor 1 is A/F ratio sensor so instead of changing voltage, it changes current direction (alternating between + and -); the OBD2 scanner will typically show constant 0.66 volts. Next time try to start engine holding accelerator to the floor and see if it makes difference.