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Purchased new 09 Fit, Base model, manual trans w/177K- At freeway speed goes suddenly into "limp home" mode (drops to <40 mph), check engine light flashing until pull over, stop engine, re-start, then is fine. If I can get to roadside quickly, the check engine light goes out, if not quickly pulled over, stays on until I clear and then stays off until the symptom happens again. Get P0302, 0303 and cat codes (cats are young), and when cleared don't come back until next (random) event, but always seems to occur at highway speeds, not on surface streets. Have been reading the forum posts on this. Young, well-torqued spark plugs not the issue, but "mid-range" Rock Auto coils, installed late last year, may be the culprit (have better grade units on the ready to install) OR the perp may be a budget (not OEM) fuel pump module, also done late last year, just as reg maintenance. Pump makes some noise but that is typical, supposedly. Either way I am leaning towards the coils as it seems to be an electrical issue as it is cleared by re-setting ignition. Am wondering if it is the pump, though, because of fuel supply issues at freeway speeds (avg 70 mph). Otherwise, the car has been super faithful. Maybe ECM needs to be reset?
Feedback appreciated.
Thanks, Huff
The codes you listed already tell you what the issue is .. misfire on cylinder 2 and cylinder 3. If you have "better grade" coils on hand.. I would just swap them out to test to see if the issue persists.
Not sure why you would want to replace the fuel pump module with a budget grade one.. OEM is usually the best quality. Fuel pumps are also not a regular maintenance item. You replace them when they are bad which is rare unless you are running on empty fuel tanks 90% of the time.
The codes you listed already tell you what the issue is .. misfire on cylinder 2 and cylinder 3. If you have "better grade" coils on hand.. I would just swap them out to test to see if the issue persists.
Not sure why you would want to replace the fuel pump module with a budget grade one.. OEM is usually the best quality. Fuel pumps are also not a regular maintenance item. You replace them when they are bad which is rare unless you are running on empty fuel tanks 90% of the time.
Update. Changed out coils to Hitachi IGC0073 (bought on Amazon) and the problem persists ("limp home" mode if I touch 75/80 on the freeway)- thot these were the "good" coils (approx $65 each). Do I need to return them and go with an actual "Honda" coil? I did order an OEM "Honda" fuel pump module ($400!) to replace my ebay ($100) version, which I think is playing in, here, but will know after install, sometime in next week or two.
On another note- by coincidence, car was suddenly idling lumpy and slight "lurching" at slower speeds. Thot to myself, great, another problem to diagnose which may very well be created by all the parts (coils, plugs, injectors) I have been throwing at the old girl. Cleaned EGR and she seems to be back up to snuff.
Thanks for insights,
Huff
Correction- latest round of coils were $35 each.
I think I need to spend more money and find the OEM's- anybody know- can they be had from Amazon?
Thanks,
Huff
Did valves some months ago- they sound right and should be good.
Sparkers replaced and properly torqued, not long ago.
Didn't check the compression but might during the next go-round of (GA$P, approx $500 for the parts) new factory/OEM coils. Update in interim- installed (also GA$P, approx $550 for the part) OEM fuel pump module and the "event" (flashing CEL, P302, 304) did not happen in my reg 100 mi drive after, when/where it would occur. I think it was fuel supply by cheapo pump, as I suspected. Gas gauge works now like it should and mileage of back to good.
Installed the OEM (GA$P, expensive) ign coils, this morn and while at it I thot I would check the torque on the plugs- OMG, they all moved in a SOLID 1/4 turn, or maybe more. Am SO glad I checked, after reading the horror stories of plug ejecta.
Great forum.
Latest- had yet another "event", somewhat less drastic- flashing CEL, shut off by roadside, restarted, went away, and was good for some miles and then solid CEL, restarted and that stayed away. Almost saw it coming as the MPG reader indicated awful mileage on the freeway. Happened to have my OBDII w/me and checked w/o leaving car and P302 (#2 cyl misfire). Limped the rest of the trip at 60 mph and got to my destination, albeit w/bad mileage. Was able to limp the 50 miles home on surface streets with decent surface-street-mileage and am going to replace the rebuilt/remanufacture injectors w/OEM (GA$P, expensive!) and if the problem persists will see if the brain/ECM is rotting. Do they ever go bad? I am tempted to do the walnut blasting to see if that is contributing to the problems.
Ugh. This is getting unsafe, expensive and time consuming but I am not done yet.(said Custer).
Check sensors (on proper diag. computer)
Check fuel trims.
Compression test if you have the kit.
Make friends with a good tech,
Could've easily saved you hundreds had you just had a proper tech diagnose. Mid grade parts from rock auto generally work well, you may have a bad plug, but avoid amazon and ebay as much as possible generally. Good luck, hope it gets taken care of.
As it turns out, after removing the upper & lower intake manifolds, and accessing the intake ports- they are clean! I don't have GDI, but port injection! Will not do the walnut shell blast and just scrub with with sundry cleaning solutions and brushes, reassemble and be done with it. I am returning many of the unused tools/materials until it comes time to do the wife's HR-V (which I think is GDI). If am am still between jobs I may pursue offering the service to others.
Did quite a bit of disassembly (throttle body, fuel rail, air boxes, battery- having the upper intake manifold out of the way made for quick work of replacing the injectors) What I did find, aside from minimal junk inside the ports, was # 2 spark plug (Denso Irridium, bought on Amazon) has a faulty electrode! Don't think it was fried off, as no indication of excessive or big heat/spark, so I probably installed a flawed plug, as was. Can't say for sure, but am hoping it solves my CEL-at-freeway-speed issue. It coincides with the # 2 cylinder misfire code. Going with NGK Irridium izfr6k (pricey). I still believe the OEM fuel pump module is helping, as the codes are becoming minimized/specific, after changing out the knockoff module, also replacing the non-OEM coils with factory parts may have aided in cutting down on the code. Again, not sure but as I plan on keeping the car, forever, basically, it offers some peace of mind, if nothing else (have gone cheap-to-midrange on many parts in the past and I am in "the 3rd act", if you will, ergo, I am wary of going too cheap, these days. Pre-cleaning- Looks like most of the "after" cleaning photos!
Hope to have all back together in a few days and will follow-up with test results.
Thanks, again. # 2 plug- note no tip on electrode (see other plug pic, attached here, for comparison as to what it should look like Proper electrode
Looks like you'd be right on the money there. Can't see it too well but by the bad plug posted, if the blackness is ashy, means unburnt fuel normally, hence the code. I think you'll like NGKs, they're awesome. Good luck!
Just for yucks, as I had symptoms of a bad MAF, I changed it, too. Seems to have taken the lump out of the idle. Have yet to do my extended freeway test, but trips around town and short stints on the freeway indicate that I may be back to normal. Would be good as I am tiring of surface streets for any length of trip.
Did a 30 mile freeway run which usually incurs, of late, a CEL and none occurred yet the mileage was mediocre (33 mpg avg) and varied dramatically from very low end of the scale to pegging the other end. I am really hoping the the ECU is "learning" and my mileage increase (all sorts of new parts- (all OEM) injectors, coils, fuel pump module (all big buck$), good plugs, MAF, and cleaned air intake & throttle body. Drained the electrical system (joining the + & - battery cables for 10 to 15 seconds) when installing MAF. Re-cleaned EGR, and cleaned intake manifold runners (were oily near the head but dry near the upper intake manifold). Bought a dongle to run a laptop during driving for real-time testing and will try that. Car starts right up, idles near perfect, pulls like a train and behaves well, otherwise. Getting approx 30 mpg around town, whereas used to be 34 and 38-40 fwy.
Hmph.
Update- bought a laptop plug-in analyzer (no affiliation) and it is a simple readout (I expected more detail and access to ECU info, but may not have delved deeply enough, yet) and took for a combo freeway/surface street run and the mileage indicated in the "dashboard" mode (was hoping this could map fuel more/better- but it does indicate gph, total gallons fuel usage) was in line with what the dash mpg meter indicates, which is good, I guess, but I still have really low (20 to 25 mpg) when on any sort of incline or level section of road, trying to get up to 65 to 70 mph on the freeway; if I back off the throttle it shoots up to the 50's thru 100's mpg. Around town is averaging 30 to 31, without "spirited" driving (altho around town it doesn't seem to make much difference for total mpg, if I am a bit "lead-footed"). All around mpg, indicated, is hovering around 31. Used to be, before all my maintenance-minded 175K miles swapout [I was just trying to do something nice for the car for the long game] of coils, plugs, injectors, fuel pump module, (cleaned the MAF, now new MAF) and are all now back to OEM part$, I would net 33 at the pump, combo hwy/surface st, and I seem to be now netting about 31, at the pump, combo-driving, which is live-able but I can't help but feel that the uphill freeway minor sluggishness (and now gas-guzzling- mpg meter goes down to 10-15 mpg) and the wild swing if I back off the gas (and lose lots of freeway speed with an even minor lift off the pedal) has something to do with the throttle body/metering. With this new OBD@ reader I don't think I can "fuel map" (was hoping to). Have cleaned EGR valve (twice, recently), cleaned inside lower intake manifold (bottle brush to greasy runners near upper intake manifold). Not sure which way to go, here, for the next step of figuring/testing. To reinforce- both cats are young (<1 year), valves adjusted, no real parasitic drag on chassis, no CEL's (yet). Car pulls well around town and gets up to freeway speed okay, but a a dramatic loss of mpg >60 mph , on the highway. I did clean the throttle body w/MAF cleaner and have done the cycle reset (cooling fans come on twice to synch the TB butterfly mechanism). Do TB's wear out (car has 180K, now) and/or are sensitive to treatment/cleaning? I have a sneaking suspicion that me new (OEM) MAF is maybe a bit flawed. I hate to spend big buck$ on a Honda dealer diagnosis but I may drop the coin to someone that has a better diagnostic reader. Addtl note I do run a K&N air filter, and have for some years, lightly oiling, so as no not foul the MAF. I may pull my new MAF, clean, and install my spare paper filter element, just for yucks.
I live if the SFV of SoCal, LA if anyone has recommendation for an honest dealer.
Thx much.
OBDLink SX USB: Professional Grade OBD-II Automotive Scan Tool for Windows
...update...just cleaned (new) MAF and installed old/spare paper air filter element. Test drove freeway 10 miles and mpg seems to be better, OBD2 reader indicates higher that in-dash mpg meter. Finished test run with surface streets, all-around mpg, in reader, shows 35-ish, total, which is not bad, and better than today's earlier test w/K&N filter. Will be doing my reg Sunday 50 mi RT with laptop running reader, and current paper filter setup. At one point, in today's test drive, upon decel, 241 mpg indicated then back to 9 getting onto freeway ramp.
....furthermore...takeaways from laptop reader OBD2 dongle connected and running during driving: 50 mi fwy trip- total mpg 41, trip mpg 45 and coming back 40 total mpg, trip mpg 41 (return trip is more uphill); the dongle/laptop is much more sensitive in "real time" than the in-dash mpg reader, showing more dramatic swings in mpg and also reading trip mpg as higher than indicated in the dash, by approx 20%, ergo, my mileage is better than what the dash is telling me, yet will know better when I fill up, tomorrow and divide total mpg by gallons (last time was 31 and change). One of my fundamental problems is smoking- I quit for a couple of years and recently started back again, albeit to a lesser extent but I use the car as a "smoking lounge" and drive for a few miles, a few times a day, to have my nic fix, such that the short trips really ding my mileage (and my lungs).
Bottom line, if you are going for mileage, don't smoke and use a reader device for real time dats to enable biofeedback of throttle-to-load/road speed/incline conditions and you may very well get more miles per tank.
