Hi everyone. First post here. I bought a '09 Fit Sport (AT) as a commuter car from an auction (supposedly run and drive). Anyway, car was dropped off today and it has no acceleration at all and car will not rev/increase RPM's. Hooked up my scanner and it has p0303 code for cylinder 3. I already have plugs/coil packs on the way for preventative maintenance but that doesn't seem that it would cause no increase in RPM's. Any thoughts or suggestions? I have a trusted mobile mechanic coming next week but might be helpful to narrow the focus.

Something similar happened with my Tucson this past summer and the cat converter was clogged . Hoping it's not that.

I did a carfax search for any maintenance and it seems very spotty.

 

Hate to be that guy, but there's not enough to go on here. I will say that if your catalytic converter was bad enough to prevent your engine from speeding up at all I'd think you'd see a code for it. A misfire should make it idle and run poorly and noisily, but I can't see why such a thing would prevent increase in rpm so much as the usefulness and safety of increasing it. The first and only thing that comes to mind for a car that starts and idles but is unable to increase RPM is a problem with the throttle/throttle body assembly.

Did you instead mean that the car accelerates poorly, idles roughly, and is slow/struggles to increase rpm?
I'm to understand that the vehicle's knock sensor can mess up timing to preserve the engine, and that can mean alteration of throttle response and stuff.

All that aside, welcome aboard, friend!
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Sorry for the poor description, I tried to drive it briefly home from where it was dropped off. Idles roughly, no acceleration and wouldn't go over a few miles per hour and not even up the slightest incline. Thought there would be a converter code as well if that were the issue.

If a fuel pump issue, would have thought more misfires that just cylinder 3. If a transmission issue would think rpm would be normal but no motion.

Will replace the plugs/coils tomorrow and see if anything changes.

 

Right on! I think verifying the components involved in spark would be a fine starting point. Bang out the air filter too! Plugs are a bit of a pain just as a heads up. I can post up the way to handle em tomorrow if you want. The hood hinge covers (plastic) come off, then wiper arms. Open the hood and disconnect the wiper fluid line where it connects to the plastic cowl, remove the plastic cowl (lots of clippies and tabs on it, do be careful!)
Wiper motor gets unbolted, disconnected and removed, then the metal cowl it sits on. Then you're good to go! 😂

Think all you should need is 14 (wiper arms) and 10mm (wiper motor and metal cowl) sockets to get through it all, extension for the metal cowl and wiper motor's bolts bolts, and of course some pry tools (I use plastic ones) to get the plastic cowl off.. Its a pain the first time around. Replacement clips are purchased via amazon cuz some break, just try not to break the tabs at the front of the cowl.

**revised spark plug torque: 20ftlbs.

 

Thanks. Got the plastic cowl off last night but not the tray underneath yet. Waiting for the coils to show up today. May need to run for a small torque wrench, mine is one of those big Harbor Freight ones which probably won't fit back there. I usually do plugs by feel but sounds like these are a stickler.

Did replace air filter last night. It was pretty dark.

 

Nice job! You make it sound like a snap
I'm looking forward to hearing what's going on with the car. Do note if plugs are loose or just snugged. From what I gather most folks don't have issues with plugs loosening, but a good number of people have, and it's caused misfires. I'd also recommend against anti-seize.

Hey, while you're in there you could bang out a valve adjustment if you want! Here's a link to a write-up for it. it has specs and such. I'd also whole-heartedly endorse the purchase of hondabond silicone should you undertake the job, though I'm sure any RTV would do for the application since it's just sealing seams on the head against the valve cover gasket.

those two things are all the engine needs based on my personal experience.

 

So much easier doing it blind from reaching behind the engine today. Found my #2 and #4 loose. Replaced with NGK and decide to remove all cowl in order to properly torque it to 20lb ft. What a pain in the ass.

 

Man, what a pain. Replaced the plugs/coils and upstream o2 sensor. All of the coils came apart trying to get them out of the wells. (three different pieces). From left to right, plugs 1, 3 and 4 could have been unscrewed by hand. I put the spark plug socket and extension into the well and attached the wrench but they came out with no effort. Put in new NGK plugs and Denso coils and car fired right up with no flashing CEL and revs easily. However, I'm too wimpy to try and drive it because I live on a mountain and worried about another tow if it won't get up driveway.

Bonus, now the power steering works again.

If I can get on ramps, oil and transmission fluid tomorrow.

 

Nice work!!

You can let it idle for 30 if you're worried. that should be enough to pop a code I think, or it was for me anyways.
I'm surprised to hear the coils came apart. I may be lucky in that department as mine never gave me trouble.
I'd recommend checking the trans fluid when you're able, and since it's new to you, getting rid of the old brake fluid and coolant (and trans juice) since the previous owner probably never did.

Also very surprised to hear power steering failure somehow correlated with the misfire. Not too versed in electronics, but I wouldn't have suspected. Numerous folks have mentioned power steering non-op lately and I had no idea what to point them towards. Will keep your experience in mind for the future.

Looking forward to hearing your experiences with the car. On my end troubles have been minimal - a check engine only meant plugs and/or valves. Anticipating that with your work done it should run well.

 

Well, things were going well. Car got a p0171 code which was fixed by valve adjustment and injectors. That code is gone but the p0303 is back (car went into limp mode) and so is the p0141.

Thinking of replacing the whole harness but not sure how long it would take/how hard of a job it is.

 

So cylinder 3 again and downstream o2 test failure..

If it helps any, I started doing wheel bearings on an 07 escape hybrid today. Well, I forgot to get spindle nuts, and neither ford or advance auto stock 'em or can order them, so I'm told. So, to the rear! Wheel hub nuts just as big.. Went ahead and took one off. No videos for the FWD, and the shop manual says to "remove hub." Well, I couldn't see any way to press out the bearing since the assembly is very large.. so leave it on! Penetrating fluid, extension, mallet. It's nearly free, but my left hand grew a glove size. And I'm finding that the hub seals available don't match appearance of those on the FWD.

Any trouble with the valve adjustment? Think there's any potential for wire damage in the o2's circuit?

I've built a wire harness before. I can't speak for the Fit, but I had to pull the engine to get the old one out! Provided a harness has all the necessary bends in it, it's pretty easy to line up and click in, I'd worry this might be jumping the gun though.

If all your work's gone well and you feel good about it, I'm a little worried that there may be an issue with cyl 3, like like a crack.
As for the o2 sensor, the downstream is fairly cheap I think. I found an article that addresses the code. It's a little too general for my tastes, but checking grounds and wiring, making sure the sensor is getting voltage all sounds like a good idea.

Didnt see your other thread! If you washed your engine bay it may take 3 or more days to dry out. Did'ja fire it up before then?

 

Valve adjustment went well, friend who is a mechanic did it while I helped (watched) including the injectors. Most of the valves were actually a little tight rather than loose. We didn't really mess with the harness but I'm guessing it's something in the harness in that general area.

Always something - check fuel cap came on tonight while driving so I bought a new one. Code stayed on, cleared it when I got home so we'll see if that fixed it. Other than that, car drove well for 50 miles with no codes or pending codes.

Strange.

Understand about the wheel bearings. Lucky that cars I've owned combine the hub/bearings so just a few bolts and use a puller on it.

 

So it's doing all better now? If so, I'd figure it just needed to dry out. Had some funny issues resulting from water. When I was a teen, the family learner was a 91 Toyota Previa. The splash guard was ripped off at one point while testing out the AWD feature There were two instances that followed where a deep puddle left me stranded. A day or two later it'd be back up and running.

Fun side note: If anyone thinks plugs on the fit are annoying (they are,) the first plug on that van had to be accessed by flipping the front passenger seat up, pulling up the carpeting in its legroom, and removing a 12 or 14 bolt hatch.
When the van finally started to give up at 250k, I took my first look and discovered that our family mechanic had never changed that front plug. That gave me my first push into automotive!
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As for the wheel bearing, I need a slide hammer puller set to get the hubs off in a reasonable fashion. Should be here tomorrow!

 

Well, the water was from a few weeks ago. Concerning that the same code came back after working on the car.

Yes, worked for a drugstore growing up and we had an '83 Econoline to drive around. Remember watching them remove the inside cowl to do anything to the engine. Fun times.

Good luck with the bearing.

 

It's got to be something with cyl 3 then. You replaced plugs without doing full disassembly, right? Think it's possible that you might have a crack in the cylinder head?

Well, I can get up the troubleshooting procedure some time soon and go over it. Maybe Honda's thought of something we haven't.
A compression test could be of use, too! I noticed you're somewhere nearby, you could borrow my kit if you'd like.

If all else fails, could fork over ~$100 for a dealership inspection.

 

We'll see. Drove to work and back today, runs like a top, no codes except now a gas cap code. Replaced gas cap and still code so will check to see if some hose leak near purge solenoid.

Car is getting good mpg for the age.

 

Just adding this - I had a similar issue a couple years ago - very little power, basically couldn't go more than 35-40 mph on flat and 10mph if lucky up a hill. Honda dealer originally diagnosed as fuel injectors and replaced all. Called just before I left to pick up to say 'whoops, that didn't fix it'. They screwed around some more and it ended up being the PCM which had to be replaced. Very lucky for me was still 3 months left on my power train coverage. They ended up not charging for the fuel injectors but I did pay like a $200 (mis)diagnosis charge.

 

The p0171 code came back again (after injectors/valve adjustment - which cost me a third of what the dealer wanted). I purchased a new MAF and installed and haven't had a code since.

 

@beezle Glad to hear the ECU replacement worked out, but I'd really love to know why it failed. Back in school I was thoroughly persuaded that a bad brain (ecu) is never a proper diagnosis, at least not until every sensor, wire, electronic device in associated circuits is tested. Did they offer any reasoning?

@tbearfit How'd you settle on the MAF?
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Power train control module is what they ended up replacing to fix the issue. Been fine (driving wise) since then.