So last week and today, the CEL and TCS came on when I started the car while "hot", after driving it, turning off, sitting for ~30min, and turning it back on.
Both lights stayed on until turning off the car, when started again the TCS light turned off and the CEL remained. After sitting for a few hours the CEL was no longer coming on. It was my understanding it took some miles for the light to clear itself if the problem was gone, apparently not. It's done this twice now.
The car runs perfectly fine, engine is smooth and tranny shifts as usual. I can't get the codes read at a parts store since I'm in Cali, but I'm tempted to dish out some cash for a cheap reader.
Any ideas on what this could be?

 

No idea until codes are Read...
But Since you got the Codes until the car was Hot Might be some Ignition or Sensor Issues... but Im only guessing here.

 

Ya i know, need the codes lol. Was trying to see if there was a known cause to this type of pattern of the light coming on when started hot, and clearing itself after sitting.
Thanks for the input

 

Possible Evap.. gas cap not tight... common issue, just turn it two round the next time you get gas.

 

All we can do is guess without having the codes. IF I had to guess I would guess a P0401 code for the egr ports being plugged. But that is only a guess. Get a scanner and get the codes

 

harbor freight tools is your friend in Ca for an obdi II, reader for less than 100$,,and coupons for 20%,,

note gas cap minimum 3 clicks,,any more is just it bumping over the torque limiter,,any less can allow vapor prob

only thing I recall over summer was a fuel pump RELAY being bad on a few TLs on here
with a hot start problem,,not sure if that was warning lights or just hard hot start issue

a CEL after seafoam with poor after drive will self clear
a cel from loose gas cap will self clear after fix and several drives
most other codes should keep the light on

 

Guess I'll have to get a scanner and wait for it to happen again. Just thought it was odd that the light would go off after sitting for a while, like 01tl4tl said,most codes should keep the light on. I'll re-tighten the gas cap. Thanks everybody.

 

Check Amazon. The often have great deals on scanners

 

did this start right after putting gas in?
you are on 91 octane and name brand stuff?

visually inspect the gas cap seal for compression or tears..and 3 clicks is ON

the codes should be stored even if the light went off,,until you clear the ecu manually

compare amazon v harbor freight tools,,they are everywhere

 

If you or a friend has an android phone/device with bluetooth, you can get an "ELM 327 Bluetooth OBD2 scan tool" and use an app called 'torque.'


It's a pretty cheap way to get codes and other nifty info about your car.

For the money, it really beats out a cheap scanner.

 

Finally got the codes pulled.
P0304, P0305, and P0300
I know a common cause of our P0300, random misfire, is a bad coil pack. Would it be safe to assume the other codes area result of the P0300 and it could only be a single coil pack, or could it be those two cylinders?
Plugs are new and correct.
Could the coil pack be heating up and then not work properly when cranking/on start up and that's throwing the code?
Is there a way to narrow this down? The CEL is so random it'll be hard to swap out a single coil pack and test results, and I'd hate to spend the cash if it's not needed.

 

The codes and symptoms you've got are also consistent with the winter gas/fuel boiling problem that happens on 2000 and older models. Someone else on the forum has recently posted quite a bit about it recently; and my daughter's car is afflicted as well. Nobody's found a solution yet that I am aware of. The official acura tsb calls for an updated fuel pressure regulator and a new pcm.....a little pricey. The person who posted about it recently tried just the updated regulator, with no pcm, and it didn't fix it. I'm still tempted to try one on my daughter's, tho.

 

Many things can cause the misfires, as you probably already know chasing it.
I'd suggest trying to get the problem misfires for #4 & 5 to move. You may want to inspect the plug's condition,
even though they're relatively new. Check that the electrical connectors for the effected cylinder coils and also the
fuel injectors are secure.

Have the fuel pressure checked, next fill-up try running some ultra premium gas along with a fuel system cleaner. You could attempt to exchange the #4 & 5 coil packs with the other side. If the code comes up different, ya got it.

If you don't mind spending $50 for a new coil, then try swapping one at a time......until you notice a difference. You have to clear the codes each time. Also check all of your electrical grounds, as they can cause gremlins.

If all else fails, check the compression of the cylinders.

 

Ya misfires can be a pain. Had a miss on my '77 Datsun 810 (RIP) that I must have had every possible item checked or replaced, and it persisted lol.

The next step I had planned was to swap those to coils to other bank locations and go from there. I'll also double check the connections.
Only gas I have available here in Cali is 91
What fuel cleaner do you suggest? I've already seafoamed both methods.

 

Any top quality brand of fuel cleaner which is formulated to clean the entire fuel system from tank to injectors....and all points between ! Check your local parts store selection.

 

Haven't had a code come back until today....
p0305, misfire cylinder 5. Was a warm start again, plug looks fine. And it's not the coil I was worried about. Chasing this thing down is a PITA since it's so inconsistent.
I'm also now hearing a ticking from a black box under the hood, here's a pic I stole off the web, but I circled the box, what is it? lol

 

ticking noise from that evap valve is normal and you can swap places with the spark plug and see if code change to different cyl, narrowing down your issue.

 

Mine had a similar condition (CEL & TCS) and add in extremely rough idle and misfire code on 4 cylinders (2 on each bank) but not a p0300.

Replaced all 6 plugs & runs great now.

 

Ya that's the plan. Before I was getting two diff. cylinders as well as random misfire. I'm thinking I'll swap it over to the opposite bank to be safe.
I know it's possible the a single bad ignition coil can cause the random misfire code, but would it be possible a single one in a certain cylinder throw a code for a different one?

 

That is a box that holds relays. Sometimes you will hear them open and close. Odds are the ticking you hear is just to the left of it, there is a purge control solenoid. It is known to tick/make noise. It doesnt cause any issues, it just is noisy. Mine has been doing it for nearing in on 600k miles now. Its most noticeable when the temps are below 50.

 

Personally, I like to swap the coil to one cylinder and the plug to a different one.

 

[QUOTE=fsttyms1;14370 is a box that holds relays. Sometimes you will hear them open and close. Odds are the ticking you hear is just to the left of it, there is a purge control solenoid. It is known to tick/make noise. It doesnt cause any issues, it just is noisy. Mine has been doing it for nearing in on 600k miles now. Its most noticeable when the temps are below 50.[/QUOTE]

I can feel the ticking on the top of the box.
Everything seems to be running right so I'm not too concerned.


Put on about 150 miles since i cleared the code, with plenty of warm starts, still no code, which isnt surprising as I went 1k+ between last time. I just want to get it figured out and fixed already lol.
I have tons of other maintenance I don't have cash for so I'm hoping this doesn't turn into anything serious lol

 

Well, these lovely codes came back with hot starts now. Which is making belive it's from the crappy winter fuel! But something has me concerned. Since getting the codes again, I swapped Cyl 4 and 5 to cyl 2 and 6 respectively. Just had the CEL come up again, and codes were:
P304
P305
P306
P300
And Pending Fault code of P1399
So P1399 is a new code, and moving the coils didn't resolve the misfires, but I added one on cyl 6. Makes me believe the plugs in 4&5 are now bad, but I wonder why the coil moved from cyl4 to 2 didn't throw a code. And if the bad coil moved from 5 to 6 is the only bad coil, why was I getting and still getting P304? And why is P1399 now popping up as pending? What exactly is the difference between P300 and P1399, they both look like just random miss-fires.

Thanks!

 

Just when I think my daughter's car somehow cured itself, it comes back with the same old problem. It acts like yours and some others who have described similar symptoms. It's now done it twice while I've had it, so it's more important this time. Now it does it if you let idle for a long time. Now it's doing it in 30 degree weather! I'm still convinced it's fuel boiling. I was going to put on a cheap ebay fuel pressure regulator, but it only worked a little bit with the adjustment screw bottomed out. I'm going to order the updated oe style regulator from rock auto. I've got her scheduled for next week. I'll post something if it works. If you don't have a hard misfire you can feel at idle, or under accel, it's hard to isolate a coil or plug on hondas. Their misfire detection system works fine, but it doesn't identify the cylinder consistently like other manufacturers do.

 

Yeah, this seems to be a rather common and nagging issue to say the least.

Just wondering if it's something with a leaky fuel injector or a ECU signal to it ??? Maybe an iffy sensor somewhere giving poor info.

 

P1399 is a Honda code for random Misfire Same as the generic P0300 code.
I doubt its the winter fuel the ECU should be able to adapt to it.
Try whats on this video it might help you pin point the issue.
If still check all the coils for Carbon track on the boot, what may appear like a good coil throwing spark, carbon track makes it misfire. Let us know you find


Heres the example of carbon track so you'll know what to look for.

 

Haven't had the time to check for "carbon track", but I did try pulling the coil wires. I was not able to tell if there was an idle drop on any cylinder, not in the slightest. Don't quite know what to make of that. I know I'm not deaf or blind lol.
I was reading about the heat soak issue, and besides the expensive fix, it was suggested to turn the ignition on and off a few time to allow the fuel pump to run, helping get fuel to where there was vapor. So after driving a while, doing a hot start and having the issue of rough idle on start up, next time in the dame trip with car still hot I tried it, and what do ya know, no rough idle on startup.
But I am still confused as ever about the misfire codes, how they stayed on 4 and 5 and moved to 6, and also how now I am not getting codes with no issues, but now getting no codes with rough idle.
Don't know what to try next. Don't wanna throw money I don't have at the moment at plugs and coils if that's not it. It seems to run smooth but gas mileage could be slightly better on the freeway, I get what I expect with my led foot in the city.

 

Based on the date posted.. it seem to happen in the winter..??

I just begin to have this symptom also, if you clear the misfire code and if it does it again, scanner will list either more or less on misfire codes.

I never have this 'hot start' issue happen to me before till recently, but am gona try different gas station and see, or get all new coils, but don't want to throw $ at it just yet.

 

Perhaps the fuel injectors are leaking or maybe the FPR or main PGM relay is on the edge ?