Cel on Code P0303
 

Hi
We had the cell light come on a few weeks back and had the local Honda Dealer do the code check and ECU Re-set.
On this Occasion the code was P0303 a misfire on Number 3 they gave it back to us but the light came on again so it is back in.
OK having read the posts in FAQ it would seem that if it comes up with the same fault this time i have a component failure on No 3?

My Questions are as follows

It would seem that it could be coil pack (are these one per plug?)
Plug
Valve issue clearance maybe? (are they checked as part of regular service?)

I hope to have some more info later from Honda but interested to hear if owners may have had simliar problem

Cheers Liam

Not uncommon.

One coil per cylinder.

Really tricky to diagnose ove the net but it could be:

Plugs / Injector / Coil Pack / Lambda / MAP / Crank sensor / Engine problem

One tactic is to replace the plugs and then swap coil packs around to see if the fault follows to another cylinder. Same with the injectors if that doesn't work.

Some other tips in the link at the bottom of my signature.

Can be valve clearances and these are checked on some of the service intervals.

There are very recent posts on here along similar lines. Coils, injectors etc all possibles and first place to check.

Ok The fault code shows No 4 now so not likely to be one plug or coil
Honda are doing the valve clearances as i type to see what we find!
I have asked them to note the existing for my reference.

Liam

If its moving between cylinders you can nearly rule out the plugs / injectors / coils and concentrate on other stuff 1st. Of that lot i'd say injectors are most likely.

It now looks like a common type fault.

Valve clearances if they will do it.

See if it comes back.

If it does you have to start looking at the things common to the ignition system (map / lambda / ECU wires etc)

OK the update is that Honda checked all the valve clearances.
The Exhaust valves where all tight (not good)
My wife reports the car feels so much better on the road so i hope this is the cure!

As a point of interest the car was recently on a Rolling Road and was 30 odd BHP down on the book figure.
If the clearances were tight i am guesing the valves may not of been fully closing when hot so it could help explain the low figures??

I intend to Roll the car again soon to double check!

Thanks for your feed back guys and i hope we have the cure.

Liam

Correct and good work!

Be very interested for you to report the RR figures back on this post.

I aim to Roll the car soon and will post the results hope to find nearer the book figure.
In the mean time the car seems much better so hope it stays tha way!

Liam

Ok the Issue with the car continues.
The car ran great after the valve clearences were done and on the Dyno a small inprovement too but still low compared to book.
The car gained 5% 10 BHP but still only delivers 212 BHP

The real problem is the return of the Misfire on No3 fault Code!!
Last week it started running poor again i called the RAC to find the fault code was again No3 Misfire
This time i decided to do some ground work
Full compression check showed no issues around 200 PSI all around
So then i figured to do what HONDA have not!
I swapped no 3 coil pack for no1 and ran the car it threw the light again.
I had the code checked again to find fault on No 3 Still!!

So i have moved No3 plug to No1 to see if that moves it??

The question is what else could be causing the No3 misfire code
Supply to ingnition coil No3?
Injector Issue?

Going to have to go back to Honda and try to resolve this.

Thanks for reading the post and for any help you can offer

Liam

Injector is quite likely given you have eliminated other options.

Apart from swapping them, someone recently suggested you can measure the resistance with a multimeter, but I didn't really investigate as to wether this was a valid test or not.

I'd just swap it with number 1 and go from there.

Good to see you have done the obvious and tried plug / coil pack swap.

If only everyone were like you!

:iagree: Also bad cable Connection's on the injectros can cause all sorts of problems, so you can check this when removing :)

I took some time to wiggle the connections all around removed the injector plastic cover and worked the wires. I have been tring to get to misfire and idle rough, i figure if it runs poor on idle i can pull the injector plugs off and see if i can norrow it down!
Are injectors a problem on S2K or is the plug the problem. My concern is Honda Techs seem useless at getting the fault fixed.

Liam

Not at all, well no more than other cars, you can remove one at a time and check them but your waisting your time here as the problem sounds like a intermission electrical fault with the injector itself, you can remove the offending one and swap with number 1 reset the ECU and that will soon tell you if the injector is at fault, as Mark said !!

OK i can look at the swap how do i clear the ECU each time is it a power off job??
Also is it possable to fual code read DIY as getting the codes read can be a pain The freindly RAC guy has plugged in for me but a cant keep calling them LOL

Cheers Liam

Try the facts fella, as it explains what happens when you do a reset and i think you should know the facts:

https://www.s2ki.com/forums/index.php?showtopic=301506

Its about quarter way down the page. You will need a code reader again as if the fault is with the injector it will come up with number 1, well with any luck :)

PS a local garage will have a code reader!!

Liam, injector problems do seem to be very common on the S, I rarely hear of them on Scoobs and Evo's for example. A lot of the time its a build up of crap and they can be cleaned.

ECU reset can be done via pulling a fuse down by the drivers side panel, or disconnect the battery for 10 mins.

Once it's reset it will need to idle for 5-10 mins to reset the idle learning.

If you want your own fault reader you can buy them online / Ebay. I'd go for a Geniscan GS300 for about

And here's one:

http://cgi.ebay.co.uk/Autel-Geniscan-GS300...7QQcmdZViewItem

Or you could try Veehexx's way:

http://www.modifry.com/freebies/old/dtc/index.htm

Well i have pulled the injector from 3 and put in No1 so now wait for the cell or misfifre to return.

I will check out a reader as it cost me 35 quid for Honda to diagnose and read.
As you say other cars dont suffer my Evo has never missed a beat i cant recall std injectors ever being an issue.

Thanks guys for your pointers

Liam

my sig is useful!! :)

injectors do seem to be fairly common place, but you've swapped 'em around and waiting to see what happens.

hope the injector swap shows something positive. i know what it's like to have an annoying misfire and your checking everything to see what it could be

veehexx i hope to find the fault has moved with the injector to No1 fingers crossed.I will try your system as it covers the codes i have been getting.
Also looking at buying one of these scanners could be a good investment
I have cover on the car but it only pays for repairs not diagnostics so i dont mind finding the fault and spending on the repair just need to get to that point.

Cheers Liam

I posted a while ago i had an injector problem on my CTR, started as an intermitant misfire.Eventually at high RPM the output transistor for that cylinder blew causing the ECU to be US.Problem was a faulty injector giving a high resistance eventually backfeeding to the ECU at high RPM blowing the output transistor.
A quick resistance reading of the injectors one by one revealed the problem.Replacement injector and ECU (keys recoding also) and all was fine.

AL do you recall the details for checking the resistance ie where to take a reading and the range they should run in??

Cheers Liam

Liam, i cannot remember the actual readings, it was about 2 years ago.The faulty injector was obviously different to the other 3 injectors.

You can check the injectors in place, all you need to do is unplug the wire harness connector and take a resistance reading across the terminals.Obviously they should all be a similar reading, mine was very obvious, infact i still have the faulty one somewhere and have 3 spare 'good' ones.This remember was for a CTR, not sure if the injector spec is the same for the S2000?

OK so this topic is live for me again after weeks of good running this morning the car started rough and threw a cell light.

Having taken some advice i now own a fault scanner (been sat there weeks waiting lol)
Plugged it in to find the same old Code P0303
So having moved the injector and coil to another cylinder i feel it is fair to say the fault is not those components.

A wiggle and pull off the injector plug gave good running this morning but i can get the fault to repeat whilst playing under the hood.

So the question i have is what else can be checked do the injector plugs or loom give issues? or the unit that controls it all the ECU?

Advice is all welcome and thanks for that given so far!!!


Cheers Liam