Technical P0300/p0303

[TobiasBB]

So, I was speeding a little bit in my 04' Climbing, and the little orange motor-light came on twice... at home i popped in my reader giving the two codes p0300 and p03002, which after a bit of googling tells me Ill need new ignition cables and/or sparkplugs, Ill swap those after work tomorrow.. but the smell of the exhaust and lag of power plus high fuel consumption indicate it might be the catalytic converter.. So with my recent luck im expecting to exchange the cat (Im thinking sports catalytic converter), and while im there ill exchange the pipe to the backbox, and that leads me to the real question; anybody on here tried the dual exhaust backbox from ulter on the climbing? Any drawbacks? Anything I should be careful of? I've never changed an exhaust before...

 

[koalar]

So, I was speeding a little bit in my 04' Climbing, and the little orange motor-light came on twice... at home i popped in my reader giving the two codes p0300 and p03002, which after a bit of googling tells me Ill need new ignition cables and/or sparkplugs, Ill swap those after work tomorrow.. but the smell of the exhaust and lag of power plus high fuel consumption indicate it might be the catalytic converter.. So with my recent luck im expecting to exchange the cat (Im thinking sports catalytic converter), and while im there ill exchange the pipe to the backbox, and that leads me to the real question; anybody on here tried the dual exhaust backbox from ulter on the climbing? Any drawbacks? Anything I should be careful of? I've never changed an exhaust before...

Nope P3002 just indicates a misfire on cylinder 3.

Doesn't tell you anything else. Not that useful of a code.


Could be fuel, ignition or compression. Along with water or oil entering the cylinder.


Once detected the ECU will stop the injector to prevent further damage thus the loss of power.


Checking the spark plugs Is a good start. Swap cylinder 3 plug to another cylinder and see If the misfire moves with the plug.

 

[Goudrons]

P0300 is a random misfire code.
P0302 is a misfire on cylinder 3.

It's not uncommon to get multiply codes of this sort, the ECU detects a misfire or two and flags the P0300, then detects repeated misfires from pot 3 so you now get P0303.
(I don't know if P03002 is a mistype?)

There have been a few of these type of faults reported on here, but they don't all have the same sources.
Ignition and fueling are prime suspects.

Though a mechanical fault such as a head gasket leak or and ECU/wiring fault isn't out of the question.

The loom in the Active models do seem to have a fault with a wiring connection that causes the same problems, might be worth a look on here as someone did find and fix theirs.

You can, with a bit of logic narrow things down a bit if you have the time and patience.

Moving parts from one cylinder to another, one at at time may help.
If the problem moves with that part, there's your culprit.

Start with plugs and leads, then coil packs and injectors.
I'm pretty sure the up and down stream O2 sensors are the same part, if might be worth swapping them before giving up, a duff up stream can cause an overly rich mixture and misfires, but it'll read like this on a diagnostic tool anyway if you have an ignition/fueling fault.

I suspect it maybe just a failing coil pack though.

Don't read too much into the exhaust smell being a knackered cat, unburnt fuel and air is passing through it, so the cat won't work properly due to the cooling effect of the unburnt fuel/air.

 

[TobiasBB]

P0300 is a random misfire code.
P0302 is a misfire on cylinder 3.

It's not uncommon to get multiply codes of this sort, the ECU detects a misfire or two and flags the P0300, then detects repeated misfires from pot 3 so you now get P0303.
(I don't know if P03002 is a mistype?)

There have been a few of these type of faults reported on here, but they don't all have the same sources.
Ignition and fueling are prime suspects.

Though a mechanical fault such as a head gasket leak or and ECU/wiring fault isn't out of the question.

The loom in the Active models do seem to have a fault with a wiring connection that causes the same problems, might be worth a look on here as someone did find and fix theirs.

You can, with a bit of logic narrow things down a bit if you have the time and patience.

Moving parts from one cylinder to another, one at at time may help.
If the problem moves with that part, there's your culprit.

Start with plugs and leads, then coil packs and injectors.
I'm pretty sure the up and down stream O2 sensors are the same part, if might be worth swapping them before giving up, a duff up stream can cause an overly rich mixture and misfires, but it'll read like this on a diagnostic tool anyway if you have an ignition/fueling fault.

I suspect it maybe just a failing coil pack though.

Don't read too much into the exhaust smell being a knackered cat, unburnt fuel and air is passing through it, so the cat won't work properly due to the cooling effect of the unburnt fuel/air.

It was a typo, see attatched screenshot.. Ill try changing the sparkplugs and leads first since they were the ones that was sitting in the motor when I bought it.. if it doesnt make the p's go away Ill try the coilpack, I think I have a few lying around the basement somewhere.. fingers crossed its that easy..

 

[TobiasBB]

So swapped cables and plugs and after 20?km no codes, and smoother sounding... attatched are the plugs, pulled in the order they are lying in from left to right. Thanks for the help in maybe not having to get a new catalytic converter just yet

 

[TobiasBB]

Apparantly it did not solve the issue... it happened again today, but only at 110kph, which could indicate fuel-starvation in that cylinder? Im thinking Ill clean/replace the injector (I have some extra lying in a box).. is that a sensible way to adress the problem?

 

[koalar]

Apparantly it did not solve the issue... it happened again today, but only at 110kph, which could indicate fuel-starvation in that cylinder? Im thinking Ill clean/replace the injector (I have some extra lying in a box).. is that a sensible way to adress the problem?

Yes its sensible. There is no right or wrong answer. Its a question of eliminating things. As you already have the parts it costs nothing.

Plugs look a good colour. But changing them helped. Suspect the coil pack is breaking down at higher revs

I would swap the coil packs over and see if the error code is for another cylinder.

 

[DaveMcT]

Ive had coil packs break down gradually and cause all sorts of issues including sooty plugs. These are wasted spark coils firing two plugs at the same time. A weak coil will favour one plug.

Swap the coil connections at the low tension (trigger) side and plug leads to the other plug pair. If the misfire moves you have the culprit.

 

[TobiasBB]

Ive had coil packs break down gradually and cause all sorts of issues including sooty plugs. These are wasted spark coils firing two plugs at the same time. A weak coil will favour one plug.

Swap the coil connections at the low tension (trigger) side and plug leads to the other plug pair. If the misfire moves you have the culprit.

I'm sure I have some lying around here somewhere, (they might be stuck on an old motor..) but hopefully no corossion, so ill swap those while doing the injector, it wont tell me what was the issue but it will take care of all the things that has been suggested..

What side does the ECU count from? Which is cylinder 1? And which is 4? I think i remember to have read somewhere the waterpump end should be the first, but I'm unsure..

 

[koalar]

I'm sure I have some lying around here somewhere, (they might be stuck on an old motor..) but hopefully no corossion, so ill swap those while doing the injector, it wont tell me what was the issue but it will take care of all the things that has been suggested..

What side does the ECU count from? Which is cylinder 1? And which is 4? I think i remember to have read somewhere the waterpump end should be the first, but I'm unsure..

Yes No 1 cylinder is at the timing belt end

 

[TobiasBB]

so update on this for googlers in years to come: as you might guess I'm not the fastest at fixing non-critical issues.. but last week it started misfiring on both cylinder 2 and 3, so the easiest common denominator was a coilpack, changed in 5 minutes and it didnt misfire a single time on my trial-run designed to have it misfire..
It freed some horsepower, all of a sudden 110kph didnt feel like top speed - it had a tiny bit more to give! -and allegedly better fuel economy...

 

[koalar]

Good to know you got to the heart of the problem and its now running on all cylinders so to speak.