143 replies to this topic

[Dan r]

Thanks vocky, all things that have crossed my mind but good to hear someone with more knowledge suggest them. The fuel filter is only a couple of years old but easy enough to replace so will get on to that. Without a flow rig I can't see how to test the injectors, does anyone have one or a set I could try? They are a dark blue colour from what I can see, do you not need injector correction codes or trim numbers when fitting new ones? I'll get a borescope up the exhaust which I should be able to get hold of during the week. So the throttle body on mine is a standard na z22se one? Should make it easier to find a spare, does anyone have good one of those I could try please?? Thanks again, Dan

[CHILL Gone DUTCH]

Could this be a cracked head From over tightening the plugs

[haggi961]

could it be a misfire check because of the ecu which can be switched off with the Dutch software?

[PaulCP]

Dan, just thinking out loud Not sure a collapsing cat would cause a misfire (wouldn't it normally result in reduced power?, but the misfire could be the beginning of the cat collapsing due to unburnt fuel entering the exhaust. Cat is a Tullet 100CEL 2009 vintage Injectors could be a possibility EGR valve? Vacuum leak? Throttle body I think is standard

[Dan r]

Thanks all. EGR has been blanked I think the cat is a long shot as it hits the misfire very suddenly, although I'm not sure it feels as quick as it should under 3.5krpm, worth a look see. Got a fuel filter which I'll fit one evening this week to clear that up Checked the hose to what I guess is a fuel pressure regulator to manifold which is fitted well but haven't removed and tested the hose so will check that, are there any other vacuum hoses? Unfortunately I haven't got the dutch software and the misfire started before I touched the spark plugs. Paul, do you know the spec of the injectors so I can try and find another set please? Thanks again, Dan

[Nev]

It might possibly be that your fuel pump is getting tired or can't draw enough current.

Edited by Nev, 31 May 2016 - 07:01 AM.

[PaulCP]

Dan, I think they may be Astra VXR injectors but Jon will be able to tell you if its not on the paperwork

[fezzasus]

simple test for the injectors; if they're baby blue with EV1 plug then they're VXR, black with EV1 then they're turbo.

[Dan r]

Injectors are a very dark blue, the connectors are black which highlights this, so I assume they're turbo ones but will check. There's a mention of injectors in the file but not the spec. The fuel pump is only three years old so not likely to be that but won't rule it out. Just ruled out the fuel filter as fitted that and made no difference. I held it on the misfire for a second this morning and it really stinks of fuel so would imagine its spark related (I'm confident its not just one cylinder at fault as it feels too harsh like a rev limiter) also the live map channel on my scanguage holds a constant of 14 ish at 3.5krpm wot so there's no sudden boost leak. Can anyone tell me if this is in the right area please? I don't seem to get a second to think during the week so keep forgetting to call jon at Courtenay's to discuss which is frustrating! I may discuss sending the ECU back so he can check it over. Thanks again for the help guys.

[vocky]

what about the spark plug electrode gaps ?

 

might be worth closing the gap up to 0.8mm

[Dan r]

I set those to 0.7 which I thought was the correct gap when I fitted new ones which didn't make any difference.

[PaulCP]

Dan, you say the misfire is like hitting a Rev limiter, does it happen at exactly the same rpm every time? A little off the wall thinking but I wonder if the alpha box for the change lights is causing a malfunction. Not sure how it would link to the problem but when setting it you use 50% rpm. Could be worth disconnecting it?

[Dan r]

It's not quite repeatable to 3.5krpm, I managed to get to about 4.1krpm on part throttle and get full load for a second before it misfired. It runs badly unless it drops back near to idle then it seems OK again, very odd like a valve is stuck open which won't close until engine speed drops. I removed the alpha box and replace it with the one from my old blue one which is an I shift I think. No harm disconnecting it just in case I suppose

[Dan r]

...it does misfire under part load around 3.5krpm though

[CHILL Gone DUTCH]

If it stinks of fuel its running rich Does the exhaust give a little pop when you switch off So causes fuel not igniting or to much fuel Spark plugs Coil pack Possibly ion sending picking up somthing high temps ? Is your charge cooler working ? Lambda sensors Correct injectors from mapping ?

[Dan r]

If it stinks of fuel its running rich Does the exhaust give a little pop when you switch off So causes fuel not igniting or to much fuel Spark plugs Coil pack Possibly ion sending picking up somthing high temps ? Is your charge cooler working ? Lambda sensors Correct injectors from mapping ?

My previous sc vx and this one has always done a little pop when switch off and never had issue before, it only smells of fuel, when it misfires, other than then it runs perfectly. Coil pack replaced, injectors have always worked perfectly before, lambda sensor would show a fault codes surely? What do you mean by ion sending? The fault happens the second the revs rise to around 3.5 krpm particularly at high load even when the engine is still warming up so intake temps wouldn't have chance to get too high surely? There's only a map sensor as far as I know so have no way to check this? Bit odd there isnt a temp sensor in the manifold as well? I'll check the coolant flow in the tank but other than that is there anything else I can look at? Thanks Dan

[Dan r]

Coolant flow is all good.

[haggi961]

Normally the limp mode is caused by the misfire check. For power levels above 250bhp, it is pushed outside its limits and ECU thinks the car is misfiring and goes into limp mode. With the Dutch software you can disable the misfire check and you will have no problems.

[CHILL Gone DUTCH]

If it stinks of fuel its running rich Does the exhaust give a little pop when you switch off So causes fuel not igniting or to much fuel Spark plugs Coil pack Possibly ion sending picking up somthing high temps ? Is your charge cooler working ? Lambda sensors Correct injectors from mapping ?

My previous sc vx and this one has always done a little pop when switch off and never had issue before, it only smells of fuel, when it misfires, other than then it runs perfectly. Coil pack replaced, injectors have always worked perfectly before, lambda sensor would show a fault codes surely? What do you mean by ion sending? The fault happens the second the revs rise to around 3.5 krpm particularly at high load even when the engine is still warming up so intake temps wouldn't have chance to get too high surely? There's only a map sensor as far as I know so have no way to check this? Bit odd there isnt a temp sensor in the manifold as well? I'll check the coolant flow in the tank but other than that is there anything else I can look at? Thanks Dan

Ion sensing http://www.delphi.co...ignsys/igncoils The popping is a sure sine the car is running far to rich Take a pic of your spark plug and post it please Injectors can fail and dump to much fuel in That popping is not a good sign and you may end up bore washing the cylinders A faulty lambda will give the wrong info and can cause rich running or Lean running Lambda do fail on supercharged cars

[Dan r]

Never heard of ion sensing, been working on mucky diesel engines too long! Interesting stuff. Will sort a pic of the plugs but I'm pretty sure they look OK. Thanks