Misfiring + Engine Light

[jesus]

I know there's plenty of threads on here but I've never seen one with the engine light flashing (amber) before.

The misfire just started all of a sudden but went away once the car had warmed up.

After cooling down and driving it again, it's still misfiring but even when up to temperature now.

The engine light flashes amber but sometimes goes off and comes back doing the same thing later.

I replaced the coil pack not too long ago.

Any ideas of how I can check what's up with it without getting it plugged in? I only ask that because I need the car for work!

 

[JaredHasNoBrain]

HT Leads and plugs is what i'd check

 

[jesus]

How do I check if those are the problem?

 

[rdoxenham]

I had this, it was a faulty injector. It would be absolutely fine one minute and then misfire constantly the next (with the engine light flashing). Plugged it into the fault code scanner, told me which cylinder the misfire was on and replaced the injector. Not had the problem since.

Cheers
Rhys

 

[jesus]

Cheers, I'm hoping it's not as big a job as an injector though. Are there any other checks I can do to diagnose the problem?

Could it be one of the leads or even the lambda sensor?

 

[JaredHasNoBrain]

I plugged mine in into a OBD reader from Ebay or somewhere for cheaps, Told me which cylinder was missfiring So, Just to be sure for future I got some new spark plugs and Sharkeys Coilpack and Simons HT leads lol

 

[Poopensharten]

Tried disconnecting the ht leads one by one whilst its running and listening to the engine?

 

[jesus]

I've not tried that yet - what would I be looking out for and how would I know if one was faulty?

 

[bright]

The flashing light iirc is indicating a destructive miss fire.

I had it when my coolpack failed, and when ny leads were shorting on water in the spark plug area.
If you've cleaned the engine bay recently, first thing I'd check is if theres anything shorting.

A not bad way to do this is to start the car up in the dark and look for any random flashes.

Injectors are also a possibility. Testing for injectors (once you've ruled out spark plugs and leads) is to remove the fuel rail protector, and then just unplug one injector at a time until you find one where the engine note doesn't change.

 

[jesus]

I have cleaned the engine bay but only where the strut tops are. The water did dribble down but drained out near the wheel arch area.

Thanks for the advice. If I'm testing for leads, do I unplug them from the coil pack or at the other end?

Also, how do I unplug the injectors? I've never seen them before so don't want to mess anything up! Are they easy to swap?

 

[Gibbo4k]

mine did this a few months ago and the reader said cyl 2 missfire. turned out to be an injector . id already changed coil/leads/plugs. new injector was under 30 quid and is easier to change than the plugs.. if you do get the code read and it tells you which one it is number 1 is the gearbox end which confused the hell out of me until i was told..

 

[The Fatty]

I have cleaned the engine bay but only where the strut tops are. The water did dribble down but drained out near the wheel arch area.

Thanks for the advice. If I'm testing for leads, do I unplug them from the coil pack or at the other end?

Also, how do I unplug the injectors? I've never seen them before so don't want to mess anything up! Are they easy to swap?

Checking the injectors is pretty easy; simply unplug the electrical connector for each injector one at a time whilst the engine is running (the electrical connector has a metal bit you push in first, then it just pulls off). Changing an injector is easy as well, unscrew the 2 bolts holding the rail on, disconnect fuel rail and then just pull the whole rail forward. All 4 injectors will just pull out of the manifold. Take the clip of the faulty injector, replace with new one and reverse the above. Its about 5mins work to make sure its actually an injector that's failed, do the above but instead of using a new injector, just swap 2 around and see if the fault move to that cylinder when running.

 

[jesus]

Thanks for the help, very useful should I have to do the job.

Checking the leads, do I pull them out of the coil pack or the other end?

 

[The Fatty]

coil pack end. other end is under the manifold. tbh your better off checking the injector first, as pulling the HT lead off wont tell you if its the lead or the injector, but the injector test will.

 

[jesus]

Right I'll go and have a look. Thanks a lot

 

[The Fatty]

be careful when taking off the fuel pipe from the rail, it sprays fuel out like a b**ch sometimes. Put a rag around it to stop it spraying back onto you.

 

[jesus]

Ta!

Had a look, when I unplug each injector the car engine revs lower... except when I unplug the 3rd one from the left when it does nothing.

Does that mean that the 3rd one's knackered?

 

[The Fatty]

it mean the problem is on the 3rd cylinder. What you need to do now is check if its the injector or coilpack/ht lead. To do this, remove the fuel rail as described above and sway injector 3 for injector 4. then put it back together and do the same unplugging the electrical connector test again. if the 'no effect' has moved to cylinder 4, then its the injector, else its the Coilpack/HT lead/spark plug. remember injector 1 is at the gearbox end and 4 is at the timing belt end.

 

[jesus]

How do the injectors come off the fuel rail? I can see a little silver metal clip but no idea how to move it!

 

[The Fatty]

with the fuel rail removed, remove the silver clip by moving it upwards with a screw driver, then the injector will just pull out. Its takes a bit of force to pull it out once the clip is removed.

 

[jesus]

Spot on... I can't get them back in now though!

Edit: into the manifold.

 

[The Fatty]

to get the rail/injector back onto the manifold, line up the injectors with the holes and try wiggling the whole assembly up and down whilst pushing inwards. You can also use to grease to help it go in. Remember to reconnect the fuel rail before starting up!

 

[jesus]

Job done. Thanks again for all your help. The same cylinder is still doing nothing when I unplug the injectors even though I've swapped them around.
Am I alright to leave them in the 'swapped around' position or do I need to change them back?

Does this mean that it's a HT lead that's at fault?

 

[The Fatty]

you can leave them as they are That eliminates the injector, so the next thing to do is swap a HT lead over. You will have to remove the upper manifold to do this iirc as they are under the manifold. See if the misfire moves position, if not, then I would say its the coil pack or spark plug.

 

[jesus]

Do I need to swap the entire lead over or just where it goes into the engine?

Edit: just swapped one over (full lead) - car revved it's nuts off and spat a flame. Err!

 

[jesus]

Okay I've no idea what's happened but I've put everything back to normal and it's idling really high and making a strange high-pitched screaming noise. WTF have I done?! :dapprove:

 

[Poopensharten]

Re: Misfiring + Engine Light (& now noise from engine)

Sorry i never got back.. But realistically if you pull the ht leads out one by one it should eliminate the problem.

If the car was missing on cylinder 3, when you pull out another lead for any of the other cylinders the car should cut out (it'll run rough on 3 cylinders, it wont run on 2!)

​edit: i had that noise before when changing the plugs, it went away by its self!

 

[jesus]

Re: Misfiring + Engine Light (& now noise from engine)

Cheers Danny. I seem to have buggered something up whilst taking the inlet off to pull the HT leads out. I swapped one lead around with another then it revved loads, so I turned it off and swapped everything back to normal. Now something's screaming at me like in the video, no idea what it is :dapprove:

 

[The Fatty]

Re: Misfiring + Engine Light (& now noise from engine)

Christ that sounds bad! don't run it for the moment!! what did you do before this happened? did you take the inlet manifold off? Regarding the ht leads, you needed to swap the whole lead over. Are you sure you have put them back on the correct places now though? things to check begore turning the key again are:

1. HT leads are on the correct outputs of the coilpack
2. inlet manifold is on correctly
3. if you have had the top inlet manifold off already, can you confirm you didn't drop anything into the engine?

 

[The Fatty]

Re: Misfiring + Engine Light (& now noise from engine)

ps. an air leak somewhere can cause it to rev, but that squeal sounds like metal against metal on the video.

 

[jenic]

Re: Misfiring + Engine Light (& now noise from engine)

Is the o-ring thing at the back underside of the inlet manifold you removed seated correctly?

 

[The Fatty]

Do I need to swap the entire lead over or just where it goes into the engine?

Edit: just swapped one over (full lead) - car revved it's nuts off and spat a flame. Err!

this sounds like you have put the leads back in the wrong places on the coilpack. i.e. it fired to late.

 

[jesus]

Re: Misfiring + Engine Light (& now noise from engine)

HT leads are in the correct places. Inlets are on correctly and everything is plugged in and nothing fell in the engine as I kept an eye on it making sure nothing would.

I don't know where the noise is coming from but I don't want to run it long enough to find out.

It was swapping the leads over that made it rev + bang, then when I swapped them back this happened.

 

[jesus]

Re: Misfiring + Engine Light (& now noise from engine)

Is the o-ring thing at the back underside of the inlet manifold you removed seated correctly?

Just double checked and this was the problem! I'd not screwed one of the bolts in all the way (just didn't pinch it tight) so it might have been out of place a little bit. It's gone now and the revs are normal, back to how they should be (thank god!)

It's still misfiring though.

Sorry i never got back.. But realistically if you pull the ht leads out one by one it should eliminate the problem.

If the car was missing on cylinder 3, when you pull out another lead for any of the other cylinders the car should cut out (it'll run rough on 3 cylinders, it wont run on 2!)

​edit: i had that noise before when changing the plugs, it went away by its self!

I unplug the lead from the coilpack and it should cut out... is that correct? I tried that earlier and it still ran, the revs just went lower.

 

[The Fatty]

thank f**k for that! it sounded a lot worse than an air leak on the video. unfortunately what Danny is telling you to do wont tell you if it's the coil pack, ht lead or plug. As you already know its cylinder 3, its not really going to tell you anything new. you need to swap the full HT lead (both ends) of cylinder 3 for another one, making sure everything is put back correctly. This will then tell you if its is the coil pack/plug or the HT lead.

 

[jenic]

I think he's already tried changing a full lead, have you swapped a couple of plugs around?

Then I'd try another coil pack.

 

[The Fatty]

I think he's already tried changing a full lead, have you swapped a couple of plugs around?

Then I'd try another coil pack.

I think he did it wrong the first time around though as it shouldn't have gone 'bang' and blown a flame.

 

[jesus]

Yep I was getting ready to break it! I tried the leads earlier but there must have been an air leak then too (albeit it wasn't making the screaming noise, just revving higher).

Okay I swapped two full leads around. The car is running better now but still misfires if I rev it slightly.

When I unplug the injectors, every one makes the revs go lower and misfire.

Not sure what this means!

 

[jenic]

Has the misfire code changed to a different cylinder?

 

[jesus]

When I unplug the injectors they all do the same thing now.

Prior to changing the leads around, cylinder 2 was the one that when I unplugged the injector nothing would happen.

I've not had it plugged in if that's what you meant by code, I couldn't find anyone with a machine.