VN Commodore S suddenly running ruff

[jakewaze]

Hi
Last night a brought a 1990 VN S auto in awesome condition with bout 2500000k's and it ran really well.
This arvo I went and filled it up with fuel and put in some injector cleaner in aswell and then started it and it was idling like crap and didn't feel right when cruising.
any ideas wat it is and how to fix it

[Morton]

idling "like crap" eh? Spluttering up and down, or just rough in general?

Rough always, or rough only at idle?

Try unplugging your injectors one by one and see if any of them make no difference.

Take out your spark plugs and see what stories they tell.

Change the damn fuel filter, it could be blocked up like a bitch.

Then see what happens Actually, start with the fuel filter.

[goat]

check that all the vacum hoses are on properly too

[Eliminator]

i would start off with a full service including plugs, leads, oil, air/oil/fuel filters then asses the car from there, might iron out the problem for a cheap & easy fix...

[Morton]

Been a week since this bloke posted now. I can only assume his car blew up and he's dead.

[crazybiker]

Aren't you a nice fella morton?

[Morton]

You know, that's the first time anybody's said that about me. Thankyou

[crazybiker]

I'm glad I made your day.

[Daniel.B]

I'm in a similar boat, just brought a VP series 2 exec, also mint condition, ran well well i got it, apart from a slight missfire when idling. I also added a bottle of injector cleaner with a full tank, and at the same time changed all my filters, plugs and leads, and oil. Ran fine, same slight missfire, but since gotten a hell of a lot worse. Idles something shocking, shudders makes knocking noises, is hard to start, and stalls in park/neutral and is just a nightmare unless your accellating in gear. Is it possibly somehow linked to the injector cleaner...??

[89berlina]

Been a week since this bloke posted now. I can only assume his car blew up and he's dead.

lol Dont you love that. Most of the time I come across threads on this site where someone mentions a problem and asks how to fix it and they're given advice, by loving members such as Morton but you never hear from them again. At most times I read through the threads to diagnoise my own problems but always disappointed to find no ending to a thread. These thread wasters are most definitely doomed to have they're VN's explode

[goat]

I'm in a similar boat, just brought a VP series 2 exec, also mint condition, ran well well i got it, apart from a slight missfire when idling. I also added a bottle of injector cleaner with a full tank, and at the same time changed all my filters, plugs and leads, and oil. Ran fine, same slight missfire, but since gotten a hell of a lot worse. Idles something shocking, shudders makes knocking noises, is hard to start, and stalls in park/neutral and is just a nightmare unless your accellating in gear. Is it possibly somehow linked to the injector cleaner...??

lol funny you should say that..atm my VS is running like crap with the same symptoms..spark plugs/leads all good and checked..swapped over coil pack no difference..changed fuel filter, check vacum hoses and even chucked in 2 new inlet manifold gaskets...started her up and still runs like crap! and it all seemed to get wrse after i ran some injector clean through it...i pulled off injectors one by one to see if i could a hear a difference nothing..im really stumped >< we're all doomed!

[goat]

error codes gath nothing either (as usual) lol... i'm about to cry, im a poor student and cant afford the "fun" of an old commodore any more...is it possible the O2 sensors or maybe the crank angle sensor could be causing these issues??

[Daniel.B]

So i guess i shouldn't add anymore injector cleaner then huh ?

[Morton]

Injector cleaner is great stuff. I use some every month. I suspect this bloke put too much in, and dislodged a whole bunch of crap into something it didn't belong in ^_^ HIs fuel system was probably filthy, and now his injectors are clogged

[goat]

hmm..nah i only ran about half of what was recomended for a tank...but on closer inspection of my oil today noticed it was a poo brown as in "blown head gasket" poo colour... great, back to pulling apart that ecotech again lol

[jakewaze]

Sorry i haven't replied guys. Thanks heaps for the advice but it turned out to be a loose lead. I feel stupid now lol.

[goat]

wish that was what all mine was..well i guess i'll find out once i pull everyhting out..

[Morton]

Sorry i haven't replied guys. Thanks heaps for the advice but it turned out to be a loose lead. I feel stupid now lol.

I can understand you not wanting to reply and tell us