misfire at high revs in neutral

[neilk]

Hi when I am in neutral and floor the excellerator pedal I get a slight hessitant misfire, and a little bit of smoke, also when I start up from cold it runs lumpy, and the same sort of smoke is omitted, any ideas please:bow
Neil

 

[jims-terrano]

When was the last time the fuel filter was changed? is there air getting in to the system perhaps?

Have you noticed anything whilst driving it? might be one of those things that is best left if it's not causing you a problem perhaps?

Jim

 

[clivvy]

I'd check fuel filter like Jim says. Also air filter (before I changed my air filter, i got the same effect when flooring it in neutral). I had a similar issue to that which you describe, but i had many problems to fix, so here are soem that may be related:

No1 Injector - affects timing as well so check the codes perhaps?
Air filter - replaced with K&N, massive difference
Fuel filter - change or at least drain via tap-see downloads section
MAF - may explain the smoke, remove it and clean it, i simply left mine to soak in some electrical contact cleaner, seemed to work.
Earth wires from engine block to chassis-mine were corroded but wasnt obvious-check them for rubbing against chassis.
CKP sensor - again, check codes, it MIGHT be on its way

think thats it? may be non of the above, but worth looking at, reading the codes will help a lot...

good luck!

 

[Timbo_1975]

Hi when I am in neutral and floor the excellerator pedal I get a slight hessitant misfire, and a little bit of smoke.

You wil never completely cure this, it is a peculiararity of the factory ecu mapping.

also when I start up from cold it runs lumpy, and the same sort of smoke is omitted, any ideas please?
Neil

Probably you have one glow plug out, so she is firing up on 3 initially.

 

[DEE]

O i

I am with Timbo 1975 on this one. Did all the checks on my old terrano. New maf New injectors All the filters Bla Bla Bla And it still did it All the same as yours. on start up and flooring it Backing up it did it, Rev it up slow and it never missed a beat, Floor it, shake shake shake, No not your body :lol I have a 05 plate that does it a little, But that is the only prob, So i can live with it . After owning a shogun sport if the terrano ran on 2 And on three wheels it would be better than one of themm pile's of pooooooooooo If you do sort it let me no. Good luck :thumbs

 

[clivvy]

I dunno guys, i think its sortable, like i said earlier, mine did exactly that, and now when i floor it in neutral it goes all the way past 4k revs perfectly (as it should). I do wonder though, if the cause is No1 injector? Not sure how long they are supposed to last, but seems to me they conk out at around 115k miles ish, so perhaps a build up to it conking out is this sort of issue.

 

[briggie]

i always put some redex injector injector cleaner in every 2 tankfulls

 

[neilk]

Thanks guys, theres useful info there. I think I will check out the plugs first as she seems to run ok.Fuel consumption good :28/29 combined , so i dont think there is to much to worry about
Neil

 

[Trigsbroom]

Without wishing to take the piss, I can't help wondering why you'd want to floor the throttle in neutral. What can be acheived from revving a lazy, heavy flywheeled diesel?

 

[DEE]

Without wishing to take the piss, I can't help wondering why you'd want to floor the throttle in neutral. What can be acheived from revving a lazy, heavy flywheeled diesel?

As i have had my say on this matter. Trigsbroom. Your right its not a good idea to rev the conker off the engine in neutral. But i only picked the matter up on my terrano when it went in for a M/O/T And the M/O/T man floored it to check the C02. Thats when i heard mine missing. So yes good point dont floor it in neutral. But they do on the m/o/t

 

[Trigsbroom]

Got it!:thumb2
If they floored the throttle on mine during MoT, I'd floor them!:lol:lol

 

[neilk]

I didnt rev it, i took to my friends company underbody protection to be undersealed, and being a mechanic i asked him to give it the once over before the mot and he drew my attention to the misfire