ecotec missing under acceleration

[reegan89]

hey

i have recently changed the plugs and leads on my manual vx commodore and since i have done this it misses when accelerating at low revs. i found another thread of the same thing but it had no answer. have checked they are all in the right order n are on properly. any help please?

thanks

[vtanthony]

have a look at night i bought some new leads once and one of them was faulty you could see the lead arcing right down to the spark plug run the car and rev it a little

[vn_v6]

hmmm you put all the washers on the plugs?? maybe its leaking compression, check each lead inside on both ends, the little metal clips inside may be bent or covered in something, does it miss on idle aswell??

[reegan89]

hmmm you put all the washers on the plugs?? maybe its leaking compression, check each lead inside on both ends, the little metal clips inside may be bent or covered in something, does it miss on idle aswell??

nah it doesnt miss on idle. only while driving. il recheck all the plugs n leads tommorrow arvo

[wortus]

check that you did not crack any plugs and resistance check each lead.

[reegan89]

check that you did not crack any plugs and resistance check each lead.

if it was that wouldnt it miss when i rev it in neutral?

[vtanthony]

hmmm you put all the washers on the plugs?? maybe its leaking compression, check each lead inside on both ends, the little metal clips inside may be bent or covered in something, does it miss on idle aswell??

you have a point there if u put the plugs in almost cross threading them air can leak out of the plug u put in wrong

[wortus]

you have a point there if u put the plugs in almost cross threading them air can leak out of the plug u put in wrong

Aren't these plugs a tapered seal so no washers? The plugs with washers that I have seen the washers don't come off.
Threads are either cross threaded or not can't be half and half.

[wortus]

if it was that wouldnt it miss when i rev it in neutral?

No treally because th eengine is not under much load. I had a lead go on my VN and it war running OK, sometimes a bit hard to start other times it started ok and idled and reved in neutral ok it wa sonly under light acceleration up a hil it began to miss and it turned out to be an open circuit spark plug lead. The voltage on the coils is enough to jump the gap inside the lead and the plug when there is no load on the engine. Take the leads off and check with a multimeter ther eis a max resistance as well but not sure exaclty what it is off hand.

[dunky]

Usually a miss under acceleration or uphill (ie under load) is a coil

[reegan89]

FIXED

thanks for the help guys, it was a dodgy lead... wasnt connecting to the plug properly. only found it cus there were marks where it was arkin out lol.
thanks heaps.

[andy_man343]

I was wondering if anyone could please help me! i am about to blow my car up! Iv replaced all the plugs and leads today i put my mates coil pack on mine (he has the same engine) and it continues to miss. Only under slight acceleration or just sitting on say 70ks in 4th or 5th (manual gearbox) It is fine idling or when i get up it but it jumps around if i just sit on one speed or lightly accalerate. Its driving me insane!! please help. thanks

[acarmody]

Borrow your mates MAF sensor, IAC valve and TPS sensor. Last two are two sensor on throttle body and only have 2 screws apiece holding them on, and come off without removing anything else. See if that fixes the problem. If it does replace one at a time with your ones until you find the culprit. If it doesn't then replace with your parts and get a error code check done on car. Most auto sparky's I've been too have down it for free.

[andy_man343]

ok thanks mate il give it a go. Il let you know how i go..