Jerking Feeling

Hi There, sounds awfully like either crook ignition leads or spark plugs to me, if it does it when the car is under load (ie up hills or when accelerating) and doesnt do it when you back off thats my bet.

GT

 

Dfi

ive had this problem myself with a vr and a vn. always been one of a couple things. like stated spark plugs or leads. also DFI module. maybe even worth checking the coil packs.

cheers

 

same problem - what was solution?

I've got a very similar problem - but only when warm (driving 30 mins or more) and only when going up hills. Please tell me what your outcome was. I'm worried it's a big tranny problem. Holden shop tested leads and said they were fine, they replaced plugs - no difference.

 

OK, lets clear some ideas out to start with, Besides the description of the problem being really crap.... If any part of the high tension side of the ignition system was at fault then the problem would be most apparent when accelerating or the motor is under load regardless of speed.
If the low tension side of the ignition system was at fault, it to would be apparent over all speeds, not just at highway cruise.


Best bet is that the injectors may be dirty and/or the EGO is giving poor reading. The ECU is hunting for its cruise Air / Fuel ratio once you hit highway speeds. The ECU moves through its fuel and ignition maps constantly trying to reach its target but if some of the injectors are blocked and not spraying or flowing properly then it causes bad burn and crappy EGO readings.
It can be confirmed by yourself but does need good knowledge of the OBD system.

 

I'd be looking more at the transmission and whatever locks the torque convertor solid when in top gear above 80kph - if this is playing up it can cause the problem you describe by locking and unlocking. Re the key not reacting sometimes when starting - mine has always done this if it doesn't start first turn and I've figured there is a builtin delay to prevent you actuating the starter before the motor has stopped (or something similar). Maybe oil pressure has to drop to zero before you can try to start again. Ignition or ECU probs would (I imagine) be evident in other gears and speeds.

 

The general fault with the keys is generally a low battery. it did it on mine all the time, as time went on it got worse to the point where i would have to try 4 or 5 times to get any starter motor action. Got the key replaced at holden for $60, havnt had that problem since. This will start to be more common on VR-VS as they are heading to 10 years old +. Its also more common on lower KM cars (told this by holden dude) because the key is used less frequently or for shorter trips the battery tends to die quicker.

 

Feistl - hadn't looked at it from that angle though I'd have thought the first sign of a problem with the key battery would be poor operation of the remote central locking but I could be wrong.

 

I had the same problem which appeared more often than not at highway speed.

Cruise on 100km/h it felt like the road was rough all of a sudden when in fact it wasn't.
I replaced every bloody thing, and whatya know, last thing i replaced was the spark plug leads and problem was solved.

 

The key is not the problem. once the car is stared then the security system is disabled.

The torque convertor lock-up works in both 3rd. and 4th. gears.



The engine sounds like its "HUNTING" while in ECU cruise mode.

 

RE jerking / vibration, mine does it only in low and only when a good foot full is given but in second even flat out it does not do anything but GO well.

If driven normally there is no vibration in first.

Any ideas ?

 

digisol - that jerking/vibration in low is common and nothing to panic about...just live with it as trying to smooth it out will cost big dollars - I've never been in one that didn't have that roughness in low.

 

hmmm not tire balance? when i got mine it was a little shakey at 100kays but if you took it over 120, steady as a rock, and lower speeds didnt notice it.

but the only "rough" issue i get is if i cruise at 80 then gently try to bring it up to say 100 the tranny makes a rumble type noise before it decids to click back a gear and then go normally. always at 80. anyone know why? [ cars due for a service so ima do tranny but not sure if thats the issue ( filter / oil ) ]

 

yeah my VN did the excact same thing at 80k's when you went to slowly speed up a little to 100. now my vp does it at 100 if you goto speed up?

 

Does it feel like its dropping a cylinder or its just vibrating like hell? My VP does exactly this but its sounds like its dropping a cylinder, but only if you give it heaps from a standstill (does this up to around 3800rpm). Fine if you drive normally though

 

Epic thread dig. Dude was asking for any ideas in November 2005. Classic.

Thread dig of 2012, and 2012 is two days old !!!!

 

That thread dig deserves a trophy.

Also did anyone else read the title and not think its about cars.....or is that just me :whistling

 

+1 For Epic Thread Revival of the year !!!!