Jolting at 80 -100kms

[Scott98]

I have just purchased a VT Berlina 98. When cruising along at about 80 - 100kms/hr and I accelerate slightly the gearbox cant decide if it wants to change down or not. It jolts as if it is going to change but doen't. It is only if you put your foot down further that it will change. The problem seems the worst when on cruise control and it goes up a bit of an incline. Any ideas what may be causing this?

Cheers Scott

P.S. the transmission fluid seems to be ok but will change it anyway

[stocky]

its probably got something to do with the torque converter locking and unlocking

[Not_An_Abba_Fan]

Look at your leads, one that is on its way out will make the whole car jump when under load.

[ivaninoz]

How many Kilometers has the car?
Have you had any work done on the G/Box?

Have a read just past Half way down, interesting, if true.

TransGo Stage 2 Shift Kitted Valvebody Turbo 700 4l60E - eBay VN, VP, VR, VS, Holden, Car Parts, Cars, Bikes Boats. (end time 10-Oct-07 20:27:46 AEST)

Corrects/Reduces/Prevents - 3/4 clutch and 2nd band burn up
- Slide bump 1st to 2nd shifts
- Reverse to Drive delay bang
- Neutral to Drive delay bang
- Forward Clutch and Low/Reverse Clutch burn up
- Long and soft aggravating shifts

- Converter slip/shudder around 90kms

- Overheating caused by slipping converter.

[Scott98]

the car has done 120k not sure if any work has been done on the g/box but it only does it downshifting from 4th. All other changes seem ok for a commodore (rough for a toyota etc.) It is a bit intermittent and will only do it under load at about 1600 - 1900rpm with light accelerator. If I give it a bit of stick it will change down fine. The engine seems to be running nice and smooth so I think it is definitaley gearbox related.

Thanks for the help
Scott

[ivaninoz]

Like NAAF said,
check your Leads and maybe Coilpack.
If one Sparkplug fails then the other on that Coilpack also fails.

Yes, the symptoms are like it is coming from the Gearbox.

[burnz]

are you getting any codes?
sound's like a fualty t.p.s.

[pumba]

sounds like a typical t700...

my VS does the same thing at abit over 80km/h. and i no plenty of others that do it aswell.

[viper101]

the car has done 120k not sure if any work has been done on the g/box but it only does it downshifting from 4th. All other changes seem ok for a commodore (rough for a toyota etc.) It is a bit intermittent and will only do it under load at about 1600 - 1900rpm with light accelerator. If I give it a bit of stick it will change down fine. The engine seems to be running nice and smooth so I think it is definitaley gearbox related.

Thanks for the help
Scott

Hi Scott

I have exactly the same problem you describe and I've only done 46,000KM, have you resolved the problem yet?

I have been led to believe that this may be a software issue.

Thanks

Viper

[*VOLATILE*]

Look at your leads, one that is on its way out will make the whole car jump when under load.

Had exactly the same problem; replaced my leads (once i had removed the old ones, all the leads were covered in a grey dust; which indicates "arcing" between the leads). Problem solvered.

[viper101]

Had exactly the same problem; replaced my leads (once i had removed the old ones, all the leads were covered in a grey dust; which indicates "arcing" between the leads). Problem solvered.

If it was leads wouldn't it do it under hard acceleration as well or is that not the case ?

Viper

[Not_An_Abba_Fan]

It probably is doing it, but may not be noticeable because the car is accelerating hard. If it is an occasional miss, it would be more noticeable under light acceleration.

[*VOLATILE*]

If it was leads wouldn't it do it under hard acceleration as well or is that not the case ?

Viper

Even from the first gear changes (1-2, 2-3) when I tried to put my foot to the floor, the car would jolt. Heavily. Enough to make me **** my pants twice over. So for about 10 days or so, I was driving like Miss Daisy; even on the freeway. So that is definitely the case

[DND]

My one done the same thing a 80 -100kmh if you were setting on around 80 to 100 and slightly acceleration it felt like it wonted to change gear

After months of trying to find it and taking it to the meks that couldn't find the problem..

Anyway It was dirty injecters and a $10 bottle of injector cleaner fix it...(one bottle of injector cleaner to 1/4 tank or petrol)

I was total pi$$ed off for the $480 bill I got from the meks that didn't fix it and only broke more stuff them they fixed
(thats what happens when you live in retard central)

[viper101]

OK it's definately not the leads I have inspected and tested all leads and coil packs both primary and secondary coils and all are well within specs.

It only ever does it when in top gear and you keep gently accelerating, it's like it want's to kick back and has a few unsucessfull attempts before it does.

We have had it on a scanner and it reported error code 0700 PCM communication error.

I think the injector cleaner will be worth a go I have ony used it once before in the cars life although it only has 46K on the clock, mainly highway driving, it's virtually brand new still.

Viper

[stocky]

i still reckon its something to do with the torque convertor locking up. it will do that around this speed to minimize power loss and increase economy. you gotta put the accelerator down a bit before it unlocks again

[viper101]

i still reckon its something to do with the torque convertor locking up. it will do that around this speed to minimize power loss and increase economy. you gotta put the accelerator down a bit before it unlocks again

I think your on the right track here as it only happens at the speed where it's locked up, on the S/C models it's actually the transmission that tells the engine to reduce torque before shifting, and I don't think that's happening when it's locked up, as you say if you put your foot down no problem it shift's back nicely, but if it's gently increasing acceleration especially up an incline it happens.

[stocky]

well in the first post, it sounds like the first jolt is the TCC unlocking, and then when he puts his foot down more, it kicks back into 3rd

[viper101]

Error I'm getting is P0700 Transmission Control System Malfunction. Any ideas where to start?

[Doctor Bob]

this code doesnt relate to your car VXV6, this is only applicable if there is a Transmission Control Module, try getting a more compatible scan tool connected to it.

as for the trans issue there is a memcal released to change the "lack of power" percieved when accelerating with the tcc locked


Rob

[aokman]

It sounds very familiar to me, it could either be your torque converter dropping in or out or if the car has been tuned it could be too little fuel in lean cruise.

[viper101]

Last service it had the transmission serviced using a non genuine filter and it has only done it since then it could be a co-incidence but I'm going to try a genuine filter kit today and see what happens.

[viper101]

OK filter and oil changed to genuine and problem is still there. I'm going to have to do some road tests and log with a scanner to try and work out what's going on.

[viper101]

this code doesnt relate to your car VXV6, this is only applicable if there is a Transmission Control Module, try getting a more compatible scan tool connected to it.

as for the trans issue there is a memcal released to change the "lack of power" percieved when accelerating with the tcc locked


Rob

Hi Rob,

Where do you get the updated memcal from and any idea how much.

thanks

[Doctor Bob]

Hi Rob,

Where do you get the updated memcal from and any idea how much.

thanks

you need to see what memcal is in it now, post the code & ill look it up