Vibration when accelerating

[89berlina]

Hey guys,

Here is the issue. I have a 89 VN berlina wagon and at the moment there is a bad vibration in it when you accelerate. When you floor it though the virbation goes away. It occurs mostly between 60 - 80km/h when you're accelerating lightly to keep speed if you know what I mean. Its like a shuddering type vibration, like something is unbalanced. Idle is also abit rough at the moment too. Here is what Ive replaced/fixed that shouldnt be the problem.

• IAC valve
• Fuel tank flushed and cleaned as well as the fuel filter replaced (was filthy)
• New leads, spark plugs (excellent spark)

This is becoming really frustrating and any help would really be appreciated. Thanks in advance

Rhyan

[accentstencil]

Check the engine mounts.

[88GreenVN]

Uni joints or centre bearing???

[Pub247]

+1 for greenvn. If it does it when you take off quick from a standing start then its more than likely the things mentioned above

[greenfoam]

If it's a vibrating light load in 3rd gear from about 80-120 it's the gearbox mount. They don't seem to break in the V6 like they do in the 5 litres tho, most 5 litres tend to have a busted one and vibrate to the crap but no one seems to knnow the 5 litres should run limo smooth not vibrate your teeth out like the V6 does. It's something worth looking at though as this was my mystery vibration and it's been the cause of quite a few other peoples too

[89berlina]

Engine mounts have been replaced because I had to change them for roadworthy and its more like what greenfoam said. Its also had a second hand gearbox installed and the transmission mount looked really good - no cracks or anything. There's no vibration when you accelerate hard off the mark either. Only when accelerating lightly at higher speeds at around 60 - 80km/h. Recently I cleaned the fuel tank out and it was absolutely filthy so not sure if its still working junk through the system that may be causing the vibrations. After driving today the vibration seems to have gone away. It seems to happen most when the car is cold in the mornings. Will see how it goes tomorrow morning. Appreciate the advice so far

[hjtrbo]

Sorry to hi jack the thread but while we are on the topic I thought I could sneak in my question???
VP 5L I have also have a vibration, at around 2000rpm it is at its worst. It also does it when just sitting parked in the driveway, if I rev it up and sit it on 2G rpm its like the car hits resonance. Balancer or mounts???

[LightningVP]

Just curious, but when it's vibrating, if you change into another gear and keep your foot in same spot does it still do it?

[88GreenVN]

Just curious, but when it's vibrating, if you change into another gear and keep your foot in same spot does it still do it?

Good point - Touque converters can viabrate when going into lockup at around 80.

When my converter went in the wagon I also had squeels and grinding.

[LightningVP]

Good point - Touque converters can viabrate when going into lockup at around 80.

When my converter went in the wagon I also had squeels and grinding.

mine does what his says and have had many different opinions from alot of different people, and if his does what I asked then most likly the same problem...

[89berlina]

Certianly hope its not cause Ive removed and installed that gearbox 3 times now You've brought up a good point though. The car vibrates when the car is just about to kickdown. Ive tested this and it seems to occur at this point. The thing is though, when the car is warmed up there is no vibration. Is this showing the right symptoms relating to the torque converter? I have a spare anyway so thats not a problem, its just a big job having to change it

[89berlina]

I just took the car out for a run and noticed the fuel pump wasnt whining anymore but buzzing as usual. The car drove normally and there absolutely no vibrations. Could this be the issue???

Thanks guys,
Rhyan

[LightningVP]

"noticed the fuel pump wasnt whining anymore but buzzing as usual."

What do you mean by that?

[Glen_P]

I've got the same passenger side vibratiion, it's actually very loud. Happens as soon as it hits 60kph and i'm slowly accelerating up till about 90kph then goes away.

I'll probably give it a good inspection over the weekend and see what I can find

[LightningVP]

looks like a common problem :S

[89berlina]

I've got the same passenger side vibratiion, it's actually very loud. Happens as soon as it hits 60kph and i'm slowly accelerating up till about 90kph then goes away.

I'll probably give it a good inspection over the weekend and see what I can find

Yeah that'd be good Keep us updated. Would help me figure out what is wrong with mine.

Lightning Vp - I meant you usually hear the pump buzzing quietly as normal if you're near the rear of the car, where as mine was making a obvious whine which was quite loud and sounded as if the pump was struggling and could be heard inside the car. Its definietly not normal.

I was thinking that it may be the centre bearing or uni joint on the driveshaft as mentioned by 88greenvn but Im pretty sure it would be a constant vibration if that were the issue