I have a '91 import, manual, 300zx TT. It has done close to 60K miles and has developed an odd vibration. The vibration starts dead on 40mph and doesn't get any worse or any better at any speed over this. When the speed drops back below 40mph again, the vibration stops.

 

I have had all the wheels balanced, the prop shaft and drive shafts have been checked and are ok. The gearbox mounts are fine and so are the diff mounts.

 

Does anyone have any ideas on what may be causing this problem ?

This is probably a long shot but try your tie rod bushes, after i changed mine i had a vibration that went away. But it could have been coincedentle.

I hate to say it but, Warren's right.

 

My money's on Tie Arm bushes

 

Tim

Is is the vibration from underneath the centre console or through the steering wheel?

It actually feels like the vibration is coming from the back of the car, you don't get anything through the steering wheel at all.....

Did the people who balance the wheels know what they're doing ? I have known them to cock it up before now.

They have now balanced the wheels twice in three weeks and can't find anything wrong with them. I'm sure they couldn't get it wrong both times ?

I did wonder if this problem was being caused by a dodgy delimeter chip interfering with the hicas or something. I mention this because when I originally test drove the car it was fine (I did give it a good raggin' on the test drive as well!), it was only after I had purchased it that they fitted the delimiter/speedo conversion. The hicas light does come on if you drive the car for some distance, and the 'lights' light comes on if you switch the lights on or brake, is this normal ? Or am I shooting in the dark with this ?

well the hicas light is definatly in that case your steering wheel put back on scew. This effects the alignment of the hicas and like you say after driving a little while on a motor way or something the light comes on indicating that the hicas thinks your wheels are not tracking straight. so the system disengages itself.

i still say check your tie end bars

This could be HICAS related, diff, drive shafts, rotors, wheels etc.

 

Sometimes garages ommit the obvious - Yes, they could be balanced properly but are they actually round? Are they buckled?

 

I would ideally need to be in the car to experience the vibration, however I think the clue you gave about the speedo conversion is the place to start looking. Remove the conversion and see if it resolves the problem. Do you know what type of conversion has been fitted?

 

Andy

The steering wheel is actually out by about 25 degrees clockwise, I'll get this sorted as soon as I can get a 2 inch puller to remove the wheel.

 

I'll check the tie rod bushes once I have picked the car up and got it back home tomorrow. The garage currently has it trying to find/cure the vibration, but as of 4pm today, they can't find anything that would cause it ??????

 

Is there anything I should be aware of/look for with the tie rod bushes other than general wear and tear ? If they are worn is there and uprated replacemt part available, or is the standard part ok ?

I have no idea what type of conversion was fitted, or where to start looking for it ? They did mention something about fitting a chip in the back of the dash panel behind the clocks. Does this make any sense to you ?

Why the puller to remove steering wheel?...On mine just large nut take off and then just rock the wheel side to side "usually" comes off easy...

 

Make sure Hicas sensor is position bang on 12 O clock..

 

Regardz

I have tried the 'gentle' (and brute force) method of removing the wheel, but no joy..... Hence the puller.....

Just a stab in the dark here but how are your rear shox??? Could be that you have a worn shock which is allowing the wheel to bounce which in turn is causing the funny vibration feeling....

 

You shouldn't need a puller to get the wheel on though Rock from side to side while pulling it and it should jump off.... Give it a good tug but watch it doesn't implant itself in your chest when it does go

 

CheerZ,

 

Andy

was your prop taken off and checked i had the same symptoms i tried turning the prop round no good when i took it off it seemed fine to me i took it to a specialist and the centre bearing was shot and the front uj was nothcy i had a one piece made solved problem

hope this helps

mark

Guys, do any of you know of a good garage to diagnose and fix transmissions in the South?

 

I'm J8/9 on the M4 so there or there abouts would be ideal. If further afield then no problem.

 

All i want is to leave it with someone fix the bugger and give it back to me.

 

Simon

 

[This message has been edited by Simon (edited 08-01-2002).]

On wheel balancing, having had it done twice is no guarantee. I had balancing done twice by a place with a good reputation locally. Then got fed up and took the car to main dealer who used a different place which solved it.

 

Having said that, you should be able to 'drive out' of a balance induced wobble so if it starts at 40 mph but doesn't disappear at higher speeds then my money would also be on tie rods.

 

Dave