[Kosfactor]

Originally Posted by IP_Man

IMP update: When fuel tank is full, vibration intensity reduces to the minimum. Could this is because of damping due to fuel weight? As fuel tank becomes empty vibration intensity increases. Or, is it something to do with fuel pressure?

So the engine is not getting enough fuel as it starts to rev up.

This used to happen in some old M800s, when the fuel tank is near empty - low fuel pressure.

I hope it's just the filter or lift pump.

[pareekvirendra]

I am not sure if this helps, but i have had this exact same issue in my Corolla Altis diesel. For me, it happens when my car crosses 2000 rpm i.e. between 1900 and 2100 rpm. There are no vibrations before or after this rpm. I believe my engine had a turbo lag upto 2000 rpm. I had parked my car at Toyota ASS for a few days and they did a lot of things, including cleaning out the EGR valve. They even checked the engine mounts, which were fine. Finally they couldn't solve it, and since I needed the car back I told them to let it rest for the time being.

The problem still exists for me and it is more noticeable at higher gears i.e. 4, 5 and 6.

I am not really sure, but I believe it has something to do with the turbo lag. At 2000 rpm the turbo kicks in and it does something that causes these vibrations, however, when it is done kicking in or starting, or whatever it does, the vibration goes away.

I don't think this is an issue limited to just Tata, and is found across all turbo engine cars. Though how to solve it is quite beyond me.

[amit_purohit20]

Originally Posted by pareekvirendra

I am not sure if this helps, but i have had this exact same issue in my Corolla Altis diesel. For me, it happens when my car crosses 2000 rpm i.e. between 1900 and 2100 rpm. There are no vibrations before or after this rpm. I believe my engine had a turbo lag upto 2000 rpm

Maruti Swift Diesel cars also suffer from the same problem. I have the same problem in my car where the gear lever vibrates in 1700 to 2000 rpm, after which the turbo spools up and provides sufficient torque thus reducing the vibration.

My research and anlaysis on this topic is that its the torsional vibration issue which affects the driveline.
Being just 4 cylinder and less cubic capacity engines these engines cannot provide sufficient torque at low rpms in higher gears where torque demand is more. This causes torsional vibrations and leads to Body Boom or Gear lever vibration like in my car.
Solution is to attack on rotating components which can damp the vibration and also isolate components which vibrate -
1) Replace the clutch. Clutch has torsional springs to reduce torsional vibrations. May Swift owners have replaced the clutch and found the solution to this vibration but only limited to 40k-50k kms after which it again starts vibrating. Reason- The torsional springs get weak and don't give the necessary damping hence a clutch which has not reached its end of life has to be replaced. I did this on my csr and found 50 percent improvement.

Tip- Never buy a clutch which has its torsional damping springs loosely mounted. Always inspect the new clutch assembly by shaking it and if you find the torsional springs making noise due their movement, discard the particular assembly.

2) Replace the plastic bushes and add stiff rubber near the cable shift mounting just near the bottom of the gear shift lever assembly.

3) Most important but most neglected - Replace the Torsional damper pulley mounted on the crankshaft.

@Thread starter please note the last point, a cheap and efficient way to reduce torsional vibrations. If your vehicle vibrates more while driving than idling its a case of torsional vibrations. But first check for all loose dangling pipes and covers.

[IP_Man]

Originally Posted by superguy282

It could very well be the fuel pump.

Could be. But fuel pump suck diesel, very little is used by engine, remain diesel again go back to the tank. So diesel is in continuous circulation, how low level in the tank affect performance, I don't know? Because fuel is not gravity fed to the engine.

Originally Posted by Turbanator

Try with one or two sand bags in the trunk. Also, check if it stays or goes when there are passengers in the rear seat!

Why sand bags? This is seven seater car. On many occasions, there were seven people (two at the back) in the car but vibrations are still there.

IMO, vibration transfer route: Engine => engine mounts => Ladder frame => Rubber bushing => Passenger cabin. Fuel tank is mounted on the ladder frame. So full fuel tank may be damping vibrations on the ladder frame, hence little is transferred to passenger cabin. This is just my thinking real reason I don't know.

Originally Posted by SS-Traveller

No, did they change the rubber body mounts before re-torquing?

Good point. I will check that.

Originally Posted by landcruiser123

I meant Body mounts. These hold the body to the chassis in a body-on-frame SUVs.

Good point. I will check that.

Originally Posted by amit_purohit20

My research and anlaysis on this topic is that its the torsional vibration issue which affects the driveline.

Yes. That is the reason they use 'Duel Mass Flywheel' (DMF) to dampen the torsional vibrations but Safari uses single flywheel and and torsional vibration damper (TVD) coupler on the drive shaft. DMF does far superior job than TVD.

[alpha1]

Now that you have raised the point, I see that all the vehicles that I own / driven: two wheelers, four wheelers, seem to have their resonant peak around 1000-1500 RPM.
ALL

Idling is typically below 1000 RPM, so the shaking is less, however with extremely fine throttle response we can reach around 1100-1200 and I observe that most vehicles do shake their max around this point. Post this - not much vibrations.

And the effect is more pronounced in old vehicles.

[srini1785]

Originally Posted by IP_Man

IMP update: When fuel tank is full, vibration intensity reduces to the minimum. Could this is because of damping due to fuel weight? As fuel tank becomes empty vibration intensity increases. Or, is it something to do with fuel pressure?

I will tell you one incident that happened in my line of work. A power plant tripped twice in a span of 2 days. For those who might not know, power plants have some really complex vibration monitoring systems for the turbine + generator combo which trips the plant in case the vibrations exceed a certain value. Plant tripping is a major incident. When one plant ( feeder ) goes off the grid means no power to certain areas of the city and all phones start ringing.

After repeated attempts to find the root cause, when the maintenance team ( obviously under too much pressure ) , they found out that during routine maintenance , one operator had missed a spacer washer for one mounting nut. This washer was machined for 5 Micron fit and when tightened with proper torque settings, the vibrations stopped and all was ok.

Its difficult to find the exact reason for vibrations. I would suggest you look at the fuel tank. Sorry can't help you further.

[Kosfactor]

Originally Posted by IP_Man

Could be. But fuel pump suck diesel, very little is used by engine, remain diesel again go back to the tank. So diesel is in continuous circulation, how low level in the tank affect performance, I don't know? Because fuel is not gravity fed to the engine.
--------
Yes. That is the reason they use 'Duel Mass Flywheel' (DMF) to dampen the torsional vibrations but Safari uses single flywheel and and torsional vibration damper (TVD) coupler on the drive shaft. DMF does far superior job than TVD.

I assume the vibrations were from the front of the vehicle and not the rear. If the lift pump is vibrating, you will hear it before the engine starts. If the lift pump or a clogged filter is not supplying enough fuel afterwards once the engine starts to run, the vibrations would be from the engine side itself.

If this vehicle was frequently run in 'reserve' condition, lift pump would be a good place to look.

Dual Mass Flywheel is smooth no doubt, it also is bloody expensive to replace - and it must be replaced along with the clutch, normal flywheel replacement is optional.

[rkw]

Originally Posted by pkulkarni.2106

You've said that the vibration intensity peaks at 1000 RPM & it's ~26 Hz at that time.

A simple Hertz to RPM calculation shows this frequency to be 26 x 60 = 1560 RPM.
Could there be any other component which is running at 1560 RPM when engine is at 1000 RPM? e.g. a Power steering pump or the AC compressor?

I believe this will hold true only if referring to vibration from rotating parts. But in this case the vibration can also be either linear or oscillatory.

[Rahul Bhalgat]

Originally Posted by rkw

I believe this will hold true only if referring to vibration from rotating parts. But in this case the vibration can also be either linear or oscillatory.

Yes, but which car part undergoes a linear / oscillatory motion without driving (or being driven by) a rotational motion?

[IP_Man]

Originally Posted by alpha1

Now that you have raised the point, I see that all the vehicles that I own / driven: two wheelers, four wheelers, seem to have their resonant peak around 1000-1500 RPM.
ALL

I did small research. I test drove many diesel of the same/different capacity for e.g. Crysta, Creta and Tata Safari Storme VX (Varicor-400), I did not find any vibrations in that said particular RPM band that will trouble me. I don't mind small vibrations. In my friends car, they are bothersome definitely.

Originally Posted by Kosfactor

I assume the vibrations were from the front of the vehicle and not the rear. If the lift pump is vibrating, you will hear it before the engine starts.

I don't hear anything when key is turned ON. May be fuel pump is cam driven and not electrical. Also I don't think any individual vibrating component can shake entire car. These vibration are definitely originating from the engine.

Originally Posted by rkw

I believe this will hold true only if referring to vibration from rotating parts. But in this case the vibration can also be either linear or oscillatory.

Any rotating component can have vibrations if not balanced properly. That is why we balance our tyre in wheel alignment.

When car is in neutral and by giving fine throttle, if I bring engine RPM in-between to 1000 and 1100 RPM, I do feel vibration intensity peaks but very slight. It gets amplified and bothersome when engine is put on the load.

[a4anurag]

Originally Posted by IP_Man

When car is in neutral and by giving fine throttle, if I bring engine RPM in-between to 1000 and 1100 RPM, I do feel vibration intensity peaks but very slight. It gets amplified and bothersome when engine is put on the load.

Get the engine + transmission mounts checked. If required, loosen all the mounts, tighten them again as per the required torque values specified by the manufacturer.

[khan_sultan]

I used to have a Prado where I had similar issue. See the discussion here (1998 Toyota 90 Series SWB 3 Door Land Cruiser Prado. EDIT: Now with 2" Ironman Lift)

Quoting for reference from that thread:

#1: I see a 'boom' noise (kind of resonance noise) in all gears at greater than ~2K RPM and upto 3K RPM. Below that it does not exist and above 3K RPM it reduces a LOT. At those RPM, if I put in neutral or depress the clutch, the boom noise vanishes.
Previously, when there was leak in silencer, this boom noise was much much more pronounced. Now with the silencer gaskets replaced, it is a lot less but still there.

Need to find out why/where it is coming from and how to remove it. Is it from silencer, or transmission or maybe that dynamic balancer. (I can see that the dynamic balancer rubber has cracked with age )

I was able to narrow it down to a dynamic balancer. Read the discussion on this topic here (1998 Toyota 90 Series SWB 3 Door Land Cruiser Prado. EDIT: Now with 2" Ironman Lift)

Hope this helps in some way to narrow down where the issue is.

[rkw]

Originally Posted by Rahul Bhalgat

Yes, but which car part undergoes a linear / oscillatory motion without driving (or being driven by) a rotational motion?

Right, so my presumption is that engine idling at 1000 rpm itself can lead to a linear or oscillatory vibration of 26 Hz without necessarily going through another rotary moving part of 1500 rpm.

[varun560061]

As per above comments and updates I could note that Vibration is in a particular rpm range. And this is a refresh Storme (post 2016) , since I own the same model and version I can relate to this issue.. There is a similar vibration in my car.

But I have got the source of few over the time.

1 - The Intercooler metal pipe has a metal supporting from exhaust manifold
which is missing (broken due to rust, common issue with Hexa and Storme). Weld a support

2 - Check the compressor clutch bearing

3 - Check the AC condenser fan, in mine there was an imbalance in the fins and used make a rhythmic vibrations felt.

PS - Can you let me know where is the car (city)..

[IP_Man]

To diagnose and rectify driveline vibration a drive shaft is balanced by adding weights.

https://youtu.be/zuPSGJZpL3k