[lordofgondor]

Hey Folks, facing a delima with an Alto, big time!

The problem is that at each gear, a weird thak-thak kinda sound comes from the engine only at a particular speed for that gear, but not on other speeds. In second gear, it's at ~20 Km/hr, third gear it's ~40 Km/hr, 4th it's ~50 Km/hr. In any of the gears, if the speed is below/above the ones mentioned, there's no sound. Furthermore, there's no knocking or jerks while driving, just the sound.

I'd be grateful for any light being shed on this nagging issue.

EDIT: The car's been run for ~35K Km, and was serviced coupla weeks back. That's when the sound issue crept in.

[libranof1987]

Originally Posted by lordofgondor

Hey Folks, facing a delima with an Alto, big time!

The problem is that at each gear, a weird thak-thak kinda sound comes from the engine only at a particular speed for that gear, but not on other speeds. In second gear, it's at ~20 Km/hr, third gear it's ~40 Km/hr, 4th it's ~50 Km/hr. In any of the gears, if the speed is below/above the ones mentioned, there's no sound. Furthermore, there's no knocking or jerks while driving, just the sound.

I'd be grateful for any light being shed on this nagging issue.

EDIT: The car's been run for ~35K Km, and was serviced coupla weeks back. That's when the sound issue crept in.

What engine rpm do you generally change the gears at? Something between 2.5-3 krpm is ideal..

Is this sound with or w/o A/c?

At 35k, was the air n fuel filter changed? Probably, you could get that re-checked.

[lordofgondor]

I've been up shifting in my Esteem & Estilo between the 1.5 - 2 K RPM mark and have never faced any issue. Shifting at low RPM can cause knocking, but that's not the problem being faced with the Alto.

The sounds coming with A/C off, haven't checked with it being on.

The fuel filter had been changed at 30K service & the air filter was changed at this service.

What's really confusing me is the fact that the sound is coming only at particular speed w.r.t each gear!!!

[libranof1987]

Originally Posted by lordofgondor

I've been up shifting in my Esteem & Estilo between the 1.5 - 2 K RPM mark and have never faced any issue. Shifting at low RPM can cause knocking, but that's not the problem being faced with the Alto.

The sounds coming with A/C off, haven't checked with it being on.

The fuel filter had been changed at 30K service & the air filter was changed at this service.

What's really confusing me is the fact that the sound is coming only at particular speed w.r.t each gear!!!

I think sound at particular speed w.r.t each gear essentially means something related to the engine rpm..

Since the car has been serviced just 2 weeks back, you could go back to the service stn and ask them to have a look..

Just to eliminate some causes, how about changing gears betn 2.5 to 3k rpm n then checking if the problem persists.

[lordofgondor]

Originally Posted by libranof1987

Just to eliminate some causes, how about changing gears betn 2.5 to 3k rpm n then checking if the problem persists.

Will give it a shot mate!

[lordofgondor]

Just got the problem fixed.

The issue was with the gear bearings, which essentially were shod. 5 bearings were replaced and the sounds have vanished and the car feels even smoother to drive.