Knocking Sound in Santro

[Jaggu]

Originally Posted by alv

Need your help - My zen for the last 1 year has this peculiar knocking sound ( its like a wooden knocking ) sound that comes from the drivers side fron from below the bonnet . Its a Thud - thud sound and its very very irritating . I have visited 3 different Maruti service centres with this problem NO ONE has found a solution - Now heres what happens

This sound is heard ONLY during summers ( afternoons , heavy traffic in evening sessions ) , no sound at all through winters , rainy season only during summers . This happens after i have driven about 8 Kms + and the engine is sufficiently hot , once the engine cools there is no sound and begins once again after reaching a particular temp .

I know its something to do with expansion of some part on heating - but neither me ( given my limited technical knowledge on cars ) nor the service guys ( shame - given their experience in this field ) are able to sort out the issue .

anyone who has faced a similar issue -pls respond so that i can pin point the problem to service guys and get rid of it.

Have you checked engine mounts?

[alv]

Thanks Jaggu - will have the engine mounts checked at the next service . Hope this is not an expensive service job as i plan to sell off the car soon .

[anooppb]

Hi Team-BHP

This is my first post in this forum

I have a 2004 model Santro Xing. The car has clocked around 35,000 Km.
I had used only Xtra premium petrol from the day i purchased the car

Around one month back the car engine started knocking. The service engineers couldn't find any issues with the engine, but they accepted that engine is knocking after the car reaches around 60Km/hr. They suggested that the problem could be because of the premium petrol I am using and asked me to change it to normal petrol.

I am using normal petrol from then onwards, but the issue is still there.

I have heard that usage of normal petrol could lead to knocking in the long run, but this is the first time I am hearing usage of premium petrol could lead to knocking.

Can any of you guys advise me on this? Has any one faced similar issues?

[vaasu]

Originally Posted by anooppb

Hi Team-BHP

This is my first post in this forum

I have a 2004 model Santro Xing. The car has clocked around 35,000 Km.
I had used only Xtra premium petrol from the day i purchased the car

Around one month back the car engine started knocking. The service engineers couldn't find any issues with the engine, but they accepted that engine is knocking after the car reaches around 60Km/hr. They suggested that the problem could be because of the premium petrol I am using and asked me to change it to normal petrol.

I am using normal petrol from then onwards, but the issue is still there.

I have heard that usage of normal petrol could lead to knocking in the long run, but this is the first time I am hearing usage of premium petrol could lead to knocking.

Can any of you guys advise me on this? Has any one faced similar issues?

I too had experienced similar issue in my 2004 model Santro Xing.

I had used BP Speed right from the day one and couple of months back the pinging noise under the bonnet started. I could also feel the drop in power. The service station too gave the same explanation that it is caused by premium petrol. But, I reasoned that it should be a problem with other Santro's as well. My friend too have a 2004 model Santro Xing and he never faced this issue although he only fills up with BP Speed from the same gas bunk.

Service station guys even cleaned up the petrol tank and filled up petrol from the gas bunk they visited regularly, but still the problem persisted.

Resetting the ECM did not help either.

I insisted that it appeared to be a problem with the ignition timings and they swap ECM from another Santro to rule out the problem with ECM. On swapping the ECM from the donor car the pinging problem did not reoccurred and pickup appeared normal. However, on plugging back my ECM the problem did not resurface either! The service guy could not explain this behaviour.

The pinging problem resurfaced after a couple of weeks. This time I switched to normal petrol and have not experienced pinging problem since then.

Couple of my friends had a similar problems with their cars - 1999 carb Maruti 800, 2004 WagonR when they switched to BP Speed. Reverting back to normal petrol solved the problem for them.

However, I still do not have an answer why it works fine in my friend's 2004 model Santro Xing?