Engine jerks in Maruthi suzuki Baleno

I have a 2000 Model Maruthi Baleno which has clocked nearly 1 Lakh Kms. Recently the car has started to jerk at times, especially at RPMs below 2000. After much consultation, the mechanic diagonised it as a cord wire failure and changed one of them. For a few days all was well but the jerking started appearing again. However it does not happen on all days. Please suggest remedies.

Post edited to remove bold format (for better readability).

Well, this could involve many things to check...

• Fuel pump
• Fuel filter
• Fuel lines
• Spark plugs
• Injectors
• Distributor
• Valves/tappets
• Timing belt
• Air filter

S = k.I^2, where S is the amount of stupidity a species possesses, I is the intelligence the species has and k is the universal constant of stupidity.

Thanks for the suggestions. I have tried out changing the spark plugs. Fuel tank has also been cleaned. Ignition coil has been changed. Remaining possibilities shall check in due course. The mechanic just could not spot the exact fault. I wonder if this problem has been experienced by any other Baleno users. Hopefully the exact problem could be nailed instead of going in for trial & error methods? Meanwhile the jerking still continues.

i think it should be the fuel pump. Try checking that!

Why break rules when following them is much easier!!!

yes even i too getting same problem after changing clutch plates nd gear box oil...it jerks,rattels what all...sometimes it vanishes nd comes back...mech did some thing which led to this...even mine is 2000 baleno...looks  like time to scrap car nd make it show piece 

The problem seems to be solved after changing both cord wires. However there appears an occassional hiccup & the engine fault light comes on at this time & if in low rpm the engine switches off. But on restarting & revving the engine it picks up & the engine fault light switches off & things become smooth. On checking up with a dealer they have diagonised it as cam shaft sensor fault. Have been advised to replace the same. Costs around Rs.2500/- I believe. But wheter this is the actual fault?

Hard to say without actually looking. Before replacing any sensor, check the accelerator cable play/tension - it may have become too loose. Next to check is the TPS (throttle position sensor) - it will be located coaxially with the throttle's spindle (the semi-round thing to which the accelerator cable finally connects). If this is faulty you will have idling problems, plus the occational engine "suck-out" - sudden jerking or loss of power which goes away when you accelerate a bit more. You might also notice that the car responds to acceleration in a "delayed" sort of way - at first nothing seems to happen, and then suddenly there is a surge in power - a classic sign that the TPS is bad. Thankfully, this is a very easy to replace part and most easily recognised. TPS fault may also turn on the check engine light - but may also reset it if for some range the acceleration is normal.

Next to check is the IAC - ask mechanic where this is and get it checked. If this is jammed/faulty then you will get rough idle. Next sensor is the MAP/MAF - fault in these will turn on the check engine light. Lastly to check is the O2 sensor. However, if you proceed step-by-step above, you will locate the source of the problem.

CAM sensor - what is this? I guess they're referring to the cam position sensor - this gives the a readout of the engine's RPM and also used for injector timing. Fault in this will not cause intermittent problems, so this is probably the last thing to look at - after all else has been checked and found to be fine and still problem exists.

S = k.I^2, where S is the amount of stupidity a species possesses, I is the intelligence the species has and k is the universal constant of stupidity.

how did the dealer diagnose that the cam sensor is bad? Did they use a scanner which plugged to the ecu will give details about the fault (especially about sensors and electric connections) and hence you get the exact picture for the solution.

Hi, I believe the dealer has scanned the ECU with the help of a machine. At least thats what they told me. The problem I have mentioned now is not constant. On certain days the vehicle runs very smooth without any problem even after travelling 30 to 40 kms.