Re: Tata Vista QJD Ownership Review: Brand New Sedan Class (3.4 Years + 85K Kms)
Nice pictures Appu. Whitey looks awesome.
Each glow plug costs Rs. 750 plus labour charges. However my concern is, would there be some other issues related to functioning of engine? By the way, how does glow plug fail?
Don't worry there will not be any issue with functioning of engine.
Glow plug is a heating device used to assist cold start in diesel engines.
Glow plugs reach temperatures in the range of 500 to 600 degrees Celsius in 3 seconds.
Glow plug also assists in controlling emissions in first few minutes and helps to reduce the smoke by efficient fuel burning.
Glow plug require a few seconds to heat up and ready to assist in cranking.
After switching on (only electricals and no cranking) give a few seconds till the coil symbol in red colour vanishes and then only crank to start the engine. This should in general help the glow plug to last long.
Some possible reasons for glow plug failures are:
High voltage reaching the plug (not very common) - could be due to a faulty/loose wiring.
Glow plug not turning off due to some relay failure (not very common) - this again could be due to an electrical fault. (Glow plugs are not designed to be on constantly - with that high temperature they will fail if not turned off after the initial 3 to 4 minutes)
Excess carbon build up in the pre chambers.
Excess spray of diesel in fuel injectors - Glow plug will cool off quickly from such high temperatures due to excess diesel spray (and that is like cooling a heated glass all of a sudden)- the element will burn out.
That is if you accelerate a diesel car like a petrol one immediately after starting, glow plugs could fail. At least during a cold start, Diesel cars should be driven utilizing the torque and choosing the right gears - not plain pumping of fuel right from start. Also avoid pressing the accelerator while cranking/turning on the ignition key - that's not required in a diesel.
(Modern diesel cars are equipped with high pressure fuel injectors that injects fuel into the combustion chamber with precise measurement of quantity and at very high pressure reaching thousands of psi and during cranking this pressure and amount of diesel is very high and therefore pressing accelerator while cranking is not required and an unwanted activity which could cause troubles)
So the most likely causes for failure could be
1. not giving enough time after switch on and the ignition on and
2. Excess diesel injection (like the chamber becoming rich with fuel) as explained above.