Ignition Coils Burning Frequently

[Crosswind]

Good day folks!

Having some trouble with the Cerato after few years of use and abuse. Need some ideas to troubleshoot.

1. Ignition coils keep burning. This car has 'bottle type' coils that can be replaced individually and they keep burning frequently (one by one). I think I've replaced like 6 or 7 (altogether) in the past 6 months.

2. Water level in the radiator goes down mysteriously and the engine starts heating up. Repaired the radiator but it prevails. No visible water leaks when the car is parked and it gets pressurized. Mechanic suspects the head gasket is gone. But I dont see no oil in water or white exhaust.

3. Brakes seem to be having a vacuum leak ('brake gal wenava' as they say in local lingo), which didnt go away even after replacing vacuum lines (note that i havent replaced the brake booster... not yet).

Could these be interconnected? Any ideas (even long shots) to help troubleshoot?

 

[Davy]

The Cerato has a bottle type ignition coil? I find that hard to believe. Pretty sure it has a regular "coil over plug" set up where each coil powers either 1 or 2 cylinders. I'm gonna assume this is the case and base my response on this assumption.

1. The coils are supplied power through the ECU by determining many engine parameters including the crank position sensor. If the ECU supplies more power than the rating of the coil, it will eventually burn out. So it could be that your replacement coils are simply wrong (were they used?) or your ECU might be at fault. Just my 2 cents.

Having said that, first you need to make sure that none of your engine's ground connections are bad. Especially the ground connection from the battery and the one(s) connecting the engine to the car's chassis. Also, make sure you get the alternator and charging system checked to make sure that the battery is not being overcharged. 

 

2. Might be a very small leak where the coolant evaporates before it even hits the ground. Hope you thoroughly inspected the engine compartment (water lines) for coolant trails or smudge marks. The bright colour of the coolant should allow you to spot it fairly easily. The leak might be in the AC heater element as well. 

Didn't you have a brake issue with the Cerato a couple of months back?

 

3. You can do a simple test to determine if the booster is operational:

Hope this helps.

[Crosswind]

@Davy- Yes its coil over plugs. For some funny reason, mechanics nowadays seem to call them bottle-type. Obviously its not the 1970's type coil i'm taking about. The coils are brand new and genuine Mobis (official supplier for Hyundai and Kia) ones. I normally don't use non-genuine parts with my cars. I got Saman from Kalubowila  to go thru the electrical system of the car with a fine-toothed comb some time ago. He couldn't find any fault. But you are right, I too suspected the ECU. On the other hand, is there any remote possibility that this may be related to head gasket? That's what I'm trying to figure out - whether the mechanic is talking bull.

I thought the brake problem went away but its still there.

[Dushyantha]

  On 8/16/2016 at 2:02 AM, Crosswind said:

2. Water level in the radiator goes down mysteriously and the engine starts heating up. Repaired the radiator but it prevails. No visible water leaks when the car is parked and it gets pressurized. Mechanic suspects the head gasket is gone. But I dont see no oil in water or white exhaust.

 

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Had this same problem once in a car where the car started heating up but there wasnt any oil in water or water in oil. and just like you i went and cleaned out the radiator and checked the whole cooling system .in the end it turned out to be a teeny weeny leak in the gasket . being a cheapskate i just replaced the gasket which solved the problem but i t came again after some time . in the end took the whole engine out faced the head . cleaned out all the coolant lines in the engine and fixed up everything with a new gasket and this solved the overheating and radiator pressurizing problem for me so urs might also be something like that .   hope it helps 

[LancerL]

If you don't have outside visibility of coolant leaks, then it should be the head gasket leaking coolant in to combustion chamber where it turns out to be steam and goes out from tail pipe.

First takeoff radiator cap and let the car to run until operating temperature and see you get air bubbles out (Rev a bit about 3000RPM).  If you don't get any bubbles and only coolant overflowing then there will be no leaks on to combustion chamber.

The next you could do is take the dipstick out (better to collect and inspect drained out oil from sump) and see if you get any white mix on it (When water mixed with oil it get whitish).

Please post your observations.

 

 

 

[terrabytetango]

Could also be a leaky radiator cap, which leaks just enough to let some water vapour out. Does it lose water while sitting in the garage as well? 

[Davy]

  On 8/16/2016 at 4:50 AM, Crosswind said:

@Davy- Yes its coil over plugs. For some funny reason, mechanics nowadays seem to call them bottle-type. Obviously its not the 1970's type coil i'm taking about. The coils are brand new and genuine Mobis (official supplier for Hyundai and Kia) ones. I normally don't use non-genuine parts with my cars. I got Saman from Kalubowila  to go thru the electrical system of the car with a fine-toothed comb some time ago. He couldn't find any fault. But you are right, I too suspected the ECU. On the other hand, is there any remote possibility that this may be related to head gasket? That's what I'm trying to figure out - whether the mechanic is talking bull.

I thought the brake problem went away but its still there.

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Oh right. I was a bit confused about the ignition coils for a minute there. If there is a gasket leak, there is a very slim chance for coolant residue to be deposited over the spark plug electrode that in turn cause their resistance to become higher and thereby causing the corresponding coil to overwork, heat-up and fail prematurely. This again is thinking out loud while being a bit paranoid.  But anyway, have you checked your spark plugs? Did you change them and maybe the new ones are of higher resistance?

I think you have a few things to check now for issue #1:

- Ground connections

- Alternator and charging (idle, load etc.)

- Condition of spark plugs (this might give you an indication of a gasket leak, but not if the leak is very small)

As for the coolant level drop, check the heater element inside the car and the lines + what others have suggested above. If it's a gasket leak, there's no way to find out without taking the valve body out. I have one of these to diagnose issues without taking stuff apart. Can take the 4 plugs out and insert the camera through the plug hole and look around for trails of coolant + corrosion.  I wonder if any local garage has a industrial version of this type of "endoscope".