Head gasket? 1.2 Corsa C
Discussion
Hi,
I've got a 54 plate Corsa C with just under 120,000 miles - recently I've noticed that it's been leaking coolant at a fairly swift rate, although there's no visible leaks. There's a bit of mayo under the oil filler cap, but nothing more than normal. The oil on the dipstick is fine, and the engine runs smoothly.
I took it to the normal garage, which while good, had at least a 2 week wait to even look at the car. The mechanic said that it sounded like the timing chain cover gasket had failed, which was is a common issue on the car, but worst case could be the head gasket. If this was the case, it would be uneconomic to repair.
I then tried a second garage, who pressure tested the coolant system and found it was fine. Based on this, they said it was probably the head gasket.
Two questions -
1) Would the pressure test definitely rule out the timing chain cover gasket?
2) Is there anything else it might be?
Thanks in advance for any advice.
I've got a 54 plate Corsa C with just under 120,000 miles - recently I've noticed that it's been leaking coolant at a fairly swift rate, although there's no visible leaks. There's a bit of mayo under the oil filler cap, but nothing more than normal. The oil on the dipstick is fine, and the engine runs smoothly.
I took it to the normal garage, which while good, had at least a 2 week wait to even look at the car. The mechanic said that it sounded like the timing chain cover gasket had failed, which was is a common issue on the car, but worst case could be the head gasket. If this was the case, it would be uneconomic to repair.
I then tried a second garage, who pressure tested the coolant system and found it was fine. Based on this, they said it was probably the head gasket.
Two questions -
1) Would the pressure test definitely rule out the timing chain cover gasket?
2) Is there anything else it might be?
Thanks in advance for any advice.
lemonoo7 said:
It could be the heater matrix leaking, it happened to mine. However I would have thought the carpets would have been wet and slippery.
The carpets are bone dry unfortunately.Mr2Mike said:
Could also be the coolant pump, a hose or the radiator. Small coolant leaks that only occur with a hot engine can be very difficult to spot sometimes.
The coolant pump was actually replaced about 6 months ago, so I'd hope that wasn't the cause. You're right about it being hard to spot if it's not going into the engine!GreenV8S said:
A block tester would let you confirm or rule out the head gasket theory.
That's an idea, thanks.It's a long shot, but I've ordered a replacement cap for the coolant header tank to see if that's got anything to do with it. I'd like to think that if it was the head gasket, it'd be fairly obvious by the time it was losing this much coolant.
You can buy stuff to test for combustion gasses in the coolant.
See: https://www.ebay.co.uk/p/Bt-1-2x50ml-Combustion-Le...
JOhn
See: https://www.ebay.co.uk/p/Bt-1-2x50ml-Combustion-Le...
JOhn
I helped a fried doing a HG change on a Corsa 1.4i. Horrible to remove and reinstall the gazillion pipes, hoses and various injector parts.
That engine bay was designed for single point injection at most and then they added MPi, EGR etc. to it over the years. Everything is so crammed that you have to stick to a particular order in fitting the various pies etc. to be able to mount them all.
Once you work on the car, you'll understand what I mean.
The mechanical part, timing belt access etc. is actually well designed and easy to do.
Do only use OEM valve cover gaskets. The cheap after marktet s...t is dimensionally wrong and does not sufficiently protrude the cover to seal properly. We recycled the old gasket rubber and it seals 100% even after all this time.
That engine bay was designed for single point injection at most and then they added MPi, EGR etc. to it over the years. Everything is so crammed that you have to stick to a particular order in fitting the various pies etc. to be able to mount them all.
Once you work on the car, you'll understand what I mean.
The mechanical part, timing belt access etc. is actually well designed and easy to do.
Do only use OEM valve cover gaskets. The cheap after marktet s...t is dimensionally wrong and does not sufficiently protrude the cover to seal properly. We recycled the old gasket rubber and it seals 100% even after all this time.
Sorry to bump this thread but thought I'd post an update (and a follow-up question!)
I changed the coolant tank cap and the loss of coolant slowed to just a trickle - after 500ish miles it's only a hair below the fill line on the tank. I hoped that would be the end of it but another issue has cropped up.
The engine management light started to come on, with code P0300 (random misfire) and P0304 (misfire cylinder 4). I took it to the usual garage and was told that the most likely cause was the coil pack, which they replaced along with the plugs. They commented that the timing chain also sounded quite noisy.
The next day - light back on, same codes. I took it back, and after a little investigation including a test drive the mechanic concluded that there was no misfire, and that the play in the timing chain was causing the car to show the code for a misfire. They advised that the timing chain should be replaced at a cost of around £400.
My housemate uses another local garage and recommends it, so I popped in today to get a second quote. They said that in their opinion the diagnosis was rubbish and that a slack timing chain wouldn't show a code for a misfire. They quoted £800-1000 to replace the chain anyway, saying that they only did proper jobs and that I'd be better off burning the £400 in the garden then paying that for a timing chain change.
So I'm a little bit confused... I'm concerned that this is another symptom of the head gasket going and I don't want to pay £400 not to solve the issue! Could a slack timing chain cause the code? Is it worth doing? Any advice welcomed
I changed the coolant tank cap and the loss of coolant slowed to just a trickle - after 500ish miles it's only a hair below the fill line on the tank. I hoped that would be the end of it but another issue has cropped up.
The engine management light started to come on, with code P0300 (random misfire) and P0304 (misfire cylinder 4). I took it to the usual garage and was told that the most likely cause was the coil pack, which they replaced along with the plugs. They commented that the timing chain also sounded quite noisy.
The next day - light back on, same codes. I took it back, and after a little investigation including a test drive the mechanic concluded that there was no misfire, and that the play in the timing chain was causing the car to show the code for a misfire. They advised that the timing chain should be replaced at a cost of around £400.
My housemate uses another local garage and recommends it, so I popped in today to get a second quote. They said that in their opinion the diagnosis was rubbish and that a slack timing chain wouldn't show a code for a misfire. They quoted £800-1000 to replace the chain anyway, saying that they only did proper jobs and that I'd be better off burning the £400 in the garden then paying that for a timing chain change.
So I'm a little bit confused... I'm concerned that this is another symptom of the head gasket going and I don't want to pay £400 not to solve the issue! Could a slack timing chain cause the code? Is it worth doing? Any advice welcomed
t400ble said:
A grand to change a chain lol
£300 I'd expect to pay round here. Not a difficult job.
That's more like I was expecting - for some reason I got the impression they didn't want the job!£300 I'd expect to pay round here. Not a difficult job.
The big question is... can a loose timing belt cause a misfire code?! The first mechanic himself said he'd expect to see a cam code.
And a rather stupid question, but - if the head gasket was causing a loss of compression on one cylinder, would the misfire be noticeable?
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