Kia Compression test.

[steveuk23]

Hi guys.
I've been having issues with my MK2 Kia picanto engine lately.
Going off what I've read it may be a number of things from Piston rings, Valve stem seals or head gasket.
I can go Into more detail if you want but for now I was just double checking with you guys on the process of doing a compression test.
Am I right in thinking I do it in this order...
1.remove spark plugs
2.disconnect fuel relay.
3.attach tester and turn the car over until the needle stops going up on the tester ?
4. Repeat on the other 2 cylinders.
I've seen things mentioning that I should press down on the accelerator while turning the key is this right ? And also if ones low add a bit of oil into the cylinder and repeat the test see if there's a improvement.
Cheers

 

[rs500nutter]

Everything on your list is basically right.
Cant see what's the point of pressing down on the accelerator because fuel aint needed to do the test 🤔🤔🤔.
Just make sure you're at Zero between cylinder test's and adding a bit of oil may or may not increase the pressure in that cylinder depending on the condition of the piston rings.

 

[xero50]

You basic procedure looks OK (items 1 through 4).
Personally I wouldn't worry about the throttle or adding any oil. Doing a compression test is allot easier if you are assisted by someone else who can turn the engine over whilst you observe the tester's readings.
Look for any material difference in the pressures achieved compared to the other cylinders. (they will all be a little different to each other even in an ideal world, what you are looking for is a "sore thumb" which will lead you towards where the problem is located).

If you suspect that you have worn rings or valve-guides, or seals, then a symptom of excess crankcase pressure should be apparent. Most engines run with a bit of crank-case pressure, but if there is excessive internal wear/damage somewhere then the gases which should normally be kept within the combustion side of things will find their way into the crank case. Test for this with the engine running at idle, remove the oil filler cap and place your hand over the hole to simply feel and observe how much "push" there is exiting.

If you suspect that there is a problem with the head-gasket: This can be a little more tricky to diagnose. Again, excess crankcase pressure may be apparent if and only if the internal pressures are finding their way into the crankcase. It is also possible that the pressure can find their way into the cooling system, in which case your radiator hoses will become very hard very quickly. To test, feel/squeeze the top and bottom radiator hoses. Then run the engine at idle until warm, and then feel/squeeze the hoses again (they will be hot/warm), but very hard/solid if combustion pressures are finding their way into the cooling system. Other symptoms of headgasket failure can be (but not always) oil contamination in the coolant, and water contamination in the oil, (after a while it looks like you have a load of unpleasant mayonaise/salad-cream has found it's way into the engine and/or coolant), loss of coolant, and an apparent 'making' of oil.

 

[steveuk23]

Thanks guys for the replies and @xero50 for the details that's great.
Hopefully I can narrow it down with the test now then.
Basically where I'm at with it at the moment...
Here's a list of the the things I know aren't right.
Back box exhaust blowing slightly.
Using excess oil without any noticeable oil leak especially near the head gasket.
Sometimes a lack of power when trying to accelerate then it will kick in.
Sometimes heavy smoke , mainly when setting off downhill for some reason and it's a grey colour not blue or black etc.
No white substance at the oil cap or anywhere else from what I can tell.
I know the water needs changing in the radiator as it doesn't look good, wouldn't say oily just dirty so I was planning on doing it this weekend if the weather holds up.
Thanks again 👍🏻

 

[rs500nutter]

Have a good look at your spark plugs when you remove them for traces of oil etc.
Also check the PCV valve is operating how it should and not choking the engine.
Excessive oil being burn't away is usually down to worn valve stem guide's or seals or extreme worn piston rings etc.
Thats if there is no visible sign's of oil leaking from gaskets etc.

 

[steveuk23]

Hi guys update on my compression test.
So they read
195 psi
193 psi
196 psi
So to me that seemed ok as the manual says 198 psi is the ideal , what do you think ?
The spark plugs looked good to me also no oil on any of them.
I'm guessing that's a indication that it could be the stem seals or piston rings then and not the head gasket.
I have added one of them additives to the oil that's meant to help with "oil leaks or revitalise seals" I'm really expecting much from that.
I have bought another car a month ago so this doesn't have to be used much now so I have thought about parking it up and trying to fix it myself even if it took me months.
I have changed a cam belt before but never been inside a engine and it looks like quite a big job.
Any suggestions would be great
Thanks

 

[cactikid]

Jesus i must be old , press down and hold Acl. pedal down while cranking engine was to let more airflow through butterfly flap usually that thing inside of what the cable goes onto.
First thing i would have done was look at spark plugs for deposits as that tells a bigger story of what an engine is doing.
Test is good for all cylinders.
If valve stem oil seals were an issue starting up in the morning blue smoke would be visible as oil is in the chamber.
One reason why routine oil and filter changes is important for the life of your engine.

Oil leaks you need to search upper and lower parts of engine for wet areas and possible oil light and oil filter weeps and dripping sump plug.

Diagnostics might need to be run for hidden issues and nothing seen so far needing digging into the engine

Just to add Headgasket can also go and not build up pressure in coolant system but by failure in seal between head and block for oilway high pressure. Eg Peugeot have a dire oil leak there and leaves a very big mess.

You mention colour of coolant and needs changing , some cars when replacing cam belt the waterpump is driven by the belt and is needing changing and fresh coolant is needed.
What colour is your coolant and are you topping it up lately ?

 

[steveuk23]

Jesus i must be old , press down and hold Acl. pedal down while cranking engine was to let more airflow through butterfly flap usually that thing inside of what the cable goes onto.
First thing i would have done was look at spark plugs for deposits as that tells a bigger story of what an engine is doing.
Test is good for all cylinders.
If valve stem oil seals were an issue starting up in the morning blue smoke would be visible as oil is in the chamber.
One reason why routine oil and filter changes is important for the life of your engine.

Oil leaks you need to search upper and lower parts of engine for wet areas and possible oil light and oil filter weeps and dripping sump plug.

Diagnostics might need to be run for hidden issues and nothing seen so far needing digging into the engine

Just to add Headgasket can also go and not build up pressure in coolant system but by failure in seal between head and block for oilway high pressure. Eg Peugeot have a dire oil leak there and leaves a very big mess.

You mention colour of coolant and needs changing , some cars when replacing cam belt the waterpump is driven by the belt and is needing changing and fresh coolant is needed.
What colour is your coolant and are you topping it up lately ?

Thanks yeah I forgot to say I changed the coolant and it actually seemed ok to me and the level hasn't changed in ages I can't remember the last time I topped it up to be honest it's been that long, the colour of it seemed clear and I didn't notice any oil or rust etc.
There's definitely not any blue smoke when starting the car in the morning thinking of it I don't think there's any smoke I'll check tomorrow.
I did take pictures of the spark plugs but not sure how much you can make out from these but I've attached them.
I've just remembered actually the engine light came on late last year and I cleared it with a cheap obd reader I have the codes were.
P0410
Powertrain
Secondary air injection system

P1000 - Powertrain

thanks again for the help.

 

[cactikid]

You can see the slightly oily sooty deposit on plugs , any brown marks on the ceramic of plugs can be a guide of how old they are.

Run another scan and see what new faults are listed now.

 

[steveuk23]

So it looks like I'm going to have to take the car in to a garage.
Last night my wife was setting off at some lights and she said a large cloud of smoke and the huge lack of power and car jumping etc.. then some more smoke and it settled down.
The smoke always seems to be at its worst at a certain point going home so it's a downward hill with traffic lights at the bottom and web setting off there's always more smoke then anywhere else.
I went out in it last night to try it out and it didn't seem too bad but the exhaust seemed louder like it was really blowing and the engine seemed like it was mis firing as there was a noise every few seconds but nothing shown on the obd I attached.

 

[cactikid]

What colour smoke and have you checked oil and water levels when cold?

Is the engine shuddering on tick over when under the bonnet.

Does that car have bolt on pencil coils on the plugs or dry coil and plug leads.

Might be looking at tips of plugs again.

With the exhaust issues as not sure if your car has a flexy neck as from rocking back and forth they do break and are noisy
Is the sound under the bonnet or underneath or back of car as short distance driving will rot quicker.

 

[pabloescaban]

Lack of power and plumes of smoke sounds like a fuel issue to me.
Has someone put the wrong or different fuel in it in the past few months?
Have you checked the fuel filter?

I'd put a bottle of Redex in next time you fill up and take it for a blast down the motorway for an hour

 

[steveuk23]

Hi sorry I didn't get notifications for the replies.
So the smoke is a light grey but has a very rich smell of petrol.
It's definitely not had the wrong fuel as it's only me who fills it up but no I've not changed the fuel filter is years if I'm being honest as i was never sure of the procedure or exactly how to access it.
Yep the ignition are the pencil kind that bolt on and also yeah it has a Flexi part on the exhaust.
I know it needs a new exhaust and been quoted in excess of £350 as a few places have said I need both the back and front now (which includes the flex) , the sound was coming from the back end it was definitely a exhaust blowing sound as I've had that in the past but not loud enough for people to hear when I'm driving.
But I just feel like I don't want to commit a too much money if it might have engine issues.
I'm going to check the levels when I get home as it seemed like it was overheating last night as the coolant temp was reading 90° and the fan came on after a short 10 minute drive.
Sorry I know it's hard to diagnose when you can't see the car.
Thanks for the help so far.

 

[cactikid]

90 is mid way on temp gauge is it not as thermostat could be 88 -92 and as its kind of Summer engine will heat up more quick and rad fan cuts in more which is normal.

Middle of Winter its harder to get to rad fan to work as cold air cools it down quick.

A quick check with miss in engine is to lift pencil coil up while engine is running to see if it misses more or stays the same if working .
Swap pencil coils over and see if the miss moves to that cylinder pointing to a faulty coil.

Failing that a possible fuel injector issue could be checked by unclipping it from injector .
Working injectors normally click when working and if you had a long screwdriver listen to it in your ear.

Would not be surprised with severe rust on exhaust.
Might have to get a centre box made for my 1989 car

 

[rs500nutter]

Them spark plugs have definatly seen better days 🤣🤣🤣🤣🤣

 

[steveuk23]

90 is mid way on temp gauge is it not as thermostat could be 88 -92 and as its kind of Summer engine will heat up more quick and rad fan cuts in more which is normal.

Middle of Winter its harder to get to rad fan to work as cold air cools it down quick.

A quick check with miss in engine is to lift pencil coil up while engine is running to see if it misses more or stays the same if working .
Swap pencil coils over and see if the miss moves to that cylinder pointing to a faulty coil.

Failing that a possible fuel injector issue could be checked by unclipping it from injector .
Working injectors normally click when working and if you had a long screwdriver listen to it in your ear.

Would not be surprised with severe rust on exhaust.
Might have to get a centre box made for my 1989 car

Thanks I'll try that.
I took the plugs off last night to have a look and they were far worse then last week in them pics above.
I had a old (but quite good condition) set of plugs spare so thought I'd try them and it helped loads.
I took the air intake hoses off and cleaned the butterfly thing (sorry can never remember the name) with some carb cleaner and I've drove it to work just now and it drive ok ish I did notice slight smoke.
I might call and get a fuel filter and replace that, I'm not sure what you mean by listening with a screwdriver ha ha.
Is there a special procedure to changing fuel filters or just a case of undoing and putting the new one on ?
Thanks

 

[rs500nutter]

Not 100% sure the location of the fuel filter and whether its an external filter or in tank filter 🤔🤔 if its an in tank filter access is usually under the back seat base.
Always pull the fuel system fuse before working on it ok .

 

[steveuk23]

Not 100% sure the location of the fuel filter and whether its an external filter or in tank filter 🤔🤔 if its an in tank filter access is usually under the back seat base.
Always pull the fuel system fuse before working on it ok .

Hi yeah I've found a manual online and it's underneath the seat at you suggested.

 

[steveuk23]

Hi guys I bought a endoscopic Camera of Amazon to have a look down into the pistons and it's not looking good.
It's covered in oil on top of the piston and where the spark plugs go.
So is that piston rings then or valve guide seals.

 

[cactikid]

Imagine piston as if it was oil seals it would burn off when engine running , oil on piston cannot burn off excess and stays wet.

Its not clogging up plugs yet but deposits are there.

We would throw a can of Lucas Oil Stabiliser into it when low as helps lube and lessens loss.