General Oil consumption and petrol smell on the dipstick

[koalar]

Long term fuel trims are maxed out, normally indicates a misfire

Pulling the correct vacuum, timing, tappets and so on are probably okay

Post cat is pegged low, this isn't normal

 

[Indritk]

Long term fuel trims are maxed out, normally indicates a misfire
View attachment 454821

Do I have to check the spark plugs?

Pulling the correct vacuum, timing, tappets and so on are probably okay
View attachment 454822




Post cat is pegged low, this isn't normal
View attachment 454823

 

[koalar]

Spark plugs need checking sometimes anyhow

It's fairly common for them to be a cause of a misfire

The gap grow over time until it starts to fail

They start at 0.8 or 1 mm depending on brand and start to fail at around 1.7mm on the 1.2 engine, I guessing yours will be similar


Also a picture of the plugs in the order they come out of the cylinders sometimes is useful

My gut feeling will be oil pooling inside the inlet manifold, looking at the leak under the airbox

I visual check on the MAP sensor will normally confirm this, I'd there's oil on the tip performance will suffer

 

[Indritk]

Spark plugs need checking sometimes anyhow

It's fairly common for them to be a cause of a misfire

The gap grow over time until it starts to fail

They start at 0.8 or 1 mm depending on brand and start to fail at around 1.7mm on the 1.2 engine, I guessing yours will be similar


Also a picture of the plugs in the order they come out of the cylinders sometimes is useful

My gut feeling will be oil pooling inside the inlet manifold, looking at the leak under the airbox

I visual check on the MAP sensor will normally confirm this, I'd there's oil on the tip performance will suffer

Good evening,today I have completed the works changed oil and filter,spark plugs and a cleaning to the throttle body. I have done some photos to spark plugs in order from number 1 to 4 (number 4 is the last near the throttle body).. from the photos on the 4 injector I see some dirt I'm not sure if it's oil coming from the airbox into the injector or is the injector leaking because the other 3 are very clean.

 

[koalar]

What's the gap size

Looks large

Is this gasket present.

Can't see it in your photos

 

[bugsymike]

As @koalar says re the old spark plug gaps, we had a saying "looks like you could drive a bus through that gap"
New plugs correctly gapped will definitely reduce misfire under load.
Also with gaps that wide, under damp conditions it can encourage shorting from ignition coils and leads causing other failures. The wider the gap , the higher the voltage that the coil has to provide to jump the gap.
We used to prove that using a Crypton Diagnostic Oscilloscope in the old days measuring kilovolts in the four lines of the individual cylinders, simply fitting a new set would drop the voltage required reading on scope, also resister type plugs require higher voltages , so when we raced karts we opted for non resister type spark plugs.
Although not a direct effect on oil consumption, I would expect car to run better with the new plugs.
Another thought or two, there is a deposit on the old plugs, which we used to link to early head gasket issues, but as we saw it more often it maybe due to modern fuels. A sort of greenish tinge.
Secondly the originally plugs appear to be showing signs of overheating/melting of the centre electrode, are they the correct heat grade/specification for your driving conditions?

 

[Indritk]

What's the gap size

Looks large

View attachment 455043View attachment 455044


Is this gasket present.

Can't see it in your photos


View attachment 455045

I haven't measured it ..yes the gasket is present it's not on the photos because I took it of and cleaned.

 

[Indritk]

As @koalar says re the old spark plug gaps, we had a saying "looks like you could drive a bus through that gap"
New plugs correctly gapped will definitely reduce misfire under load.
Also with gaps that wide, under damp conditions it can encourage shorting from ignition coils and leads causing other failures. The wider the gap , the higher the voltage that the coil has to provide to jump the gap.
We used to prove that using a Crypton Diagnostic Oscilloscope in the old days measuring kilovolts in the four lines of the individual cylinders, simply fitting a new set would drop the voltage required reading on scope, also resister type plugs require higher voltages , so when we raced karts we opted for non resister type spark plugs.
Although not a direct effect on oil consumption, I would expect car to run better with the new plugs.
Another thought or two, there is a deposit on the old plugs, which we used to link to early head gasket issues, but as we saw it more often it maybe due to modern fuels. A sort of greenish tinge.
Secondly the originally plugs appear to be showing signs of overheating/melting of the centre electrode, are they the correct heat grade/specification for your driving conditions?

I don't know if the spark plugs were the correct one for the car it's first time I'm changing them since I bought the car..I have put the NKG one they are indicated a fit for the car

 

[bugsymike]

I don't know if the spark plugs were the correct one for the car it's first time I'm changing them since I bought the car..I have put the NKG one they are indicated a fit for the car

I am a fan of NGK spark plugs since working for a Mazda Dealership in the 1970s and found them 100% reliable.

 

[Indritk]

I am a fan of NGK spark plugs since working for a Mazda Dealership in the 1970s and found them 100% reliable.

They seem ok..since a changed the oil and spark plugs the engine seems to run more smoothly..the only thing that I'm concerned is the oil in the air box on the photo attached

 

[GrandePunto PL]

Oil consumption (blow-by) a bit too much. Do the pistons freeing procedure (pouring some engine flush into cylinders, then suck back - to avoid "poisoning" of the exhaust system). Stuck piston rings is a trademark of the FIRE family engines.

As for old sparkplugs condition: classic example of neglected/abused car! No preventive maintenance whatsoever.

 

[Indritk]

Oil consumption (blow-by) a bit too much. Do the pistons freeing procedure (pouring some engine flush into cylinders, then suck back - to avoid "poisoning" of the exhaust system). Stuck piston rings is a trademark of the FIRE family engines.

As for old sparkplugs condition: classic example of neglected/abused car! No preventive maintenance whatsoever.

Thank you for your advice ..I will keep an eye on the air box/throttle body for oil and if I see that after some time it will get dirty I will do this procedure

 

[koalar]

Now you changed the plugs

What symptoms are we left with

With the engine warm what are the long term fuel trims saying

 

[Indritk]

Now you changed the plugs

What symptoms are we left with

White the engine warm what are the long term fuel trims saying

I will make a video tomorrow and post it ...In the mean time I will keep a look on the oil consumption and the airbox/throttle body if they will get dirty with oil

 

[Indritk]

Hello Everyone,I have just made some video of the data showing now that I have changed the spark plugs and cleaned the throttle body..I have made another video when from what I see I think its leaking small amounts of oil

 

[koalar]

That's great

There's an improvement in the idle, it was fluctuating much more

The post cat O2 is now giving a sensible reading if a little high but not enough to worry about


The LTFT is no longer pegged high

 

[Indritk]

Thank you for your support can you please have a look on the last video I think its leaking small amounts of oil..its normal?

 

[GrandePunto PL]

Bad gasket (brand). Even RTV silicone didn't help (I can see grey one).
Good valve cover gasket will seal without any "support" (no adhesives whatsoever).

 

[Indritk]

Bad gasket (brand). Even RTV silicone didn't help (I can see grey one).
Good valve cover gasket will seal without any "support" (no adhesives whatsoever).

So basically I have to by a head gasket set and change it?

 

[koalar]

Looks to me like the valve cover gasket is weeping not seriously

I'd leave it for now,