Hello Forum

 

Not sure where to look for the

Fabia 1.2 petrol 54hp 66k miles petrol Engine coolant temperatures sensor 1 location?

possibly the Cylinder head?

As the P0118 code can appear and the engines not even warmed up, think sensor needs replacing.

 

Also have a P0301 cylinder 1 missfire which does illuminate the dash and reason the P0118 has been discovered.

P0301 might possible consequence of the P0118??

as the P0118 does not bring up an indication on the dashboard and could been going on for along time.

 

The car is only normaly used for a 6 mile round trip to town at low speed.

Have just replaced the spark plugs, spark plug in cylinder 1 black soot others two plugs clean.

Previously tried swapping ignition coils 1 & 2 fault still on cylinder 1 P0301 when the car packs up.

Air filter clean The old plugs were cheap nickle I have replaced with some iridium.

 

Since replacing the plugs rather than just cleaning plug 1 believe the car is running smoother after running for a few minutes.

I do not know how sophisticated a 2004 car would be could the car automaticaly adjust the timing with new plugs via ecu

as it did not happen straight away the ecu adjust new plugs?

 

Can a car this old reveal more via vagcom ecu reader?

 

thank you

iain

 

Temp sensor is in the black plastic coolant flange from which the radiator hoses emerge. Gearbox end of engine head.

With a 6-valver misfiring on one cylinder unattributed to plug or coilpack I would encourage you to have the cylinder compression checked before much else is done.

 

Hello Pete

 

thank you for the advice

I have taken couple photos of what i think is the coolant temperature sensor the electrics partly unpluged so spot purplein the photos

it was hidden partly from view with air intake hosing to the air filter removed

I was going to unplug the coolant temperature sensor  it so it does not give a false high temprature , (low resistance) as a temperary

fix while i see if the P0301 is now fixed after plug change.

The plug in one was sooty black (i have read over rich fuel air mix for some reason) rather than oil black if that makes adifference to the advice on the cylinder compression.

thank you iain

 

The plug is sooty due to the misfire, the misfire is due to low compression, the low compression is due to a burnt exhaust valve. There really isn't much else to tell you I'm afraid.

Edited 11 November, 20232 yr by sepulchrave

You have correctly identified the coolant temperature sensor, yes.

Sep may well be correct about exhaust valve damage, but best to check compression which is relatively quick and easy. 

Hello Forum

 

Finally been able to do a basic compression test 1.2 petrol 2004 Fabia 54hp 66k miles

The ECU indicates P0301 cylinder 1 missfire

After small amount of oil in each cylinder I only turned the engine over with the starter motor for the tests.

Compression test results

                                  Oil

Cylinder 1    50        100

Cylinder 2  130        180

Cylinder 3    50        100

Pressure was not lost from any of cylinders quickly, but i was turning engine so cannot say if the pressure

started low and remained low while turning the engine?

This engine is known to often get exhaust valve problems i believe

What supprised me cylinder 3 compression being as bad as cylinder 1?

As no code for cylinder 3.

Maybe the increase inpressure after oil was put into each cylinder is missleading normal for 66k engine.

If it was two adjacent cylinders eg 1 and 2 possible indicating headgasket fault, but its 1 and 3.

 

After adding oil will the cylinders piston rings return from 100 to 50 sooner than later?

 

I have read if pressure starts low and remains low indicates valves need look at this next.

 

Wishing you all a happy New Year.

Iain

 

 

Yes, those pressures are much too low, the head needs refurbishment.

 

I may have told you this a while ago...

I thought that you were sticking your neck out saying that at the time but credit where it is due 👍

 

I am surprised it would start and run with 2 out of 3 cylinders that low.

Thank you for all your input.

 

I did the pressure test to confirm an engine problem and for a better understanding.
There was a chance, or hope, that I had made an error; for example, I may think I had swapped coils but had not.
And I have never done a pressure test before.

Unfortunately, the car is not worth fixing due to cost and age.
But this Fabia does not have that high a mileage compared to other 1.2 petrol engines of a similar age for sale online.

 

For my better understanding, would you expect an increase in pressure in an older engine with oil without any engine fault?

3 hours ago, iain1234 said:

For my better understanding, would you expect an increase in pressure in an older engine with oil without any engine fault?

 

Yes, always, piston rings don't seal well until they've some pressure behind them or some oil to stop the air getting by even in a brand new engine.

 

The fact that all three cylinders reacted exactly the same, picking up 50 psi proves the bottom end is healthy.

Edited 1 January, 20242 yr by sepulchrave