Technical Fiat Punto Mk2 Petrol 1.2 16V not starting

[varesecrazy]

error post..

Thanks Jack

 

[jackwhoo]

IF you need it to drive home

Tape it up and slide finger of a Marigold glove over it

Path of least resistance is still the Plug gap

I think this is for different thread

 

[varesecrazy]

I think this is for different thread

Good point

 

[crankshaft]

You need Fuel, you need a spark, you need air and you need compression. If you have established you have fuel and a spark, the next logical step is to make sure you have air and compression which a compression test will tell you. Continually trying to start the engine is just going to flood the cylinders, wash the oil out of the bores and risk causing damage to the engine.

At least it's unanimous that the engine lost compression.
It was working just fine the day before, but I am guessing that's how a lot of stories start.

So, this idea that the sooth or debris will burn away and the engine will go back to normal, is not really realistic?

I understand the importance of a compression test, but I don't think is something that I would be able to fix myself. So at that point is just better handing the car over to a repair shop. Or giving up on this engine, and looking for a second hand one.

wash the oil out of the bores and risk causing damage to the engine.

If the oil washes out? How can it get back in there?

I don't know if this helps any. But after trying to start the card for a bit, I removed the spark plugs, in the hopes the fuel evaporates, so I don't flood the engine. Unplug the harness for the injectors, and turn the motor, using the starter, so air evaporates the fuel further. I am hoping to not have flooded the engine so far.

 

[crankshaft]

A how to, for running a compression test on this engine, slightly older engine but the process and the basic engine is the same.

I just noticed it's your Youtube channel. It's a pretty good video, easy to follow. Kudos
And the engines between Punto mk1 and mk2 look about the same, didn't know that. Is this the FIRE engine? I have heard that name before.

 

[varesecrazy]

FIRE yes all versions of the
Fiat
Integrated
Robotised
Engine

Started @1984 (and using @30 less parts than older engines)

Pretty tough, but Headgaskets don't tolerate lack of cooling

 

[boguing]

Are you sure you've got the plug leads on the correct plugs? I don't know this engine/coil pack but I'd imagine that the pack is numbered by the connections?

 

[varesecrazy]

Are you sure you've got the plug leads on the correct plugs? I don't know this engine/coil pack but I'd imagine that the pack is numbered by the connections?

And #4 is the battery / gearbox end

@crankshaft

 

[crankshaft]

Yes, I already double checked.
The coil pack has the cylinder numbers printed on it 1 to 4.
I checked many times, 4 is the cylinder on the battery side. 1 is near the timing belt.

 

[PuntoHowTo]

I just noticed it's your Youtube channel. It's a pretty good video, easy to follow. Kudos

Thanks, Yes the engine used in My Mk1 Punto Cabrio is basically the same engine as in your car with very little difference.

 

[boguing]

I've re-read your opening post again. I'm sure you did, but you didn't mention re-connecting the injectors after blowing the cylinders out (you'd probably have fuel spraying everywhere if you hadn't). I can't see anything else there that would be causing it to have got worse so hate to say it but if you haven't already I'd walk away from it for a day and come back and check everything for mistakes with a clearer head.

Going back to the rough idle which started all this, did you hear any different noises? A stuck inlet valve can sound like a chuffing noise from the air filter and a burned exhaust valve more of a spitting noise from the exhaust. You may not have a compression tester, but if you get some sort of stick/rod with a bit of rubbery stuff that will cover the plug hole you will fairly easily tell if one cylinder is different from the rest. Won't solve your starting problem, but...

A last thought, and again, I don't know this engine. I presume you had the air filter off when you blew the cylinders out with a compressed airline? Anyone know if there's anything in the inlet tract that could have been unhappy about reversed flow if an inlet valve was open at the time?

 

[judderbar]

1. Checked that there is pressure in the fuel injectors rail, I don't have a value for the pressure, but pressing the valve on the rail, with a screw driver, fuel comes gushing out

There should be 3 bar there. When you say fuel comes gushing out that does not sound right to me. There is quite a bit of pressure there. Sufficient for it to be intimidating to press that valve. It is a bit awkward but it is possible to take the injector rail off and keep it electrically connected so you can crank the engine and watch the injectors spraying into some containers. Each injector has a built in filter. It is possible to reverse the injector in the injector rail to get petrol to come out in reverse thru the filter

 

[crankshaft]

Sufficient for it to be intimidating to press that valve.

Yes, when I pressed the relief valve a burst of fuel sprayed all over my hand. I can't say if it was 3 bar, but it had quite some pressure.

 

[crankshaft]

(...)but you didn't mention re-connecting the injectors after blowing the cylinders out (...)
but if you haven't already I'd walk away from it for a day and come back and check everything for mistakes with a clearer head.

I only unplugged the electrical harness of the injectors, I didn't removed them from the injector rain/manifold.
It's a good advice. I haven't been working on the car today. But... still no new ideas.
Would be great to have the car running this monday, but is not happening.

Going back to the rough idle which started all this, did you hear any different noises?

I don't remember listening to any unusual noises.

I presume you had the air filter off when you blew the cylinders out with a compressed airline? Anyone know if there's anything in the inlet tract that could have been unhappy about reversed flow if an inlet valve was open at the time?

Yes, I had the air filter off. I had previously removed the intake manifold, some 4 years ago, and there I can't see anything that would be upset about that. Despite maybe the intake valves?

 

[crankshaft]

The mechanic told me to keep trying to start the car. That is probably sooth inside the engine that is jamming the valves, and the car will start and clear the "debris". The origin of these debris or sooth is from me cleaning the spark plug threads on the engine head.
I am gonna try to use Starter Fluid to see if I can start it before the battery dies out for good.
Do you guys think this could work?

Good news, sort of...
I tried to use starting fluid, took like 6 attempts, but the car finally started and stayed on.
Drove the car about 50 Km, with time, the rough idling and running rough returned.
At least the car turns on every time now, so I guess the dirt/sooth inside the combustion chamber caused a lack of compression, or something.

Still have a problem with the car running rough.

 

[George1982]

Have you checked for any massive air leak eg cracked manifold or intake gasket leak?

 

[PuntoHowTo]

Something is very clearly not right. I still very much doubt the Soot Claim.

 

[crankshaft]

I end up driving 150 km (around 93.2 miles for the imperial minds).
The car starts every time now, even after being cold. Doesn't seem to have any issues starting.

However, there are more issues now, the car has a clear loss of power, takes longer to accelerate and reach speeds.
At idle the car shakes. When accelerating in a highway, it's possible to feel the car shaking. The engine is always shaking, is not like a momentary "hiccup", it's continuous shaking.
I checked the coolant level, before and after driving, and it is at the same level - the maximum mark.
I was waiting for all the oil to drain back to the sump, but it seems to be at the same level mark.

When I left home this morning the car was running smoother than what it is now.
About 120Km into my trip, the engine management light started flashing in the instrument cluster, I was driving in traffic at the time, it eventually stopped flashing, and remained off. It came back when I was driving in the highway, at higher RPMs, flashing again. It stayed flashing for 10 Km, and then went back to off.
I haven't plugged my laptop yet, but I already suspect misfires.

Going back to the rough idle which started all this, did you hear any different noises? A stuck inlet valve can sound like a chuffing noise from the air filter and a burned exhaust valve more of a spitting noise from the exhaust.

I can hear a sound from the exhaust pipe, is hard to describe it, but that noise is also audible at a different tone in the engine itself.
I read online that there is a test you can do in the tail pipe, with a paper, to see if the exhaust pipe is also sucking in air.

Something is very clearly not right. I still very much doubt the Soot Claim.

What you suspect it might be? A stuck valve? Maybe a head gasket? The engine seems to have regained compression. Honestly I don't know how weird, or incorrect the claim might be.
I am using the word soot, but maybe that's not the best description. That theory was based on my descriptions of the problem to the mechanic.
I told him that I could see on the cylinder #1, that small pieces of whatever "dirt"/"goo"/"soot"/"(whatever the right word is)" that covers the top of the piston had become loose, and the top of the piston was metal shiny now, which was not the case for the other 3 cylinders. Before I swapped the spark plugs all 4 cylinder looked the same, see through the small "window" of the spark plug hole. I think this soot has a brownish color, maybe it's also partly rust? I am color bling, so is hard to be too sure.
When turning the engine, using the starter motor, and looking down on the pistons, through the spark plugs hole, I cold see small small pieces of soot jumping around. A small piece even jumped out to the spark plug well, and got sucked back into the combustion chamber as the piston whet up and down.

 

[crankshaft]

Have you checked for any massive air leak eg cracked manifold or intake gasket leak?

I have not checked for intake air leakes, besides visually inspecting it.
But I feel the car vibrating a lot when driving at higher speed, with the engine at high RPMs, I thought that would point to something else other that a vacuum leak?

 

[boguing]

I've only ever had one coil pack go bad, it was on an '02 Punto 1.2 8v and that only started acting up when the engine had got properly hot. Symptoms were as you're describing. I know the one you have is only six years old and that it would be bad luck......