General Punto - loss of power and misfiring

[Maistan]

Hello, please can someone help - my 53 plate 1.2 petrol punto with 37,770 miles on the clock is giving me headaches - if I run her for short distances approx 6 miles a journey twice a day I have no bother with her BUT when I decide to be adventerous and take her on longer journeys this is where the problems start - this has been continuous for over 2 years -
My local garage had the fuel tank drained as they thought there was water in the fuel, they took out the filters on the fuel tank and cleaned them but on short journeys no problems -

but if you drive for about 100 miles she starts to be unresponsive with no power even when the accelorator is fully depressed, it misfires and judders and then all of sudden it clears and she drives with no problem at 60mph until you slow down and change gears the same happens again even the engine can cut out especially if you are at a junction and there is no power leaving you stranded until you get the engine to go again - no warning lights appear on the dashboard - even the AA man could find no faults on the computer

Please can someone give me a clue as to what to do - someone has suggested the coolant coils could be faulty

 

[Ziggy122]

Please can someone give me a clue as to what to do - someone has suggested the coolant coils could be faulty

coolant coils?
Who ever told you that - must be shot / Never listened too for advice
There is no such thing as coolant coils

When hot you loose power and stall, which is a sign of crap compression
I'd say get a dry then wet compression test - and come back here with the figure
But i'd be tempted to say my next set of points, as only 38k on the clock is way way way to early for compression problems - unless something else like valve damage has occoured - which isn't common as the 8v is a safe engine, so valve damage is rare

Other things
the juddering is a misfire which essentially is No power
So Check Sparkies and HT leads
Do a Coil Pack test - See the guides section
If it starts getting Shakey and slowly dies then wont start till cool could also be the Crank sensor, It must be able to clearly see the Bottom Pulley to give a spark, they are known when hot to slowly fail

Hope this helps

Ziggy

 

[Maistan]

Took my car to garage to be told yet again there was water in the fuel tank - can this be causing this problem and how the hell does the water keep getting into the fuel tank -the tank has a lockable fuel cap and they have checked the tank for holes etc - I surely can't be the only car that uses Tesco's and gets water in the fuel - will take it again on another 100 mile journey next week - I am not convinced this has sorted the problem but the garage are adamant - any advice about what I do next bearing in mind this is causing me serious cash problems so I cant afford to take it to another garage.

 

[thelad]

At this time of year i would stick to Esso,bp or shell, supermarkets tend to put alot of crappy adatives.

 

[Ziggy122]

At this time of year i would stick to Esso,bp or shell, supermarkets tend to put alot of crappy adatives.

i run supermarket Fuel all year - every year
nothing wrong with just plain vanilla Fuel

Sure yes BP/shell add a few addertives - but whup tokin freak do?

As for water in the Tank - i too dont believe it
Even in the coldest of colds - not much moisture will form in the tank if its sealed
Also weather it be 6 miles or 120miles
If there is water in the tank - you'd notice the effect all the time

i'd like to say fuel filter - but again you'd notice that all the time

For something to be worse when Hot and Not cold
I'd be tempted to say either the MAP or lamba sensors really
Lamba could be dead - but no fault code yet - and over fueling
it takes time to clear - but the Cat COULD be chocka

Cat Failure could also be a potential Cause

Again - have the Spark Plugs been checked for decent sparks?

Another thing that could be affecting is compression
When an engine is hot, the compression could drop a little casuing a "dying" sensation

Ziggy

 

[Maistan]

Thank you Ziggy - will start with new spark plugs- have not been changed for 2 years - watch this space ................

 

[Atticus!]

Take it from someone who has had every engine problem under the sun with my Punto.

Change the cheap **** bits first.

I had this same problem many times and its always turned out to be something stupid.

Change your crank and Cam Sensors as these get coated in crap and overheat and generally become useless. (cheap ones off ebay will do)

Failing that think about it logically..... how is your engine powerd work your way forward from the Coil packs up to the leads and then the plugs.

Failing that it might be the fueling system, so again start off cheap, try some injector/ fueling system cleaner, then work your way throught he fueling system, check for kinked hoses/ blockages, fuel pump replacements and injector replacements, 9 times out of 10 a good flush out with injector cleaner will work.

After all this if it isnt fixed then try replacing the ECU as they can get fryed and cause issues that cant be seen clearly.

Also have a set route planned out, for example count how many times your drive round your block before any problems start, then see if your can go any further after changing a certain element.

All this is the cheap way to go, if youve got a wad of spare cash take it to a garage.

Hope that helps.

 

[thelad]

Change your crank and Cam Sensors as these get coated in crap and overheat and generally become useless. (cheap ones off ebay will do)

never heard of a crank sensor overheating

 

[Ziggy122]

what he means when the sensor Gets Hot (from been on the engine)
the internals Expand - like most things do
And jus like that - the sensor Fails

Ziggy

 

[Azzam]

my 16 Valve misses when its cold for a second (when I put my foot down) so im going to give it a good service As Ive only cleaned the plugs every2 month. I have also noticed some days its more_ responsive on some days and someday its flat

 

[sixpotman]

Water in the tank-
Your only doing short journeys the petrol fill ups are
probably a month apart. Remember most modern petrol
now contains ethanol ethanol absorbs moisture from the air.

Air vent system to the tank includes a carbon canister
where tank vapors are held until the engine warms up
fully and then drawn into the inlet side of the engine
low miles car does not warm up the canister can get
blocked and could be part of the air vent system to the
petrol tank - no vent petrol starvation for a short period
of time.

John

 

[Maistan]

Thank you John - very interesting - will ask the garage about this

 

[mk1Punto9675sx]

i run supermarket Fuel all year - every year
nothing wrong with just plain vanilla Fuel

Sure yes BP/shell add a few addertives - but whup tokin freak do?

As for water in the Tank - i too dont believe it
Even in the coldest of colds - not much moisture will form in the tank if its sealed
Also weather it be 6 miles or 120miles
If there is water in the tank - you'd notice the effect all the time

i'd like to say fuel filter - but again you'd notice that all the time

For something to be worse when Hot and Not cold
I'd be tempted to say either the MAP or lamba sensors really
Lamba could be dead - but no fault code yet - and over fueling
it takes time to clear - but the Cat COULD be chocka

Cat Failure could also be a potential Cause

Again - have the Spark Plugs been checked for decent sparks?

Another thing that could be affecting is compression
When an engine is hot, the compression could drop a little casuing a "dying" sensation

Ziggy

Hi.. At the moment I m having a similar problem where the car cuts out and struggles to accelerate between 2500 and 5000 RPM and difficult to get going from standstill, however it seems to run better the warmer the car gets... can it still be caused by crank or lambda sensors or could it be other sensors like the coolant temperature sensor and ICV

thanks in advance for your time

 

[Ziggy122]

Hi.. At the moment I m having a similar problem where the car cuts out and struggles to accelerate between 2500 and 5000 RPM and difficult to get going from standstill, however it seems to run better the warmer the car gets... can it still be caused by crank or lambda sensors or could it be other sensors like the coolant temperature sensor and ICV

thanks in advance for your time

Struggling to accelerate at load sounds.more like coils to.me....


Ziggy

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