Technical just about runs ,no power (help newbie)

[mikebentley1]

Hi All
Please Help, I'm a total newbie to Fiats !
My punto 1999 1.1 spi just about starts and just about keeps running with a lot of throttle , seems to be firing on all 4.
I've been told to try reseting the ECU by diconnecting the battey and turn the key to pos1 , would this loose the immobiliser code? (I don't have the red key)
What step by step diagnosis should I follow?
Many thanks
Mike

 

[Ziggy122]

The Imboliser code Shouldn't disappear by diconnecting the battery

If it does there is a big problem waiting to happen....

Anyway - If the engine runs with alot pedal to the metal action

Then it could be numerous things

Poor air Intake - a blocked air intake means it struggles to breathe/Run
Timing has slipped - its like your heart, it falls out of sync and its hard to do anything
Poor Fuel intake - Is the car able to suck fuel in? no fuel or little fuel can cause hard running
Blocked Exhaust/Cat - if the engine cant fart basically, the pressure can only build up


So Check the basic's
Oil water okay?
Air filter condition?
Spark plugs and HT leads in a reasonable condition? Not black coated?
Fuel able to reach with some pressure? Petrol Filter Not blocked?

ziggy

 

[DaveMcT]

Also compression tests and exhaust isnt blocked with gunk from short runs.

 

[mikebentley1]

Thanks guys
just a bit of background ,I bought the car with this fault (yes I know but I'm broke:bang
The previous owner said this happened all of a sudden.
I took off the air cleaner made no difference but smelled of petrol quite a bit.
He said he was told it was the injector ,what do you think?
I'll try a compression test first I think
Cheers
Mike

 

[s and b]

yes do a compression test before anything else

 

[fingers99]

As above. Unlikely to be the injector itself. Check the wiring to the injector for missing insulation (often where it passes through to the injector in the throttle body.

 

[DasArab]

Blocked Exhaust/Cat - if the engine cant fart basically, the pressure can only build up

This would be where id look too, very easy to check, just run the car(you may need help with this in your case) and go to the exhaust and see how well the gases are coming out the exhaust. If there is next to nothing id defiantly be looking to the cat. Quite often the Cat can collapse, ive seen this a few times on another forum im on.

 

[mikebentley1]

Hi All
Just to let you know I'm waiting for a compression tester to arrive from ebay:bang:
Cheers
Mike

 

[mikebentley1]

It's arrived ,just need to test the engine now, if it is HG what tools do I need?, I have 13mm, 10mm sockets, and spanners, screwdrivers and pliers but do I need anything else to change the HG ? (I can borrow a torque wrench)
Thanks
Mike

 

[s and b]

the compression tester will confirm or deny a worn engine
we are not looking for a head gasket at this stag
be careful taking out plug no3 as they are hard without proper tackle and you could damage the injector rail

 

[Ziggy122]

you need either a Spark plug socket
Or a Deep socket that fits the plug

Remove the plugs -
Brown = Good
Black = Rich
White = lean

Next disconnect the Crank Sensor, this prevents the engine from actually starting

Connect the tester to the glowplug hole - have a friend turn engine over
Note the reading it gives after about 3 to 5 seconds of turning over (write it down)

Repeat over all 4 cylinders

Then go back to the start again
Add about 15ml of Oil WD40 or Normal Engine oil
IF the piston rings or Bore's are worn, the oil will improve the reading
so repeat over all the cylinders and note there readinds down

then post them up here


As for a HG change
You need quiet abit of tools

A range of Spanners
A Range of Shallow Sockets
Deep Sockets
wood
Torque Wrench
Axle Stands
Jack
Sump plug set - oil filter wrench
Screwdrivers
Spark plug Set
HT Lead hook - only if aHT lead is determined to NOT come out
New Jubalee clips

Its a long process, the HG change itself, is quick
its the stripping down and supporting the whole engine that takes time
Its doable in a day
WITHOUT any Bolts rounding - which WILL happen
And other problems like locating Collets not fitting etc etc

Lots todo

ziggy

 

[mikebentley1]

Hi All
Thanks for the info, the engine is quiet worn 190,000kms ,but what pressures should I expect?
thanks
Mike

 

[fingers99]

The actual pressures are not critical. A difference between cylinders and/or a big difference between dry and wet readings is.

 

[mikebentley1]

Hi Guys
Did a compression test and got 100 ,75,75,80 psi. not sure if this was too bad so carried on looking ,has had a new cambelt 9 months ago so did't look at this first ,wish I had, it was quit slack , checked cam timing 3 teeth out! ,retimed and retentioned started first time! so ziggy122 you were right!
Thanks for all your help
Mike

 

[s and b]

must be guzzling fuel with figures like that though

 

[dav3y]

sounds like fuel and ignition to me.

replace the coilpack(s), new leads and get some new spark plugs.

what happens when you start it up, and litterally leave it to idle?

 

[thelad]

sounds like fuel and ignition to me.

replace the coilpack(s), new leads and get some new spark plugs.

what happens when you start it up, and litterally leave it to idle?

what? Did you not read the bit about that cambelt?

 

[mikebentley1]

Cheers guys
I don't know about consumption yet as I've only just got it going and the battery is old and was getting weak ,I'll retest it when I get a new battery on it.

What should a worn 1.1 read? whats good ,bad and ugly readings?
Thanks again
Mike