2003 Fiat Punto HGT Abarth doesnt like starting

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mvr, Feb 14, 3:17am
Mr Jazz and any others who know about these specific cars,
your thoughts would be greatly appreciated!

So our car doesnt like starting first pop, it's like it wont catch.
It will usually start 2nd turn or if you let it tick tick tick over for ages but I dont like doing that.
It has had the Variator and Cambelt etc done,
(and from what Ive learnt from owning this car, there are a LOT of mechanics even supposed Euro ones that dont do the variator on these cars when they do the cambelts! )
it has an aftermarket pod filter,
it's had the throttle body butterfly thing cleaned and new spark plugs when it was serviced last year. didnt make a difference.

It starts better when its warm, so if I drive the half hour out to my mechanic it starts fine lol!

So I'm wondering about a few things .
air flow? new pod filter needed? although this one has been cleaned,
MAF sensor needs cleaning?
fuel pump on the way out? Another thought on the fuel pump theory is basically once that fuel light comes on you have to fill it up ASAP,
as it will stutter and play up a bit on hills or when you put your foot down. Only does this when low on fuel.

The car is a lot of fun to drive!
It's black, tinted windows, lowered, black rims, get lots of compliments on it! Not overly efficient on gas but it is a 1.8ltr engine, we get about 400/425kms before the light comes on doing around town driving, so about 10km per litre,
compared to our other more sedate 1.2ltr which gets 15km per litre round town.

thejazzpianoma, Feb 14, 3:30am
Gidday again mvr.

I like to take a scientific approach to these things as much as is practical rather than taking too many "pot shots". So if it suits you I would be keen to walk you through a few easy tests if you are up for it and see if we can narrow it down.

Firstly, you are right to suspect the fuel pump, many of that era Fiat are fitted with VDO/Siemens pumps which I find do tend to need replacing around 180K. Can't say I have had exactly those symptoms from a dieing one though, and I have replaced a few in my time.

So. first test would be, grab a can of MAF cleaner (which is handy stuff to have on hand anyway). Pull the air filter off so you can get access to the throttle body, then have someone turn it over cold while you spray a couple of puffs in the throttle body. If it starts straight up we can then assume straight away that it's fuel related. If not then the next logical move in my opinion would be towards crank sensors, spark etc.

BTW. just in case you don't follow. MAF cleaner is highly combustible, what we are doing is introducing a fuel source other than petrol from the tank. The car will happily run on it, if it has compression, timing and spark. Obviously be careful, don't put your face close etc, if it catches a stray spark or ignition source, backfire etc it will flame up so take care.

The key thing to remember is you need the following to start the car:
* Compression
* Spark
* Timing
* Fuel
* Air

I like to come up with tests to suit the tools at hand to best test those things, starting with what's likely/easy first. In your situation I think the fuel would be a good one to start with.

Also, do use MAF cleaner, it's a safe option that won't poison your MAF or do any harm. (Can't remember how the exact air cleaner layout is on the 1.8 so it's pretty safe to use wherever you can insert it).

Best of luck, if you decide to give that a try and want to report back I will happily walk you through what's next.

Also. if you could have someone have a listen to the fuel pump when you turn the key on. It should immediately run a few seconds then stop, if it keeps running or doesn't run that's also a sign that could be the issue.

I am assuming you don't have multiecuscan BTW?

franc123, Feb 14, 3:34am
What is this tick tick tick you refer to? If the battery voltage is dropping too low during cranking either due to a battery being on the way out or else a poor cable connection in the supply or earth cabling that could cause all sorts of issues with the starting and fuel management systems., even if it still starts eventually.

thejazzpianoma, Feb 14, 3:36am
My other initial thought is to check the tank is not air locking with a blocked vent. Try starting it from cold without the fuel cap on. (pretty sure you can with a Punto)

One other likely fuel related theory for the low fuel issue could be the non return valve that keeps some fuel around the pump motor when the fuel level is low may be leaking. This could cause the pump to overheat and would explain why you have issues at low fuel levels.

Anyhow, if you do the MAF cleaner test we can then tell straight away whether we need to look further in to the fuel situation.

Normally you would use a scanner or gauge to check fuel rail pressure but I am assuming one is not available. Also I am not sure that the Punto reports fuel rail pressure, even with multiecuscan.

thejazzpianoma, Feb 14, 3:39am
I am off for a bit now, will have a look and see what your thoughts are later on.

mvr, Feb 14, 3:39am
OK cool I will get a can of the MAF stuff tomorrow and give that a go!

The car has done 112k.

re: listening to the fuel pump - that would be the slight whirring/humming noise when I turn the key half way? yes it does run a few secs then stop.

a 'multiecuscan' what?! I'd say no I dont lol.
Last year after I bought it and had to get Variator done (and the cambelt again even though it was only 10k old grrrrr! ) it was scanned and only thing that came up was the variator. It was doing this starting thing then.

mvr, Feb 14, 3:42am
franc123: sorry the tick tick tick I was referring to was when you turn the key and the engine wont catch, not an actual metal or something noise.

Although that is another thought - I dont know how old the battery is, so maybe that could have something to do with it?
Although that wouldnt explain why it seems to start fine if its warm? would it?

jmma, Feb 14, 3:43am
Oh one in the afternoon, I had a bit this morning Lol (o:

thejazzpianoma, Feb 14, 3:44am
Multiecuscan is software you run on your PC that lets you plug a cable in and get pretty much dealer grade diagnostics for your car. It's well worth purchasing given you have two Fiats. It's about $80 plus a few dollars for a cheap cable from ebay etc.

You can buy it online from the developer, the $80 gets you a years free updates but it will keep working long after the year is up.

Yes, that sounds like the whir in question, have someone listen by the base of the rear seat, should be quite loud there as that's where it's located. It's a shame you are not local to me as I usually plug my scope in and can see when the pump is worn and on it's way out from the waveform it produces. It's a super quick easy test.

I am sure we can work with what you have though and locate the issue.

mvr, Feb 14, 3:47am
Hmmm I just tried starting it with the fuel cap off,
and it started easily!
and the car has been sitting all day,
although its not exactly cold this afternoon in Auckland lol!

I will try this again in the morning when it is colder and see what it does!

thejazzpianoma, Feb 14, 3:49am
Those variators usually go about then on Fiats/Alfa's. It's standard practice to replace them or put a kit in at timing belt time. The kit is only $20, but you have to do it before you hear noise coming from the variator.

I am a little surprised though in that the later ones usually last better as the design was revised slightly. However, this would be largely dependant on how well it was service previously and what oil was used.

Anyhow, must run. Catch you later.

thejazzpianoma, Feb 14, 3:50am
Yes, and if it does, do it for the next few cold starts. We can then look in to what the tank vent situation is on those. From memory they don't run a fuel return but have the regulator on the pump. I am no fuel pump guru but to me it would make sense that such a system would be very susceptible to a blocked air vent.

Catch you soon!

mvr, Feb 14, 3:52am
re: leaks .
it does have a very tiny slow leak at the top of the radiator hose that goes from the bottom of the radiator up to the engine,
not enough to even drip down onto the driveway - I only saw it when I was playing with the pod filter and saw down the bottom some green fluid.
We just keep it topped up and its fine.

mvr, Feb 14, 3:54am
Cool thanks Jazz, see ya,
have a great Saturday!

thejazzpianoma, Feb 14, 5:17am
Gidday again, just popped in for a quick break. Was having a think about this, if the car seems to start fine with the fuel cap off, as a next step in proceedings I would try swapping the fuel caps between the two Punto's. Just be wary if you then use the 1.2 for a work commute or something as it may then have similar issues, possibly worse even. So might be a weekend thing.

If that seems to fix the problem then a new fuel cap should do the trick.

The theory here being, I am pretty sure that most of that era of fuel cap have a vent valve that may be the cause of the issue. Otherwise I can fire up my workshop and parts manual and have a look to see if there are any other actual tank vents.

Will be interesting to see how you get on. ideally a few cold starts with no cap would be good to really prove the theory.

Have fun!

mvr, Feb 14, 5:21am
OK will give that a go and let you know!
Handy that we have two lol ! ;-)

It's not that it wont start at all, it just doesnt like catching first turn of the key.
So something isnt getting through properly, and logic says it must be something to do with fuel or air or both.
Once it catches properly you hear the variator kick in (or something whatever it is in there) and the revs go up and down slightly, and then its totally fine.

mechnificent, Feb 14, 6:38am
This thing is emission controlled surely ?

It will have a carbon canister won't it and controlled venting. I doubt the cap will be vented.

I'd also suggest that if it is blocked, first start is hardly going to be when it will cause a problem.

Jazz is the resident expert on all things euro so I'll watch but if you want some other ideas call out. It gets too confusing if everyone is suggesting things to try all at once. especially if they are just guesses and you'll end up on anything but a logical progression.

thejazzpianoma, Feb 14, 7:37am
That may well be the case. However a lot of Fiat petrol caps of the era do at least appear to have vent holes and what looks like a valve in them, so given it costs no money and very little time to rule it out, I figure why not be sure.

mechnificent, Feb 14, 7:43am
Go for it Jazz.

It's not looking or being very systematic though.

Perhaps looking on a fiat forum will find the right answer.

mvr, Feb 15, 3:50am
Ive searched a lot of Fiat forums, but seems it's hard to find people with specific knowledge of the HGT Punto's,
loads of info on the normal ones but not so much on these.

It's not an overly urgent problem, the car runs fine and the not starting first pop isnt getting any worse,
I was just interested to see what people's ideas were on what might be causing it.
I appreciate all input :-)

gsimpson, Feb 15, 6:00am
I would suggest downloading multiecuscan (free) and running in simulation mode to see if does what you want. This doesn't require connecting to a car. Connect to simulated engine computer and look under parameters.
MES and cable will save you a lot of time and guesswork.

mvr, Feb 15, 11:14pm
Yep that multiecuscan thingee me bob certainly looks like the way to go! Thanks guys! :-)

thejazzpianoma, Feb 19, 4:18am
Any update on this mvr?
No panic if you haven't had a chance to play with it yet, I was just curious to see how you were getting on.

mvr, Feb 23, 4:53am
Sorry havent had a chance yet Jazz . and my Silver 1.2 threw it's spark plugs/leads today . driving along in suburbia and it suddenly starts to shudder and shake really badly, engine warning light flashing at me, loss of power etc etc (but temp is OK). Get the AA to tow me to mechanic, diagnostic shows cylinder #3, check the plugs, yep old and need replacing, drive off back to work and 10mins later same thing, back to the mechanic, now the other cylinders are showing on scan, changes the coil pack, nope doesnt fix it, changes the leads, yep done. I thought the blimmin engine was going to explode the way it was behaving! Oh and this car (the Silver 1.2) just needed 2 new tyres, a rear tail light (faded), a new wiper arm and a split CV boot to get it's WOF just last week . nothing like dropping a grand in repairs on a car in a week

mechnificent, Feb 23, 5:21am
So I gotta ask. did they charge you for the coil ?