Seat Ibiza won't start when hot?

[Barking Mat]

Sunday afternoon car problems folks.

My parents 2002, 1.2 3 cylinder seat Ibiza (petrol), won't start occasionally when hot, after a short run to the shops they have to wait up to an hour for it to cool down. It turns over but won't start.

The immobiliser light comes on apparently, the barrel has been changed since this started two years ago, the local garage has checked the ecu and can't find any probs.

Since I've borrowed it its fine.

Its not running particularly smoothly.

I changed the coil packs a couple of years ago.

Checked all connections for corrosion all good.

Checked YouTube and google, some lass had same problem, eventually sent off ecu to be fixed and problem solved.

Anyone any thoughts please?

 

[the snooper]

Could be a dry joint in the ecu try tapping it when it fails to start

 

[Barking Mat]

If I can get it to play up I will try that, thanks.

 

[migmag]

Have you had it scanned

 

[gaz1]

change your coil pack the seat ibiza had same problem once changed again it runs far better now

also did the same when cold was a swine to start sometimes

this ibiza only has 14,000 on the clock legit mileage for a p reg car

 

[swedge]

Could be the crank sensor as it's heat that kills these

I had a car that would overheat slightly and wouldn't start and it always cane up crank sensor it finally died in the end had to replace the sensor

 

[Barking Mat]

Left car running for 40 mins, up to temperature, fan comes on etc.
Allegedly an auto electrician has checked the ecu and allegedly the immobiliser has been bypassed through the ecu?
The immobiliser light still comes on for 2 secs and then goes off before starting.
Will try a new crank sensor.
Coil packs changed 2 years ago, unlikely all 3 coil packs fail at same time when hot. Car does minimal mi!eage.
Speaking to my father the immobiliser light stays on when it wont start.
Immobiliser is in the ecu I guess?

When left running with bonnet open ecu unit seemed hotter than surrounding metalwork, is that normal?

 

[rtcosic]

Can I be the daft one at the back of the class?

What is an 'immobiliser light'?

Another possible sensor issue - temperature sensor fubar and telling the ecu to try to start an hot engine on the cold start map?

Car does minimal mileage - Italian tune up needed to free sticking valves?

 

[Barking Mat]

Immobiliser light is a warning light rough outline of a car, the rear wheel is a key.
Having spent Sunday trawling the net, this is a problem with seats, best solution seems to be to disconnect the battery and put the wires together, or leave the key in the ignition in 'on' and wait ten minutes for the light to go off.

Immobiliser probably in ecu, sometimes under dashboard, could equally be the transponder aerial?

Such an intermittent fault garages don't normally find it.

There are some people doing daft things on YouTube trying to solve problems with immobilisers.

Anyone with any better ideas please let me know.

I will try the crank position sensor anyway.

 

[tinker jim]

One more vote for crank sensor they can play up when hot high resistance .

 

[rtcosic]

Immobiliser light is a warning light rough outline of a car, the rear wheel is a key.

Thanks. Never noticed that symbol before. Now I'll be on the hunt for it every time I get into a 'new' vehicle.

 

[normspanners]

I did have a similar problem with the lads rag top bmw he went to chester for kfc ( coz its drive through lazy bast...)---- only 8mls when we have one 2mls but you have to get out!! anyway he sat there ( coz of the great british summer) with it idling whilst he ate it then shut the car off and listened to music or phone etc and it would NOT start, no codes------ no problems etc etc, the temp was now in the red coz of latent heat I told him to open the bonnet and let it cool off 20mins then got him to crank it whilst I listened to it and I heard it pick up on one----- he then stopped cranking it so a little word in his shell like and we tried again and it picked up each one after the other so it had to be the fuel had vapour locked in the injection system by cranking it, it eventually sent cold fuel through the system, and you could hear each cylinder get fuel.
he hasnt had an issue since ran perfect after it is VERY unusual to have vapour lock in an injection motor.
????? has the ibefa got returnless injection ie single pipe system?? are there any heat shields missing off exhaust etc ??

 

[Barking Mat]

Thanks for that @normspanners, (and everyone else), I opened the bonnet looking for a dizzy cap! I couldnt tell you about the injection system without having a look, (I'm at work). I stopped playing with petrol cars some years ago.
Ive ordered new sparkplugs, coils, crank sensor and all the filters, will see if that makes a diference?
Still suspect immobiliser issue. Not having a diagnostic thing to plug in doesnt help, and until the problem resurfaces I'm probably to tight to go see a garage. We'll see. Thanks again folks.

 

[Barking Mat]

@normspanners , from memory, all is complete under the bonnet. Its only me and the local garage whos played with it. I'm getting quite good at not breaking things.

 

[normspanners]

you need to find out how it started did it just suddenly start or sort of stutter into life.

 

[Barking Mat]

@normspanners , youve lost me. Just occasionally, when hot, after a short drive it won't start. Problem being its not my car and it seems to work fine. So im sorry I'm a bit lost at the above remark. I don't know how it started, it does, but apparently sometimes it won't.

 

[slim_boy_fat]

Thanks for that @normspanners, (and everyone else), I opened the bonnet looking for a dizzy cap! I couldnt tell you about the injection system without having a look, (I'm at work). I stopped playing with petrol cars some years ago.
Ive ordered new sparkplugs, coils, crank sensor and all the filters, will see if that makes a diference?
Still suspect immobiliser issue. Not having a diagnostic thing to plug in doesnt help, and until the problem resurfaces I'm probably to tight to go see a garage. We'll see. Thanks again folks.

You'd have got a cheap [but adequate] code reader from the 'Bay for less than the cost of that lot.

 

[Barking Mat]

yes @slim_boy_fat I agree, but seeing as they havent had it serviced for 'ahem'..... it needs doing anyway, and won't do any harm, might sort it out and apparently (allegedly), the garage has done this, to no avail, and reading the net, seems to be an ecu problem......But thanks

 

[slim_boy_fat]

but seeing as they havent had it serviced for 'ahem'

In that case, I'm afraid I'd be giving them the famous 'Gallic shrug' - self inflicted problems get little sympathy here, I'm afraid...... https://www.thelocal.fr/galleries/culture/strange-french-gestures-explained-/8 Although I DO appreciate that no amount of regular servicing would prevent an ECU problem.

I refer you to another current thread about stupid people.....

 

[johnny7]

Some years ago I had a Vauxhall Carlton, Loved it too!!

Anyhow, That was the same, Would start from cold but no way when warm, I recalled a mate at work having the same problem and asking one of the auto electricians, He was told that the field windings in the starter were kaput! The insulation is nothing more than sprayed on lacquer and what happens whilst hot is that the lacquer melted and the windings were shorted on themselves but once cool, It formed the barrier that it was supposed to!

I remembered that from years before, A trip to the scrappy saw me get home with a good s/h replacement, Fitting was a git as the steering box was totally in the way!

Managed it though and was amazed at how much more speedily the thing turned over!!

Never had another problem with it until I realised the mot had had run out some months later, No time to get it ready for the test so I scrapped it and bought another


John