Technical HELP! Engine cutting out/not starting, Dealer stumped :(

[turpz]

Having major problems with sister's 1.2 grande and the Fiat dealer are being no help whatsoever, so I thought I'd see if anyone here can shed any light.

Short story is, engine cutting out, or not starting at all. Other electrics are fine, lights/stereo etc, and so far the dealer has said alternator is fine, replaced battery and some spark plugs, and think it's "something electrical".

Longer version, the car wouldn't start last weekend. Jump started it and it drove fine for a good couple of hours until stalling after an emergency stop The engine wouldn't start for around 10 mins, then carried on driving. Then oil warning light & steering light came on, oil temp shot up and engine cut out & wouldn't start again.

Got towed to dealer who said alternator was fine, but battery was weak, so had new one fitted. Driving it after that, it kept juddering like about to stall, oil light/gauge flashed up again, as well as engine warning light, did this about 6 times in 40 mins, so back to garage.

They tried diagnostics, said something was shorting/spiking, but couldn't tell what or where, possibly a fault in the ignition. They changed some spark plugs and sent us on our way. It's been left over the weekend, and engine won't start again. :bang:

Sorry for the EPIC post, but the dealer doesn't seem to have a clue, yet is happy to keep charging for work that may or may not fix it. They've agreed to have another quick look for free tomorrow, so any suggestions/pointers, can't keep paying £90p/h for them to guess at stuff

 

[D4nny8oy]

When it won't start, does it do anything (ie, does it turn over on the starter)? When the problem occurs, you say everything else unrelated to the engine works fine?

Sounds like a possible issue with the main engine/gearbox to chassis earth.

By the way- it won't be an oil temp gauge/light- it's coolant/water temp.

 

[Austin Mini]

So you jump started the engine and all was well until you stalled it. Sounds to me like a bad earth somewhere. Have a look at the braided earth strap from engine to bodywork this may need replacing.

 

[turpz]

D4nny8oy - When we turn the key the lights on the dash light up but there is no engine sound at all, complete silence. However, just tried again, held the key for a few seconds after turning and heard a sort of whining noise, turned it off and straight on again and it started (after a couple of stutters). Another mechanic mentioned the earth strap from the battery which the garage said they'd checked... is this the same earth you mean? Is it something obvious I would be able to see if I knew where to look? Thanks Austin Mini, will mention to the garage.

 

[Andy Monty]

You got any jump leads?

if so clamp one to the negative battery post and the other end of it to the engine block (bit of clean shiny metal)

does the car start ok then?


cable runs from quick release battery terminal down to the front chassis leg then onwards to the top of the gear box...

https://www.fiatforum.com/grande-punto-guides/169204-grande-punto-engine-bay-earthing-points.html

https://www.fiatforum.com/gallery/data/500/medium/DSCF09041.JPG

https://www.fiatforum.com/gallery/data/500/medium/gear_box_earth.JPG


often this cable breaks internally and can cause high resistance leading to starting trouble and strange error messages

 

[D4nny8oy]

D4nny8oy - When we turn the key the lights on the dash light up but there is no engine sound at all, complete silence. However, just tried again, held the key for a few seconds after turning and heard a sort of whining noise, turned it off and straight on again and it started (after a couple of stutters). Another mechanic mentioned the earth strap from the battery which the garage said they'd checked... is this the same earth you mean? Is it something obvious I would be able to see if I knew where to look? Thanks Austin Mini, will mention to the garage.

There'll be a main earth cable from the battery negative terminal to the chassis just under the battery tray, then one from that point onto the gearbox.

Sometimes these get left loose when the clutch is replaced (or any other reason for the gearbox to be off), and sometimes they corrode/break internally and cause intermittant issues like what you're having. A continuity test is often no good as the fault may only happen when under load.

 

[turpz]

Thanks both - don't have jump cables to try but will pass on the words of wisdom to the garage in the morning. Did mention this before on advice of someone else but who knows if they bothered to check.

 

[turpz]

Update, dealer now saying they think it could the ECU, won't know more until tomorrow. (Green Flag man checked earthing etc before he took it, so seems not to be the earth strap.)

They're checking the wiring "just to make sure", spouted off vague bits about signals etc, and said could be looking at £300-700 for a new ECU.

If that is what it is, how does that price sound, and why such the wide price range? Surely these sort of things have a set cost? Feeling very frustrated right now, feels a bit like they're making it up as they go along.

 

[Andy Monty]

Update, dealer now saying they think it could the ECU, won't know more until tomorrow. (Green Flag man checked earthing etc before he took it, so seems not to be the earth strap.)

They're checking the wiring "just to make sure", spouted off vague bits about signals etc, and said could be looking at £300-700 for a new ECU.

If that is what it is, how does that price sound, and why such the wide price range? Surely these sort of things have a set cost? Feeling very frustrated right now, feels a bit like they're making it up as they go along.

Dont go swapping the ECU till you have exhausted all other avenues

How did the green flag man check the earths as danny said above. it can be hard to test for...... Have you tried the battery and jump lead test? if not i suggest you do... failing that get a new earth strap and try it for what it will cost over a new ECU
?
How have the tested the "signals" without a fiat computer system?

also check the little earth cable to the ecu is clean

https://www.fiatforum.com/attachment.php?attachmentid=78269&d=1274535116

*small black wire with ring crimp which is disconnected in lower left of pic

 

[turpz]

Don't worry, not planning on doing anything rash - the dealer has the car and has been looking at it for free all today, they've been told not to do anything chargeable until they know exactly what the problem is & we give the go ahead.

I only assumed the green flag man had tested it because after I mentioned it he got some sort of reader/meter machine, and was touching red & black wires to various parts of the battery, engine and bodywork, thought that was he was testing. He did a lot of fiddling with fuses, wires and jump leads, but my knowledge under the bonnet is pretty much nil, so couldn't say exactly what he checked, but know he didn't have any ideas either.

As I said, the car's back at the garage now, so had no chance to do the battery/jump lead test etc, but that's where they've done the testing with the Fiat computer system. Just waiting to hear from them tomorrow, whether it's wiring from ECU, ECU itself, or something totally new

 

[jackstearn90]

ive been having the exact same problems, at first it wasnt startin becoz it had immobilized itself, and was due to a lose connection to the body control computer, but a week later its happening again:bang:, the temp gauge shoots up and down, engine managment light flickers on and off, immobilizer comes on and off, engine starts then cuts out, if i drive it itl lose power and the steering light comes on, had about nine mechanics look at it and theyve all been stumped

 

[Mal126]

Don't worry, not planning on doing anything rash - the dealer has the car and has been looking at it for free all today, they've been told not to do anything chargeable until they know exactly what the problem is & we give the go ahead.

I only assumed the green flag man had tested it because after I mentioned it he got some sort of reader/meter machine, and was touching red & black wires to various parts of the battery, engine and bodywork, thought that was he was testing. He did a lot of fiddling with fuses, wires and jump leads, but my knowledge under the bonnet is pretty much nil, so couldn't say exactly what he checked, but know he didn't have any ideas either.

As I said, the car's back at the garage now, so had no chance to do the battery/jump lead test etc, but that's where they've done the testing with the Fiat computer system. Just waiting to hear from them tomorrow, whether it's wiring from ECU, ECU itself, or something totally new

Sounds like ignition switch to me !!

 

[D4nny8oy]

Sounds like ignition switch to me !!

Possibly, but it wouldn't explain how everything else is working except the engine/starter.

 

[T14086]

the dealer doesn't seem to have a clue, yet is happy to keep charging for work that may or may not fix it. They've agreed to have another quick look for free tomorrow, so any suggestions/pointers, can't keep paying £90p/h for them to guess at stuff

After a respectable amount of time (IMO 2-3 hours) if nothing is showing up then dealer should be contacting technical for help. The only reason why you are continually getting charged is because the way dealerships are set up.

I would request the garage ask for a field engineer be sent out and if not get the car taken away from the garage and taken to a good independent garage.

 

[turpz]

Thanks everyone for your help, final update - my sister has her car back in working order.

After nearly 2 weeks, 3 trips to the dealer, and many many days of chasing the mechanic via phone ("he's not looked at it yet", "he's looking at it now", "we were going to ring but lost your number" etc etc ) they found...

A broken wire.

So on the positive side, it turned out to be an easy fix (& they even waived the £45 charge as a goodwill gesture). Shame it took nearly a fortnight and £400 to get there!

The last visit to be fair, they've charged nothing, no labour etc. But if, as they made out, they've been working on it for 4 days straight you'd think they'd have spotted the problem sooner.

Thanks again guys, nice to know there's decent advice to be found out there when in need! :worship:

 

[jackstearn90]

What wire was it??

 

[Andy Monty]

My money is on earth wire from battery

 

[turpz]

The note they gave sis with the car says they carried out examine tests, found supply to engine ECU low. Trace fault to live between pin 1 of connector A and pin 28 of fuse box, found high resistance in wiring loom.