Hi everybody, first post so hope this is the right place.

I've scanned the forums and found a few references to this problem but not the symptoms I'm getting.

I've got a 2003 Stilo petrol 1.6. About a week ago I started getting the EOBD, "Engine fault plus spanner" light come on and flashing for a bout 3-4 seconds.
This ONLY happens when I am doing over 75 (know its illegal but )

If I drop the speed back to 70-75 it stops, this is entirely repeatable, over 75 light comes on under 75 light goes off.

By the way when the light is on the car runs normally, no judder, no miss firing seems to be fine ?????

Took it into Fiat who did a diagnostic test on it and said there was a fault with one of the coils, they replaced this plus the spark plug for only £145 .

Guess what no difference. The only thing I have had done recently is to have all the timing belts, fan belt etc replaced as they were whining.

I dont really want to get into a game of "guess the part" where Fiat guess a bit, I pay for it and round we go as my bank account empties. Has anyone else had this, or have an idea what it is.

I drive about 600 miles a week so dont really want to be picking up bits of my engine off the M56 if it is a potential catastrophe waiting to happen

Thanks in advance to anyone who can help or scare me

First of all, if a coil goes you will know about it. I doubt you would actually reach 70 mph, and if you did it would take you until about next week.

The engine has one coil per cylinder and it is very common for them to go on the older cars. Mine has had all 4 replaced over the time we've had it. They cost about £40 over the counter at your local stealer and take about 12 minutes to change from opening to closing the bonnet. So your cost of £145 for a coil and a plug sounds high to me (the coil would have to come out to change the plug anyway).

Anyway, back to your topic. Is it truly vehicle speed related, or is it engine speed related? Does the MIL come on if you are in say 3rd gear at the same speed? (would a 1.6 do 75 in 3rd ???) or even 4th gear?? Or accelerating through the gears to get to the same engine speed as when the light comes on???

Unfortunately, the light has a single warning indicator function, reporting probably several hundred possible reasons ands needs to be decoded by diagnostic software. I would go to an independant garage with the necessary "examiner" kit and get them to diagnose the fault properly if possible. You could then hopefully solve the problem in the most efficient (and cost) method. Fiat will rob you blind for this service. IMO

If it otherwise operates OK I would doubt that changing the belt has had any affect.

Thanks for the reply Stilo ste

Must admit I hate taking it to the Fiat dealer coz I know i will be ripped off but I naively assumed that they might know more about the fault, have seen it before and would know how to fix it (I was wrong). Said they could do it there and then, should have asked the price first!!

Also all garages seem to be skilled at ripping you off anyway

In terms of whether its a speed thing or engine revs I'll check that out on the way home tonight. I should be able to do 75 in 4th 3rd is another matter.

Could it be duff fuel, I had just filled up before it started?

Stilo_ste said:

would a 1.6 do 75 in 3rd ??? or even 4th gear??

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Yes. And yes.

(75 mph equals 125 km/h, and I'm pretty sure I've been there some times...)

When was the last oil change? Just to mention the importance of good oil and new filter.

M.

Had the oil changed at the same time as the belts about three weeks ago and the filter

Does this happen when revving the engine?

It could be that the timing is slightly out, as the engine node will detect this by referencing the readings from the sensors at the cam and the crank. I was told by a FIAT DET that there is a procedure to align these readings - you have to rev the car over 4000rpm (I think) a few times and the Examiner will check it out.

Also, FIAT can plug in the Examiner and then take the car out - it's a live diagnostic. They can then find out whats wrong when the fault code is transmitted.

rroope said:

Does this happen when revving the engine?

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Hi Rich,

Havent tried this yet, it doesnt happen at higher revs in lower gears when I'm accelerating etc but what with having had the timing belts changed it might be possible,

I'll check this out sitting in the drive, It makes sense what with higher speeds == higher revs for a longer period of time esp when I'm on the motorway.

I'll mention taking the diagnostic tool out on a test drive to Fiat although they did say it was technically not legal for them to test it out over 70

If I can get it to happen at high revs that actually would be a bonus in getting it sorted quicker and hopefully before I need a new mortgage.

snap, i have exactly the same fault, only happens on the motorway at higher speeds, i to recently had the cam belt replaced and never happened prior to this, so i reckon it has to be connected in some way, cars running fine otherwise.

Hi BobCat hurrah its not just me then. :worship:

I'm seeing Fiat again next week (I'm a masochist) and will mention your post.

Do you have access to a EOBD reader, such as the ELM scanner? There are programs out that will do live data and diagnostics on the engine system.

rroope said:

It could be that the timing is slightly out.

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that wudda been my guess. I'd have them check it. did the dealer change the timing belt? if its out and yet they've charged you for a part you didnt even need, they might sort you something out

Could be your lambda sensor.

I had a similar problem on my last car.

When I was on the motorway doing about 90 at 4000 rpm, the engine management light would come on, then if i eased off until the revs got down to 3500 rpm (about 80/85 i think) the light would turn off. Completely repeatable like yours is.

Did a diagnostic (with a paperclip ) turned out the lambda was at fault. Changed it and and no more engine management light above 4000 rpm.

Thanks for the posts chaps.

Got some suggestions to pass to the dealer, maybe they will give me a discount for you lot doing their job

Nope the Dealer didnt change the belts it was an independent garage.

Noticed this morning that early on in my 45 mile journey (1st 15 miles) I can do 85 no problems, as the journey went on light started kicking in at 75+

As I've had the belts changed recently timing seems like a number one contender although your symptoms Juelz sound exactly the same. How does the paperclip work

Havent got access to a Diagnostic scanner I'm afraid, where would you get one?

Meady said:

How does the paperclip work

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I did it on a mk3 astra, basically worked by sticking a opened out paperclip in the diagnostic socket and counting how many time the engine management light flashed to get the fault codes.

You won't be able to do this on a stilo though, so it looks like a trip to your local dealer

Most older Vauxhalls flashed out the fault code if you earthed one of the pins in the OBD socket, via the engine warning light.

To behonest, i would have thought that if the timing was out you WOULD notice across the entire rev range, not just at higher rpms.

Hmmmmm, confused now

It does seem more than a coincidence that bobcat has got the same problem as me after having a cam belt replaced. Apart from timing could this have caused anything else?

Is there an ECU learning procedure that needs to be gone thru by the mechanic after changing timing belts???

I see your point though Stilo ste but not being that mechanically minded I'm a bit of a lamb to slaughter in terms of getting it repaired.

Its weird that there is no discernable loss of power, acceleration and the car "appears" to be running smoothly.

How sensitive are the sensors, are they measuring exhaust emissions?

Seems to me if it was a gross error occurring I would notice some performance/running change to the car as it was occurring. But its not random like a faulty connection, the conditions it occurs under are always the same.

Are there any generic garages you would recommend Halfords? or will I just get ripped off by them as well?

For something to do have you tried adjusting the Speed Limit Warning in 'My Car' (you never know )

Why not Prayer hasnt worked :bang:

Any idea what fault codes the garage found when you took it in?
I would have thought that you'd be getting some fault codes stored if it's a regular occurance so you could save yourself a lot of soul searching by buying a simple EOBD fault code reader and see in what area the fault is occuring. Or, if you're keen, obtain an EOBD interface and check it out on your laptop if you have one. You can have it plugged in and record what's happening at 70mph too. It's a lot of guess work otherwise

Noticed that Halford were selling fault readers for about £25 might get one this weekend and see what it says.

Do you know off hand where the connector for the fault reader is on a Stilo, are they standard connectors?

In terms of the error codes the dealer found I dont know specifically what they were but they said that it indicated a fault with the number 2 ignition coil.
They replaced this and the spark plug but this did bugger all.

Problem is this could just be a fault code as a consequence of a fault earlier on in the sequence of events.

its going in again next Tuesday so I can pay for the mechanics summer hols I'll get them to tell me the specific DTC codes if I havent got a reader working by then.