Hi All

I'm brand new to this site, but please help me, I'm at my wit's end! My husband bought a Fiat Bravo 100 SX just 2 weeks ago and it's been back to the garage about 5 times for various problems, nothing too serious except for 1 problem that they tell me is due to the lambda sensor, whatever the heck one of those is!!! He was driving to work about a week ago when the amber light on the dash came on warning of "engine malfunction" so he got to work, did his day's work with the intention of driving it to the garage but it just wouldn't start. It took 20 mins of cranking the engine over before it finally kicked in (he works 25 miles away so couldn't walk home!)

The garage took it, informed us that it was a lambda sensor problem and said they had fixed it, assured us we would have no further trouble. Last night, it happened again - it wouldn't start and the warning light had come on again. Finally, again after about 20 mins it started. Next morning, it started without problem when we came to take it back to the garage. Is this a common problem? Can it be easily rectified? Or is this unusual for the lambda sensor to fail twice in 7 days? I kinda know the guy who sold us the car (£3250 with 12 months warranty so I know it's a good price and am reluctant to let the car go, but we need to be able to rely on the bloody thing!)

Advice anyone please???????

Many thanks
Scrumpy

How did he know that it was the lambda sensor that caused the light? Unless he has the fiat diagnostic toos he would not be able to tell.

1stly - have a try a resetting the ECU to see if that helps. To do this, disconnect the battery overnight (ensuring you have your radio code for the next day).

If this doesnt sort it, get it to fiat to plug the diag tool in to see what it comes up with.

Thanks Wimmy but he did have the diagnostics tool thingummyjiggy. He only told me in was the lambda sensor when he called the next day after he'd done the tests on the car in the service centre. I am just assuming it is the same problem this time as the symptoms are the same.

Is this a serious problem? Is it likely to be a recurring problem?

Thanks in advance
Scrumpy

Hello and welcome .

If it's the sensor itself that's at fault it should usually solve the problem when it's replaced. The sensor measures the exhaust gasses to work out the correct fuel/ air mix in the engine. Therefore if it's not a physical problem with it it could be the processing behind it (in which case the reset might solve this) or some other physical problem, in which case as Wimmy says it's back to the diagnostics.

Hi Guys

Thanks for responding. Firstly (dim woman alert!) what does ECU stand for? Secondly, what will re-setting the ECU achieve?

Many thanks again
Scrumpy

Scrumpy said:

Hi Guys

Thanks for responding. Firstly (dim woman alert!) what does ECU stand for? Secondly, what will re-setting the ECU achieve?

Many thanks again
Scrumpy

Click to expand...

ECU is "Electronic Control Unit" if I'm not mistaken. It's basically a small computer that works out what should work when etc. If it's got it's knickers in a twist then, as with any computer and "reboot" generally sorts it all out. To "reboot" it you need to remove it's power i.e. remove it's connection to the battery.

The ECU reset (or if you like, "reboot") is a common cure-all for electrical gremlins with modern cars. Usually, if something electrical is replaced the ECU doesn't always recognse this and so remains on it's old settings and the problem remains.

Simply disconnect the battery terminals as Wimmy has said and put them back on in the morning. Hopefully this will reset the ECU and all will be well.

Many thanks to you all for taking the trouble to post - it's much appreciated. I will wait to see what the garage say before I disconnect & reboot (yes, that terminology does make more sense to me - thanks )

Cheers again
Scrumpy

Scrumpy said:

(yes, that terminology does make more sense to me - thanks )

Click to expand...

Really? Lambda sensors and the like are all greek to me

mad_colm said:

Really? Lambda sensors and the like are all greek to me

Click to expand...

Buh-dum-dum, tschhh!

The garage have just been on to advise that they've plugged the diagnostic tool kit into the car and it is showing nothing wrong. They've started it, switched it off etc and it's starting everytime without problem. The engine malfunction light is not illuminated and it's running perfectly.

The head honcho is going to drive it home tonight to see if it starts in the morning and he will have the kit with him if it doesn't start.

Question... if it's just a case of a problem within the ECU, would this cause the car not to start? Or is this just indicating a dashboard light problem? I am happy to disconnect the battery overnight to re-set the ECU but, my point is, if that's all it is, that wouldn't make the car not start, would it? or would it??

I am so p*ssed off now with this.

Scrumpy