1800rpm

[Deckchair]

Hi
Is there anyone with any ideas before I go for broke and start changing expensive items. I have an uggggg at 1800rpm. That's it. The car hesitates at exactly 1800rpm every time.

It's a 1999 1.2 Bravo 80SX. Has 70K miles and it's done it since I bought it at 6K miles.

Plugs and leads make no difference, niether new air filter. Car is brill in everything else. starts great and goes like hell for a 1.2. Fuel types I've used all sorts and from different countries with no difference in the ugggggh. I can live with it but it makes my neck ache at times.

I've reset the ECU and it seemed a little better for a while but then came back pretty soon. It's really yuck if I drive straight off from cold so I always let it idle for 5mins before using it from cold.

I'm thinking fuel/air tuning but is it air flow sensor? lambda? what could it be? No warning lights of course as one would expect from Fiat.

All pooled thoughts gratefull recieved

 

[Daz155HGT]

How long did you have your battery off to reset your ECU?

I had mine off the first time for 3 hrs, it got slightly better, but the second time i had the battery off for about 12-13 hrs, and only then did it fix the problem

Good luck

Daz

 

[Hlx99]

Re: Re: 1800rpm

Daz if i get the induction kit for my Hlx i can leave the battery off for 12hrs at work, will this reset the ECU ? and will it be ok, keep getting conflicting info, cheers

 

[Deckchair]

Re: Re: Re: 1800rpm

Tbanks Daz
I followed your advice and disconnected the battery overnight for,just like you, I had previously disconnected it for a few hours to reset the ECU and there was a noticeable difference so I guessed the ECU had been reset.

After disconnecting this time completely overnight the first drive this morning was very much better and I thought "Wow, this is it!" but now on the 4th drive today it's deteriorating again back to where it was with flat spot at 1800 rpm.

Am I losing settings when I switch engine off do you think?

 

[Tom]

Re: Re: Re: Re: 1800rpm

Hmm.. its an odd one. I'd try the lambda. Something is causing the ECU to change its settings and mess it up. There is not much else that changes the settings.

www.cats-direct.com universal 4 wire £25+vat.
Also fit a new air filter.

Try and leave the battery off for 24hrs when you change the lambda.

 

[Rab]

Re: Re: Re: Re: Re: 1800rpm

When you disconect the battery does this not lose all the code settings like the radio and do you have to use the red key to re-start?

Rab.

 

[Daz155HGT]

Re: Re: Re: Re: Re: Re: 1800rpm

I had my battery off for about 12 hrs Rab, and didnt need the Red-key.

Nice finally meeting you at Notts.

Daz

 

[Deckchair]

Re: Re: Re: Re: Re: Re: Re: 1800rpm

Thanks for reply Tom
Are lambdas as cheap as that? I'm surprised. The last quote was over £100 so I'll check out your helpful link and get one in straightaway. The air filter is less than 5k so that's OK.

To Rab
yes you will lose your radio settings if you disconnect the battery so turn your radio select onto CODE from SAFE if you haven't the radio code to hand.
Otherwise no you won't need the red key at all.

 

[Rab]

Re: Re: Re: Re: Re: Re: Re: Re: 1800rpm

How do you turn the radio from CODE to SAFE??
I think i have the code but wouldn't mind knowing anyway.
Cheers.

Rab.

 

[Deckchair]

Re: Re: Re: Re: Re: Re: Re: Re: Re: 1800rpm

It's pretty long winded and I think it's already been described further back in the posts. You use Expert mode and get to SAFE then enter the radio code and it will return to CODE. Look in the car manual for the full description.