Hi Peeps..........

Urgent help needed................

My car is a 2001 Punto 1.2 Go 8V - I have owned it since new in 2001 and it has done me 130,000 virtual trouble free miles - until now.

3 or 4 months ago, its started juddering (especially on engine overrun) - new leads and plugs. All sorted - then it started again and the dreaded engine management light came on coupla weeks ago.
Looked at plugs and they were fouled and sooty as if running too rich - all 4 plugs.

New Lambda sensor fitted and seemed to sort it - then I noticed that it developed a flat spot between 2-3000 revs and the mpg figures going down from low 50s on a run to mid 30s............
Injector cleaner - 1/4 tank of petrol and full bottle - seemed to improve it a bit but not completely.
Now left with a flat spot and high fuel consumption. My garage suspects that the Cat has gone/blocked but quoted £600/650 to fix which then makes it questionable as to whether to do or not.........ironically enough, my emissions are still fine.
Engine management light coming on at strange times - ie tickover or under stress - no rhyme or reason.

Anyone heard of this before? Any bodgit suggestions?

Normally run supermarket petrol before anyone asks - oil consumption is about half a dipstick (ie between min and max) every 3 months whilst doing about 4/5000 miles.

tricky one....done all the things I would have done thus far...might be worth rebooting the ECU by disconnecting the battery overnight....otherwise probably one of the sensors so will need a code reader...
good luck

tinytim said:

tricky one....done all the things I would have done thus far...might be worth rebooting the ECU by disconnecting the battery overnight....otherwise probably one of the sensors so will need a code reader...
good luck

Click to expand...

Interesting - garage today cleaned up the mapping sensor and also was a bit gunky around the carb butterfly (this was done last week) - another garage suggested I rebooted the ecu by disconnecting it, starting the car and bounce the engine off the rev limiter to "re-learn" the settings again..........sounds like a "bang" waiting to happen lol

The MAF sensor can cause the rich running problems. It measures air flow by the cooling effect on a hot wire. When the wire is dirty it miss-reads the airflow.

Also check the readings from the ECU temperature sender. Basically you are looking for a smooth decrease in resistance as the engine gets warmer.

If the ECU is being told the engine is colder than it really is, it will up the fuel going in.

Cheers

SPD