Technical Chokeing/Backfiring

[metheor]

Hi, my fiat Brava 1.6 automatic petrol started to act funny recently. Usually it runs fine but now and then it starts to slow down when I try to accelerate, it looks like it's choking but when I push the throttle pedal to the metal it revs up and goes crazy. Sometimes it's being followed by some noise from the exhaust, likee it's trying to spit something out. After some time it starts to run normally. There is a lot of dodgy smell coming out from the exhaust but I expect it to be catalyst.

I've checked posts and found something about refuelling but it doesn't seem to fit exactly to my problem.

There are no warning lights on the dash.

Any ideas?


Cheers
M

 

[mikeyprg]

without seeing the car well have to do this by process of elimination.
for starters does the smell have a kind of eggy smell ?

 

[fiat37]

Try cleaning throttle body first, you will find guide on this page at Stilo guides. Measure resistance of ignition coil and cables. Change spark-plugs if you didn't change them more than 2 years. Try cleaning big black connector(wiring for FUSE box) just behind the battery. Check TPS connector, too.

 

[metheor]

Hm now you've said it it seems that I could smell something eggy. Anyway I think I've killed my catalyst because it seems I was running on 3 cylinders. I've chcecked the leads and one sems to be faulty. Can't check the spark plugs yet.... a spanner I've got is too short...

 

[mikeyprg]

ahh yeah thats the smell of petrol eating the catalyst :yuck: but atleast you have found the problem