Could well be the ECU . random misfire. Try swapping the leads to the coils over after having determined which cylinders are misfiring. (infra red thermometer maybe). If the cylinders dont change itll be that horrible pesky micro ECU . They can be repaired whichis one hell of a lot cheaper than getting a new one. Lots of posts here and something in either the guides or faqs.
its a generic code change plugs and leads before anything else
Had a misfire recently. No 1 plug had lost half its insulator into the cylinder. Made a nice mess of the head and piston crown after a few loud clicks on startup. Bosch plugs only 6 months old. Might have been early sign of HG going as well last one was done 26000 miles ago.
For me this was bad leads. Check those and plugs before coil packs and ecu . Also dont leave it to long it cost me a new cat.
Needs the ECU self adaptive parameters resetting and Phonic wheel learn procedure performing. (Dealer job unless the local garages software is upto it) httpwww.fiatforum.compunto23219...und-70mph.html Local garages may be cheaper but if theyd called the local Dealer (or searched on here) theyd have had the answer Im giving you in seconds and saved themselves the time and hassle of replacing working plugs and leads and rechecking the belt.
Originally Posted by WhiteSei D4anny we could do with a guide (or an addition to an existing guide) that explains all these ECU resets learns etc. Can resets be done with a laptop and EOBD lead Can be done with fiatecuscan
Solved Thanks to everyone who posted. After much back and forth between the garage who performed the belt change I contacted a local fiat specialist who flatly refused to accept a phonic wheel learn was required post cam belt change and to prove the point they then stated they would check the timing for free. They did and guess what the timing was out by one tooth. No more ECU flashing light and the
Originally Posted by Entwine Solved Thanks to everyone who posted. After much back and forth between the garage who performed the belt change I contacted a local fiat specialist who flatly refused to accept a phonic wheel learn was required post cam belt change and to prove the point they then stated they would check the timing for free. They did and guess what the timing was out by one tooth. No more
Ok the error is detected because the engine ecu sees a misfire due to the fact that the phonic wheel pattern has changed when the cam belt was changed. The phonic wheel is on the crankshaft pulley and is removed during the cam belt change because it never goes back in EXACTLY the same place the pattern obtained by the rpm sensor does not match the one stored in the ecu and at higher revs a misfire
Thanks Numan that sounds alot more realistic then what the fiat mechanic told us. He said it was down to the new spark plugs fitted not cambelt and he said that the HT leads needed replacing as there werent working properly with the new spark plugs although after saying that he said he was only 90% sure it would fix it which made me begin to doubt him as hes suppose to work with these cars day in day out
Originally Posted by NumanR The car needs to go on examiner and have a reset of the engine ecu carried out and then a phonic wheel learn procedure carried out this will cure the problem. NumanR Hiya Just to clarify is this the same as disconnect the negative terminal for 20 mins to clear the ECU reconnect Having all sorts go wrong with my punto this winter shortly before I changed the wishbones the
doubt the battery is at fault however probs getting a new battery first wud be a good idea the radio cud be a fuse which i think is F39 in the drivers fuse box check that first to see if that cud be the source of the problem and yes finally the 1.2 8v does have a cat and is 60Bhp
Zero the ECU codes then check with the engine cold and again when hot. If the sensor is failing its likely to be worse with the engine hot. Also check the cable connector contacts are clean.
whats the year and engine size Ash
Its a 2002 - 1.2 16v Sporting. Thanks Originally Posted by whitz whats the year and engine size Ash
pull leads out and my guess is one will have a hole in one of the ends that go onto a spark plug that spark can travel to all the other plugs and does some strange things with codes often comes up as multi cylinder miss fire when only one lead has the hole
are the holes easy to spot are we talking about a tear in the rubber thanks Originally Posted by dave pull leads out and my guess is one will have a hole in one of the ends that go onto a spark plug that spark can travel to all the other plugs and does some strange things with codes often comes up as multi cylinder miss fire when only one lead has the hole
Since hunting for more info on the p0300 code within Google I found this link back to my favourite fiat forum website (see below link) httpwww.fiatforum.compunto72577-ecu-fault-p0300.html NumanR returned this interesting post (below) as we underwent a Cam belt change last September (When we purchased it) but never took the car on the motorway until recently. Ok the error is detected because the engine
Originally Posted by mr_craig Hi Guys punto MK2 1.2 8v 2001 Im having a problem with my punto on startup it starts everytime no problem but the idle can is erraticthe problem goes if i rev it to death for 10 seconds. there is no problem with idle or power when driving normally its just at startup if you try and drive it from start without reving you can feel a dramatic loss of power then its fine after