gavinvr6 0 Posted September 9, 2009 Report Share Posted September 9, 2009 on my way to no-rice tonight i pulled away from some traffic lights perfectly sensible and the car started running like a friggin pig, and seemed to be mis-firing on a cylinder. i pulled over and found #3 plug lead loose so i pulled it off and made sure the plug was ok, re-fitted the lead and tried pulling off, only for it to run bad again. its a lot worse under load than just revving. so i called the rac out. he tried similar things after i told him what happened and what i done then i got a nasty rattling noise come from the engine, sounded like some thing was loose inside the engine. it was a similar sound to maybe a heat sheild rattling badly. it wasnt chain slap coz that sounds different. and not a bottom end banging/knocking, with the rac blokes head still in the engine bay i jumped through the window (literally) and turned it off, when i got back to the engine bay the rac bloke simply said "small end". he seemed to think the small end bearings had given up. prior to the hassle at the lights i went up a very steep hill it was over4 a 1 in 3. i think the sign said 38%, and when i got to the top it mis-fired, but then was running ok. so i got on the motor way and it started holding back under acceleration, then to he lights and it went to pot.sorry to sound desperate but please please please can anyone shed some light i need my car back on the road asap. also is it worth me pulling the sump to check the bearings or for bits of metal coz it really sounded like something rattling round in the engineapologies for the essay but i know its better to give as much info as possible than for you guys to need to ask questions. and needless to say im not happy coz i missed no-bloody-rice tonight and cant get back there for a couple of months now.if anyone was south on a3 from m25 between 7 and 8:30 then yep that was me in the layby looking like he was gunna cry lol Link to post Share on other sites
gavinvr6 0 Posted September 15, 2009 Author Report Share Posted September 15, 2009 *****UPDATE*****after pulling the plug leads and arcing them to engine parts i found the rear 3 leads to give a nice loud popping noise and a chunky bright spark but the front 3 a quiet weak arse clicking noise and a barely visible spark. could this be the coil pack breaking down?any help would be great as i cant afford to replace the coil pack only to find out its not that Link to post Share on other sites
Roots 4 Posted September 15, 2009 Report Share Posted September 15, 2009 could be the leads arching, which means there's a beak in the lead somewhere Link to post Share on other sites
Rikki 2 Posted September 15, 2009 Report Share Posted September 15, 2009 Think it could be coil pack mate....! Link to post Share on other sites
daleyboyVR6 6 Posted September 15, 2009 Report Share Posted September 15, 2009 When my coilpack went i ,like you, i thought something was badly wrong with the engine...........if you havent or dont know when the coilpack was last changed then its almost a certainty they are quite often the weak link with these cars...................... ^o) Link to post Share on other sites
gavinvr6 0 Posted September 17, 2009 Author Report Share Posted September 17, 2009 i personally changed the coil pack 2 years ago for a generic one costing £110 after showing up a supercharged jag. ok yeah it was an expensive lesson to teach him but it had to be done. i have changed the front 3 leads for ones i know to be good so cant be them arcing.just trying to eliminate as many things as poss before i go for the coil pack. i've had a quick look over all the wire's leading to the couil pack from the loom and they as well as the plug seem in good condition. is there like something these wires come from that plug into the coil pack like a pre amp thing or something to tell em when to spark? but im guessing since they are spoarking at the correct time its something to do with the output not inpur of the coil pack Link to post Share on other sites
gavinvr6 0 Posted September 20, 2009 Author Report Share Posted September 20, 2009 if the coil pack runs in 3 banks of 2 why would my front 3 leads appear to be giving a weaker spark?as i said i arc'd the leads against the same bracket each time and the rears gave a good loud pop and a bright spark yet the front 3 were a faint click and a faint spark. ive replaced leads and plugs but have yet to take the car out on a good hard run through fear of breaking down again. if the coil pack was breaking down wouldnt it cause probs for an even number of cylinders. 1 and 2 or 3 and 4 or 5 and 6 not 2 4 and 6.i really need this fixed as i gotta drive from south coast to south london saturday and sunday next week for work and to see my kids Link to post Share on other sites
gavinvr6 0 Posted September 23, 2009 Author Report Share Posted September 23, 2009 has anyone ever experianced a voltage drop on the signal from the ecu to the icm thats fitted to the coil pack, was thinking maybe a dodgy wire meaning as the signal alternate's from coil to coil its only telling the rear one's to spark correctly and the front are getting a weak signal meaning not much to boost up to spark strength if that makes sense. or am i way off the mark in thinking the 5volt signal from the ecu is amplified by the icm (ignition control module, thats mounted on top of the coilpack) then coils to generate the spark.i got a new coil pack delivered today so im hoping that will sort it out,if not are there any more idea's? Link to post Share on other sites
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