Stuttering and new coil.....
Discussion
Hi guys,
Wonder if anyone has any ideas?
I've just fitted a new coil to my Chim as part of a general replacement of ignitiony bits and pieces (plugs, Magnecors, shrouds, dissy cap and rotor), the coil was 'OK' before, though was a good few years old and a 'Unipart' Austin Rover model!!)
Its been running fine until two nights ago when I replaced the coil, now I have a terrible 'stutter' below 2500 rpm - it flies after that (and I mean 'flies' - the new coil has made a lot of difference there!)
It only seems to happen on a light or trailing throttle, with the hammer down it picks up fine. It has also taken to 'dying' when pulling off in first, then picking up again in a big whoosh.
It seems to be much worse when cold.
My first thought was a loose connection on the LV leads into the coil, but i've just checked them and they seem OK.
Anyone have any ideas? Has replacing the coil shown up another problem or have I missed something obvious?
Thanks in advance,
Mark
Wonder if anyone has any ideas?
I've just fitted a new coil to my Chim as part of a general replacement of ignitiony bits and pieces (plugs, Magnecors, shrouds, dissy cap and rotor), the coil was 'OK' before, though was a good few years old and a 'Unipart' Austin Rover model!!)
Its been running fine until two nights ago when I replaced the coil, now I have a terrible 'stutter' below 2500 rpm - it flies after that (and I mean 'flies' - the new coil has made a lot of difference there!)
It only seems to happen on a light or trailing throttle, with the hammer down it picks up fine. It has also taken to 'dying' when pulling off in first, then picking up again in a big whoosh.
It seems to be much worse when cold.
My first thought was a loose connection on the LV leads into the coil, but i've just checked them and they seem OK.
Anyone have any ideas? Has replacing the coil shown up another problem or have I missed something obvious?
Thanks in advance,
Mark
sparky11 said:
Arse, that had also occured to me.
Its a 'Flamethrower' from Demon Tweeks - someone mentioned it on a thread the other week.
Anyway of checking the output?
If it was the wrong spec would it run right at high revs? This one is perfect upwards of 2500 rpm.
On Tuesday I fitted a flamethrower coil and magnecor KV85 leads in reference to another PHers thread, and i can honestly say that the car is transformed, torque and pickup have improved no end.
You defo got the 6-8 cylinder one didnt you? it says on the original box label.
>> Edited by shorty123 on Thursday 4th August 10:04
Shorty, yeah - I agree totally! Over 2500 it absolutely takes off. It'll even pull in 3rd from about 1200rpm all the way through to the redline!
(that was a test BTW - I don't drive like that all the time!)
Got no complaints on the performance side, its just pottling along in traffic (my daily commute) thats a pain. I could probably live with it, its not like its kangarooing down the road or anything - I just wanted to know why it had suddenly started now.
Stringbag - Thanks for the offer mate (i'm in Melksham, BTW). I'll have a little fiddle at the weekend and if nothing makes a difference I may just take you up on that!
As an aside, the car came from Bath (Batheaston) so you may well have seen it in the past!
Mark
edited to say - it said 6-8 cylinder on the box (and the coil, I think) is there any way of telling?
>> Edited by sparky11 on Thursday 4th August 10:24
(that was a test BTW - I don't drive like that all the time!)
Got no complaints on the performance side, its just pottling along in traffic (my daily commute) thats a pain. I could probably live with it, its not like its kangarooing down the road or anything - I just wanted to know why it had suddenly started now.
Stringbag - Thanks for the offer mate (i'm in Melksham, BTW). I'll have a little fiddle at the weekend and if nothing makes a difference I may just take you up on that!
As an aside, the car came from Bath (Batheaston) so you may well have seen it in the past!
Mark
edited to say - it said 6-8 cylinder on the box (and the coil, I think) is there any way of telling?
>> Edited by sparky11 on Thursday 4th August 10:24
sparky11 said:
Shorty, yeah - I agree totally! Over 2500 it absolutely takes off. It'll even pull in 3rd from about 1200rpm all the way through to the redline!
good innit!
BTW did you re-gap the plugs, apparently the uprated coil/leads can afford a bigger spark... i havent re-gapped as was waiting to see what the consensus of opinion was.
The only thing i can draw on from experience, is that the dizzy cap can crack under a greater load or higher tension, it maybe worth changing if your still using the original item.
Vehicle Wiring Products in Derbyshire, typically next day delivery, I've always had excellent service and the products are typically good quality too.
The website's pretty naff though www.vehicle-wiring-products.co.uk/ all the info is there just not up to much in apperance.
Regards
Iain
The website's pretty naff though www.vehicle-wiring-products.co.uk/ all the info is there just not up to much in apperance.
Regards
Iain
vinty1 said:
just looked in Demon Tweeks catalogue for this coil as I was thinking of getting one and it states in bold letters 'DESIGNED TO IMPROVE THE PERFORMANCE AND DRIVABILITY OF NON ECU CONTROLED ENGINES' so maybe it is affecting the ECU on your Chim in some way
i got one and have no probs and i think ntel doesnt either.
i still reckon the dizzy cap might need inspection.
just another thought though... whilst fitting the new leads its very easy to dislodge the small vaccuum return pipe that connects to the top of the plenum/ bottom of dizzy... just need to blow on mine and it comes off! if this is the case i should think low rev stability might be affected.
>> Edited by shorty123 on Thursday 4th August 20:55
OK, I managed to find my old coil last night (I hadn't put it in the bin - for some reason i'd chucked it in the back of the garage somewhere.. Thanks for the offer though Karl)
Works fine (well as good as it did before) with the old coil on. On closer inspection and testing last night (my neighbours must love me!) it appears that the Flamethrower does actually miss slightly at higher revs, its just not as noticeable.
Think I might have a duff coil, i'm gonna try and get a replacement this morning.
Dissy cap, rotor and leads have all been replaced - this is the last thing to do!!!
Mark
Works fine (well as good as it did before) with the old coil on. On closer inspection and testing last night (my neighbours must love me!) it appears that the Flamethrower does actually miss slightly at higher revs, its just not as noticeable.
Think I might have a duff coil, i'm gonna try and get a replacement this morning.
Dissy cap, rotor and leads have all been replaced - this is the last thing to do!!!
Mark
I had a coil fail a year or so back and discovered that the ignition system is quite fussy about having the right spec coil, it doesn't seem to be just a matter of matching the LT resistance and voltage. With the 'wrong' coil the engine would start and run easily but was hesitant and didn't feel quite right. Swapping from a good coil the wrong spec to a good coil the right spec transformed it.
Gassing Station | Chimaera | Top of Page | What's New | My Stuff