Alfa Romeo Forum banner

1 - 10 of 10 Posts

·
Registered
Joined
·
109 Posts
Discussion Starter #1
my light is on and flashes every now and then. When i bought it 2 days ago the lady said it was on, and the computer said misfiring cylinder 2. She changed all plugs and noticed lead 2 was loose. Everything was then fine

Anyway today light is on and flashing and it is hesitant like its running on 3 cylindes. Is there a way the car can tell me whats wrong??
 

·
Registered
Joined
·
2,077 Posts
my light is on and flashes every now and then. When i bought it 2 days ago the lady said it was on, and the computer said misfiring cylinder 2. She changed all plugs and noticed lead 2 was loose. Everything was then fine

Anyway today light is on and flashing and it is hesitant like its running on 3 cylindes. Is there a way the car can tell me whats wrong??
Cars usually tell you there is something wrong by stopping just when its not convenient, welcome to alfa ownership:), seriously though, find your nearest specialist (not dealer) and get it checked out, never mess about when the engine management light comes on.
 

·
Registered
Joined
·
109 Posts
Discussion Starter #3
update

when i pull off the 4 main plug caps (they dont come all the way off) all but the 2nd on the left has sparks jumping

when i pull off the other end that joins the cylinders they jump like mad, but thee 2nd on only occasionally and in certain positions

Dodgy lead??
 

·
Registered
Joined
·
170 Posts
Hi Mozza, try testing the coil packs, sounds like one could be knackered and missfiring on that cylinder.
First try swapping the suspect one over with another, see if this moves the misfire to that cylinder, if it does, try testing each pack.
See here for a guide.
Ignition Coils

Basicly, you're checking the resistence of each coil and compere them to each over, someone on here may even know what the reading should be, but a good guide would be, 3 all reading similar, 1 way out, is'll point to that coil as having a problem.
 

·
Registered
Joined
·
109 Posts
Discussion Starter #5
Hi Mozza, try testing the coil packs, sounds like one could be knackered and missfiring on that cylinder.
First try swapping the suspect one over with another, see if this moves the misfire to that cylinder, if it does, try testing each pack.
See here for a guide.
Ignition Coils

Basicly, you're checking the resistence of each coil and compere them to each over, someone on here may even know what the reading should be, but a good guide would be, 3 all reading similar, 1 way out, is'll point to that coil as having a problem.
cheers, i will swap them tomorrow and see if any difference with that cylinder. I dont have the correct tools to get them off so cant do tonight. Im pretty sure its a lead
 

·
Registered
Joined
·
170 Posts
http://www.alfaowner.com/Forum/alfa-147-156-and-gt/198112-how-to-test-a-coil-pack.html

Have a read of this, all you need is a cheap multimeter.

Is it misfiring all the time? does it run the same with that particular suspect coil disconnected? ie. running on 3 pots all the time, coil connected or disconnected?
Have a look at swapping the suspect lead over first, I'm not sure if they just pull out from the coil or unscrew, if you can get hold of a meter, you can check the resistance of these as well, they all should read the same.

Also check the plug cap and plug it's self, a cracked plug will misfire, has it a screw on nipple on the top of the plug, is it tight? Does the cap fit tightly? Is the lead fitted to the coil and cap tightly?

Try looking at things with a bit of logic, discount the easy things one by one, then try and test and narrow down the others.
So swapping the leads only may move the misfire, it's the lead, swapping the coils may move the misfire, it's a coil. If no matter what you swap and the misfire stays, your problem is else where.
 

·
Registered
Joined
·
109 Posts
Discussion Starter #7
it runs fine at idle, just under acceleration its hesitant. Cant change lead without taking the coil pack off as the cover that goes over the plug doesnt come out as the pack is in the way. I dont have a meter but trial and error should tell
 

·
Registered
Joined
·
109 Posts
Discussion Starter #10
all working this morning. I think the lead is breaking down, the lady who owned it before me said the lead had actually come off before and it doesnt seem as solid as the others
 
1 - 10 of 10 Posts
Top