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stevencos
21-05-2003, 17:52
i found out today that i have a misfire on high boost, i know its not a crack in the block, what else could it be??
Spinza
21-05-2003, 18:02
Is it a misfire or the overboost cutting in??
FAST_FORD
21-05-2003, 18:07
plugs lead coil, gaps of sensors! you name it it could cause it!
plugs i would try first!or make the gaps smaller!

gareth
stevencos
21-05-2003, 22:42
plug gap at the moment is .5mil, do you think it needs to be set up again?
guinnless
22-05-2003, 09:15
How old are the leads?
stevencos
22-05-2003, 17:31
im not sure mate
guinnless
22-05-2003, 18:57
im not sure mate


Looks like time for some new leads then. Dizzy cap and rotor too.
It really does make a difference and misfires are so annoying http://www.turbosport.co.uk/images/smilies/sad.gif
stevencos
22-05-2003, 20:15
is it bad to drive a car with a misfire? how comes it only happends in high boost? how much will new leads, Dizzy cap and rotor be then?
guinnless
23-05-2003, 08:54
Unless it's got a Cat on it it won't cause any damage but why put up with it.
The ignition system is under the most stress under high boost conditions (it's harder for the spark to jump the gap).

Leads, cap and rotor should be had for around £125ish.
stevencos
23-05-2003, 19:48
i checked its got blue motorsport leads on it, is the plug gap allright at .5mil
Andycos
23-05-2003, 20:20
What boost you running Steven, if around 15psi then a plug gap of around .75mm is more suitable i reckon.
I had your sort of problem last year on my cos and it was a plug lead braking down. Changed them to Ford ( blue) Motorsport leads and it was cured http://www.turbosport.co.uk/images/smilies/grin.gif
To see if its the leads or not take it for a blast down the road and get it miss-firing for a bit and then pull in some where safe and whip the plugs out and look to see if one of them is discoloured (sooty). If you do find one not looking to good then swop it for a spare( if you have one) or swop it for one from another cylinder and take it for another blast so you can whip the plugs out again and see if the miss-fire has moved cylinders !!
If it has then its the plug, if not and its still on the same/original cylinder then its either that plug lead or a compression problem possibly http://www.turbosport.co.uk/images/smilies/blush.gif http://www.turbosport.co.uk/images/smilies/grin.gif
Does that all make sense http://www.turbosport.co.uk/images/smilies/crazy.gif http://www.turbosport.co.uk/images/smilies/grin.gif
Well i know what i mean http://www.turbosport.co.uk/images/smilies/laugh.gif
Its a start anyway http://www.turbosport.co.uk/images/smilies/wink.gif http://www.turbosport.co.uk/images/smilies/wink.gif
stevencos
24-05-2003, 00:38
its running 23 psi, ive got the blue motorsport leads
guinnless
24-05-2003, 08:52
Leads should be OK.
0.5mm is too small. Should be 0.65mm.
I sthe dizzy correctly set? Set the engine to TDC (lug to the left of the big groove in the crank pulley) and the rotor should point to a scribe mark in the dizzy body.
stevencos
24-05-2003, 11:38
"Set the engine to TDC (lug to the left of the big groove in the crank pulley) and the rotor should point to a scribe mark in the dizzy body"

mate you completely lost me there!
stevencos
24-05-2003, 11:41
could the gap in the plugs being set to .5mil cause it to misfire?
stevencos
25-05-2003, 13:15
up
guinnless
27-05-2003, 08:40
No, the extra small gap won't cause any probs under boost.

If I have lost you then maybe you should take it to a pro or if you live near me I'll sort it for you over a brew.
http://www.turbosport.co.uk/images/smilies/smile.gif