S3 coil resistance
S3 coil resistance
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Discussion

techbotics

Original Poster:

1,805 posts

211 months

Saturday 18th February 2012
quotequote all
hello there I seem to be loosing all firing under hard accell above say 3200rpm.. Not a missfire all sparks (maybe) seem to stop.

she seems ok when cold but a couple of miles after starting this happens I dip clutch and she never dies. I reseated the by Leads earlier in week and the prob went away but back now. Seems worse in the wet but not 100%

anyway by leads seem ok and a coil is cheaper so thought I would check this first so my question is what resistance should the coil be when measuring LT and HT coils?

I get 0.8ohm LT and 7410ohm HT.

all other ideas welcome

thanks

Damian S3

mep12345

2,061 posts

230 months

Sunday 19th February 2012
quotequote all
Damian,

What you have got is consitent with what both my coils give and what the Haynes Manual (Granada) says, namely Primary Winding (LT) 0.72-0.86 Ohms and Secondary Winding (HT) 4.5-7 KOhms

I have (as you will have read done lots of chasing on this type of subject recently and have now ruled out ignition. Although not TVR directly the links below were exellent in helping me (from you description Ignition module may be the issue)

Link 1 - diagnostics for ignition system

Link 2 - Ignition Module Supplier - I think I may have had his last one though

Hope these help

Mark

techbotics

Original Poster:

1,805 posts

211 months

Sunday 19th February 2012
quotequote all
thanks for the reply and links.. Will go and digest..

saw some arcing when I put the coil back I seem to have it sorted now will road test tomorrow and see how she goes.

talking to trackvroad about my 24v engine so may get on with that project.. It should fix things smile

thanks

Damian S3

techbotics

Original Poster:

1,805 posts

211 months

Thursday 23rd February 2012
quotequote all
hello all thought I would post an update to this story..

looks like it was water in the fuel.. The filler neck drain hole was blocked + car outside + lots of Good old Yorkshire rain.

so draining rest of fuel off and see how she is tomorrow.

thanks Damian S3