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i got a weird problem with my rb20 ignitor dieing after i switch the car off and on again. i took the sparks and coils out and rested them on the block and spun the CAS by hand and i got no spark. so i went to the wreckers and got a 2nd hand ignitor and plugged it in and spun the CAS again. this time i got spark. so i put the car back together and started it up without a problem. i switched it off and tried starting it again - no spark WTF!

the CAS is working and the ECU is sending a signal for the sparks to fire and the coils are getting 12V and an earth. so i think ive narrowed it down to the ignitor

any ideas on how to fix this? is the r33 ignitor more reliable?

random pic of what an ignitor looks like on the inside

post-74771-0-09602500-1311985777_thumb.jpg

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ignitors are still frying. i took an ignitor that has been in my car and put it into someone elses car and their car didnt work.... the car runs fine witha new ignitor, but then i switch it off and switch it on again and the ignitor is fried

i measured the resistances of all earth wires and they all looked good, so i didnt bother beefing them up any more

i ended up making an ignitor with bits from jaycar. first attempt was a learning curve, as was attempt no.2, 3, 4, 5, 6, 7 etc. finally i found a configuration that sorta worked but found that transistor 1 and 3 fried after a short period of time. my ems stinger runs a wasted spark, so i removed transistors 1, 2 and 3 and linked transistors 4, 5 and 6 in their place. the problem seems to be solved but ill have to test it some other time. its midnight now and i think all the backfiring from the flooded engine is pissing people off. i hope its flooded anyways. either that or the spark isnt strong enough and i dont wanna increase dwell and fry something

i dont believe the ems stinger is to blame otherwise transistors 4 and 6 would have fried too (wasted spark). i think the problem lies in the loom. even though i couldnt pick up any reading from the signal wires (6 pin side of the ignitor) on the multimeter or oscilloscope, i think that somehow, a power source was coming from somewhere and causing the base of the transistors to stay 'ON', causing them to overheat from the charge of the primary winding of the coils. having said that i still have no conclusions as to why it would only die after i tried starting the car again, only theories

if all goes well i think i might start selling my little creations. and as far as i can tell, they will work on any car that runs an external ignitor just as long as you get the pins right. cheaper than any new or second hand ignitor and takes a lot more shit. its repairable, lighter and versatile... its just better

Edited by markdem

dunno what a jobby is... it is piggybacking if thats what you mean. and it was done by previous owners

the issue randomly came about one day. simply didnt start. i used the down time to put a new engine in and after completion it started up as soon as i turned the key. then 2 days later it wouldnt start and its stayed that way since

dwell time is not excessive at 2.75ms and if it were, it would cause all of the ignitors to fail, not just the ones connected to ignitor pinouts (pin-ins?) 1 and 3

found another clue as to why it wont start. im still getting spark when i spin the cas by hand, but as soon as i use the starter motor, the spark disappears. hence the original problem. im not good enough with electrics to fix this one myself. im sending it to a shop.

Edited by markdem
  • 2 weeks later...

got the ecu tested by the main EMS guys in sydney. they say its ok. f**king electrician. i made my own loom to the starter motor and ignitors and hey presto! the car gets a spark when i turn the starter motor :) yay!

now i just cant get the thing to start. it puffs and backfires and gives an occasional powerstroke. im gonna steal the compression tester from work and test out compression again just incase something went bad.

my only question is: is it easier to ignite a rich or a lean fuel mix?

i plan on messing around with the fuel ratios a bit to aid in getting the engine started. im leaning towards a rich fuel mix coz on the old carby cars you had to pull the choke sooooo.... yeah just fiddling. i know, i know i shouldnt have to adjust fuel air ratios at all - especially considering that the engine already started several times on the current fuel air settings

Edited by markdem

Replace the spark plugs first before messing with the tune. Chances are that because u had no spark with u ignitor issues the plugs are fouled. Check them and see.

Also its easier to ignite a stoich mix :D

  • 1 year later...

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