Coil spark questions - ZDriver.com


240Z, 260Z, 280Z Performance / Technical Discussions related to performance motor enhancements, upgrades.

Reply
 
 
 
LinkBack Thread Tools Search this Thread
Old 10-07-2018, 05:51 PM   #1  
Registered User
Thread Starter
 
dreamz90tt's Avatar
 
Join Date: Aug 2007
Location: Virginia
Posts: 33
Coil spark questions

have googled my brains out and tested everything I can think of but so confused at this point. The ballast resistor on my sons 77 280z started coming apart for some reason and he felt TIU was also going south do to random ignition problems. Short version is tried to direct wire in a GM HEI by passing the ballast. My current issue is I do not seem to be getting spark across the HT lead of the coil.



Trouble shooting I followed the below steps and on 6 getting a limited amount of voltage but not enough to cause spark. Feels like a 9volt bat to the toung at best. (2 coils same result.) if I am getting 12 volts at the + side of coil what would cause it not to fire?



There are some checks you should try before swapping too many parts.

1. Disconnect the plug at the TIU

2. Check the black wire is grounded.

3. With the ignition key ON, check for battery voltage at the Black/White striped wire.

4. Check the resistance across the red & green wies. Should be about 725ohms iirc.

5. Use the multi meter (analoge needle type works best) on low voltage setting (preferably lower than 5volt scale) and check for small voltage spikes across the red and green wires while cranking the engine. You should see 3 small voltages peaks per revolution.

6. Remove the HT lead from the distributor cap and connect it to a spare spark plug (or remove one from the engine).

a: Connect a jumper wire to the coil ( - ). Turn the key on and tap the junper wire rapidly on the car frame. You should see the spark plug sparking when you tap the wire. Be carefull for shocks from the coil.

b: You could also do this test through the blue wire and black ground wire at the TIU terminal block to check the blue wire works correctly.

7. Check coil resistance. It should be under 1.0 ohm across + & - terminals. Higher resistance can mess up the HEI unit.

If all these checks work out, then the HEI is not wired correctly of it is damaged. If you fry one, they sometimes come back to life, but not for long. So if you have any doubts about the module, I would change it.


dreamz90tt is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
Spark plug #1 wont get a spark and all other 5 and getting spark Fairladyz1990AF 300ZX (Z32) Forums 7 04-24-2014 04:15 PM
no spark at coil thumper9 280ZX (S130) Forums 13 04-10-2010 11:47 PM
coil looses spark car wont start when hot ? nismo619 280ZX Performance / Technical 5 04-07-2008 01:00 PM
no spark from coil with pics <UPDATED CONT> intuitdriver 280ZX Performance / Technical 13 09-15-2007 06:03 PM
no spark from coil intuitdriver 280ZX Performance / Technical 6 09-13-2007 04:19 PM


Bookmarks

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -7. The time now is 06:00 AM.


© 2018 MH Sub I, LLC dba Internet Brands
We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.