Ljet crank no start NO spark
#1
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Hi guys
I have another thread about my thermotime switch, but I think this is probably a separate issue.
For the past couple of years my car, 84 US automatic, has been getting more difficult to start. I can smell gas after long cranking so I think I have fuel delivery. Jumped the FP relay, FP audible, but no change.
I checked the coil output to the distributor and I have NO spark. Checked with spark tester and timing light lead. Green wire was replaced 4 or 5 years ago. Coil unknown age. I will go through ohming out the coil lead and the coil itself, but any suggestions are appreciated.
Thanks,
Dave
I have another thread about my thermotime switch, but I think this is probably a separate issue.
For the past couple of years my car, 84 US automatic, has been getting more difficult to start. I can smell gas after long cranking so I think I have fuel delivery. Jumped the FP relay, FP audible, but no change.
I checked the coil output to the distributor and I have NO spark. Checked with spark tester and timing light lead. Green wire was replaced 4 or 5 years ago. Coil unknown age. I will go through ohming out the coil lead and the coil itself, but any suggestions are appreciated.
Thanks,
Dave
Last edited by j.kenzie@sbcglobal.net; 02-29-2020 at 10:26 PM.
#2
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Hi guys,
I have some data:
No spark at coil wire tested with spark tester and timing light
batt voltage: 13.2V
Coil measurements:
terminal 1 voltage: 1.7V
terminal 15 voltage: 4.5V
coil wire resistance: 1.1 K ohm
coil secondary resistance term 1 to 4: 10 K ohms
primary resistance term 1 to 15: 0.5 ohm
So coil seems OK. Will check green wire connections and distributor.
Thanks very much,
Dave
I have some data:
No spark at coil wire tested with spark tester and timing light
batt voltage: 13.2V
Coil measurements:
terminal 1 voltage: 1.7V
terminal 15 voltage: 4.5V
coil wire resistance: 1.1 K ohm
coil secondary resistance term 1 to 4: 10 K ohms
primary resistance term 1 to 15: 0.5 ohm
So coil seems OK. Will check green wire connections and distributor.
Thanks very much,
Dave
Last edited by j.kenzie@sbcglobal.net; 02-29-2020 at 10:27 PM. Reason: wrong reading on dvm
#3
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The factory workshop manuals have an excellent diagnostic test flow for no spark in Volume 1A beginning at page 28-11. The manual can be downloaded at http://www.ligeti.com/928/
#5
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You might need a new fuel injection relay,
your car has the compound relay
your car has the compound relay
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mkhargrove (04-03-2020)
#7
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Check/clean the TSZ spark box connectors. Plug in a known good one to test.
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hacker-pschorr (03-01-2020)
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#8
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Thanks, Ken. This problem has been coming on for some time, consistent with building corrosion or gradual failure of ignition box. I'll be looking at it.
Dave
Dave
#9
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Plug in your spare relay you do have a spare
#10
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Hi Stan. I do have a spare fuel pump relay, but no fuel injection relay. Never knew I'd need one. Can I make a three way jumper? My green wire is pretty new and I understand the ignition modules on these cars rarely fail. I'm looking for single component failure somewhere here. It looks like I have good voltage to the coil and the coil resistances seem OK. Sounds like coils rarely fail also. So I like the idea of relay, relay, relay...
Thanks,
Dave
Thanks,
Dave
#11
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BTW one of the drawbacks of a supercharger install is that it makes access to many components much more difficult. I will get there in checking the ignition module and green wire connections, but I have to remove some SC piping to do it. Just takes time. Also I'm working off a ladder, since the car is on a storage lift. I'm getting old too. I'm not complaining, just explaining why I might seem lazy and just want to check easy things first.
Thanks for all the help.
Dave
Thanks for all the help.
Dave
Last edited by j.kenzie@sbcglobal.net; 03-01-2020 at 10:25 AM.
#12
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Hi Stan,
Looking at the 84 wiring diagrams (different than the 83), it looks like I can jump the L-jet (AFC) relay with a Y-jumper going terminal 30 to two terminal 87's. I may give that a try unless you see a problem.
Thanks,
Dave
Looking at the 84 wiring diagrams (different than the 83), it looks like I can jump the L-jet (AFC) relay with a Y-jumper going terminal 30 to two terminal 87's. I may give that a try unless you see a problem.
Thanks,
Dave
#13
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I would suggest to get a new relay and use it ,
many times a jumper has fried an otherwise perfectly working harness.
Given where the car is you should be using the part that will only work in one position
many times a jumper has fried an otherwise perfectly working harness.
Given where the car is you should be using the part that will only work in one position
#15
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Keep us posted Dave