j.kenzie@sbcglobal.net

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

j.kenzie@sbcglobal.net

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

Rich9928p

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/

j.kenzie@sbcglobal.net

Thanks Rich,
I'm trying to use that exact test section. I will post additional data.
Dave

Mrmerlin

You might need a new fuel injection relay,
your car has the compound relay

j.kenzie@sbcglobal.net

Thanks, Stan. Can I jumper it, to test?
Dave

PorKen

Check/clean the TSZ spark box connectors. Plug in a known good one to test.

j.kenzie@sbcglobal.net

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

Mrmerlin

Plug in your spare relay you do have a spare

j.kenzie@sbcglobal.net

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

j.kenzie@sbcglobal.net

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

j.kenzie@sbcglobal.net

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

Mrmerlin

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

j.kenzie@sbcglobal.net

Thanks, Stan. I just ordered the relay. Either way, it won't hurt to have a spare, or it fixes my problem.
Dave

Mrmerlin

Keep us posted Dave