Just picked up a decent 84 auto. It was running rough but after a rotor and cap if now runs perfect but developed a no start. I put in Freon which caused the A.C. and heater fan to blow a fuse. At that point the car developed the no start. Hit and miss when I pull the alarm relay the car will start and run perfect but when placed into gear the car dies and back to square one. What could cause the car to die when placed into to gear. It seems to be something with the alarm telling the car to kill when placed into gear.

 

Replace the alarm relay and bridge the alarm system at the Z plug - Z1 to Z4 for USA MY84. This is the process for disabling the alarm.

Let it run at idle and play with the large bypass screw at the front of the throttle housing. If there isn't much immediate change in your idle speed as you adjust the screw, then that is indicative of significant vacuum leaks.

 

The car has been running flawless with perfect idle. This seems to be more of a fuel or more likely an electrical problem. If the alarm relay gets bridged does that take the alarm completely out of the equation? It just seems like something in the alarm system is cutting power to the fuel system. Is that even how the system is designed for disablement of the car?

 

The jumper wire must be placed between Z1 and Z4, not the relay. This bypasses the alarm completely.

So the car starts with no alarm relay and doesn't start with the relay in place, correct? Bridge the Z plug as I've suggested and please report.

 

There'a an alarm relay? Is it in the CE panel?
First I've heard of it. Although that doesn't really mean all that much.

The alarm 'disabler' works by cutting the 'activator' power to the computers. The relays don't 'energize', so you get no spark, no fuel injection and no fuel pump. The bypass in the plug in post 2 gets power to the relays when the key is on.

 

Relay IV

 

Kiln Red is correct, bridge the pins in the Z socket as described.

For anyone else referencing this in the future, here are some relevant threads:
https://rennlist.com/forums/928-foru...rm-system.html
https://rennlist.com/forums/928-foru...ory-alarm.html

But something bothers me about the fact that you blew a fuse when you recharged the AC -- something is not right. Please read the "New Visitor" sticky and follow the recommendations for cleaning and maintenance of the electrical system -- we don't know that you are starting from a good working electrical system and some basic cleaning and checking will potentially help out on many issues. It's also possible that the problem is unrelated to those electrical issues. Might a vacuum line have fallen off, causing the engine to stall under the load of engaging the transmission?

One more thing, I can't pass up a chance to refer you to my "electrical system guide for dummies" on how to read the '83/'84 wiring diagrams. This thread also contains links to all the diagrams for your car.
https://rennlist.com/forums/928-foru...r-dummies.html

 

this doesn't help you with your problem, but you have a pretty awesome man cave

 

Having trouble finding the Z plug location?

 

Rightmost of the two smaller receptacles in the very middle of lower board. See here: https://rennlist.com/forums/928-foru...all-years.html

 

Ok that link really helped. I will look further in the morning.

 

Do not jumper z1 go z4 on 1984.
Do not jumper z1 to z6 on 1984.

You will have a shower of sparks.

1984 is Z4 to Z6.

This is true for 1984, both euro and usa.

83 and earlier are z1 to z6.
No idea where z1 to z4 comes from.
Kiln red, what you talking bout?


Also ignore all advice to use 83 wiring diagrams to avoid having to use the more cryptic format of proper 84 diagrams. There are too many differences, such as this alarm difference. Use only 84 diagrams for 84 cars.

 

...

 

https://rennlist.com/forums/928-foru...ory-alarm.html

Chris, see post #7.

Not sure if you still have an '84. I do and the Z plug is bridged successfully. That said, hold the phone OP. I'll be home shortly to verify my bridge arrangement.

 

Open second link, under post 7 of the current thread.

That thread has link that shows actual diagrams that show the difference between the 83 and 84 alarms.
Use that to guide. It very clearly shows reference in the wiring diagrams to the bridging pins.

In today's thread here, Kiln quoted a recent 2016 thread where I must have gotten it wrong.and the bad advice came from me actually. It's a nightmare that I did that. And as soon as Austin or somebody else verifies, we will fix that thread accordingly.