Hi. I'd appreciate some guidance with a problem I'm having with my 1985 GS (12a). The car was running perfectly, then I started noticing that the tach was behaving erratically, and then the car started stalling. Well, that pointed to a bad trailing igniter, so I replaced that--albeit with a used one. I've searched the board and gotten some other tips, so I replaced the fuel filter, the fuel pump, the cap & rotor and plugs. What I'm noticing now is that the car is a bit more difficult to start initially (all you used to have to do was virtually breathe on the ignition key and she'd fire right up), and, perhaps more telling, is that there's a mild misfire at idle and definitely upon deceleration, as well as a tendency to bog, stall, or threaten to stall if you blip the throttle. If you're gentle with the throttle, you can slowly raise RPMs. The car seems low on power, too, as though the secondaries aren't functioning properly. I've tested the coils and they seem to be fine. I've had the motor running and unplugged the leading ignitor and it definitely affects idle. Unplugging the trailing ignitor now seems to have no effect. I've not found any vacuum leaks. There's no smoke coming out of the tailpipe at any time. I'm down to thinking I still have a bad igniter, or a problem within the fuel delivery system. I've not driven it any significant distances for fear of another stalling episode, so I can't say how well it does on a driver longer than just a couple of minutes. I've done my best searching the site for other tip; any pointers would be most appreciated!

 

Sounds like it's ignition related to me. You can try replacing the trailing ignitor again but I'd test to be sure you have spark to all four plugs first and then go from there. Bad coil maybe? Good luck!

 

Is your tach still jumping?

 

The tach doesn't appear to be jumping any longer.

 

Bad plug or wire maybe.

 

Try eliminating the ignition first.
Throw a timing light on each plug wire. Even though you will not be able to see the timing mark on rotor#2, you can still see if it's jumping around irratically..or not firing at all.

 

Okay, timing was a bit off so I've corrected it. A lot of the problems have been rectified with another new set of plugs, but what I seem to be coming up against now is that the car still seems down on power, revs fine when sitting, but when under load has a hard time moving past 4k and definitely doesn't want to move past 71-72mph...just no 'oomph' in her anymore. Noi passing power on the road. Just tooling around is almost back to normal. Compression is fine, I've heard nothing when banging on the cat...any other ideas? Thanks a million!

 

Maybe your secondaries aren't opening.