what is the Exhaust Heat Control (heat riser)

[Boingo]

I recently got a hold of this 1986 Ranger xlt 2wd with a 2.9. Already had a fresh engine and tranny. Everything is pretty much new in the last month from the fuel pumps, regulator, iac, egr, sensors, ecm, new distributor, and all inbetween. It's been sitting in a desert climate since 99. I had. It running smooth for a week or so in the yard, not on the road yet. Now it starts right up, but has a wobble due to a miss it seems. Far as I can tell, no vacuum leaks. The code I pull with my obd1 reader is 89. I'm guessing the Exhaust Heat Control (heat riser) solenoid circuit is the EGR ? Does anyone know? I'm stumped at this point what to do.

 

[fastpakr]

89 should be 'Converter Clutch Override Circuit Failure (2.9L, 3.0L & 4.0L)'.