I have been driving my 85 iroc all summer with no issues. Tonight I pull into the house and the SES light come on and I notice the cooling fan isn't running and the temp guage is up near 220. Idles low and low on power. I jump A and B and pull code 34 and 42. Clear the ecm and it now runs fine as well as the fan coming normally like it used to.
I searched some and found 34 is maf and 42 is electronic spark control. Anybody help me out as what to test?

Nick

 

i have the same prob with my 86 305 tpi thw MaF runs everything try testing that considering it basicially runs the timing through the ecm...havent verified yet but i had codes 32.34.42&43 which all tie into the air flow/density sensores...since a cleand the maf only 42 shows now but still runs like crap with engine detonation

 

Took a 30 minute drive today and it happened again. Idle drops very low and the SES light came on. Car was low on power. Code 34 and 42. I cleared them and then drove another hour with no problems. Where do I begin to look? The car is a totally stock and original 85 iroc.

Nick