Good evening all,

I have a 1986.5 with a rich start issue ( blowing rich exhaust smoke ).
Question, I have checked the temp2 switch both at the sensor and the LH connector and the resistance comes up as 3.3 k ohms at 15 degrees Celsius.
Would that resistance cause a rich start condition. It is in the range according to the manual although at the higher end for the 0 to 30 Celsius range.

Have also checked the MAF by starting with disconnected ( its worse disconnected ). Same goes for the o2 sensor.
Ive checked the FPR vacuum ports for fuel and have jumped the fuel pump with hoses disconnected ( no fuel coming out of any of the vacuum ports.

Also checked WOT switch and all seems well there.

In the process of doing an intake refresh but would like to figure it out before tearing to far into the project.

Any tips would be appreciated

Cheers, Gary

 

You have to make sure that your car has everything perfectly working including the MAF and new O2 sensor f
The throttle shaft bushings for vacuum leaks
new rubbers fo r the plenum center rubber
once all these pieces are perfect then you can adjust your MAF with the engine running to get the mixture right
It sounds right now that your MAF an O2 sensor may be out of whack
Note the MAF can be adjusted on your car for mixture look up a thread I wrote how to adjust your MAF for an
85/86

 

If you're unsure if the MAF has ever been rebuilt, then I recommend to have it done WYAIT. You haven't properly tested the MAF just by seeing if the car will run better with it disconnected. Even following the instructions for testing via the WSM won't guarantee that the part doesn't need a rebuild, so take it with a grain of salt.

 

I'll add to check that all 8 cylinders are firing (spark), could have a dead cylinder or four of them (coil), black smoke is indication of fueling being way off.
It's not easy to notice a non firing cylinder, way down on power is and that usually is an indication that four of them are out

Pull the plugs and look

Dave K

 

Thanks everyone for the help, all good tips.
I have read the thread on MAF adjustment but my MAF doesnt have the adjustable pot by the fuse panel or on the unit itself ( just a metal blanking plate ).
I'll start checking for good spark but since it fires up pretty well, I didn't think of going there initially.
I will likely ship off the MAF for a rebuild, get new wires and redo the injectors but didnt just want to throw money and parts at it without figuring this snag out first.
I'll keep plugging away at it and check for shaft leaks etc.
More to Follow
Thanks guys !

 

BTW, the MAF metered out at just 100 ohms but like I said, the adjusting POT is blanked off ( should be adjustable on the MAF for 86.5 right ? )

Maybe its not original equipment.