08-24-2008, 01:42 AM
Join Date: Oct 2007
Total Cats: 0
Weird Problem that is hard to diagnose.
Car: 1990 Miata 1.6, 5-speed, M45 Jackson Racing SC. Afpr, Msd boost retard.
If it is hot outside my brothers car starts well. If it is under 90 degrees it doesn't start. It will start and die. start and fail. But as soon as it fires enough to get it to roll, it instantly runs.
It acts like a fuel pump halfway working. It hits to fire up fast and dies.
When it is hot, it fires and runs great.
I told my brother to put our spare O2 sensor in. He never did.
But he has replaced:
Factory fuel pressure riser (spare part in garage)
Fuel pump (new)
It seems kinda like the choke isn't working. And it is progressively getting worse.
Now it is starting to cut out on the highway. Normal driving and the narrowband goes to lean and it stalls and then kicks back in.
I need to find out which relay is for fuel, and we may swap in my old AFM tommorrow.
Will a bad AFM do this? ANY Ideals????