Okay having problems with no spark and have researched a bit but just have one quest. What does the AFM have to do with no spark? Dosen't that just control the amount of air blah blah blah. Some people said unlug it and see if you have spark. If this works why does it happen and does that mean the AFM is malfunctioning. Sorry for the noob quest. but would appreciate the help, thanks

 

As far as I know, the AFM is completely ignored while the car is starting. I know this is the case for fuel, and I didn't know it had any effect on spark at all at any time.

What all have you tested so far, so we know where to start?

 

The only reason it could kill spark, is if the 5vdc REF voltage is shorted to gnd inside the AFM. Do that and you kill the ref voltage for all the other sensors and the ref voltage inside the AFM that is used for ............spark and fuel.

So, if there was a short inside the AFM, you could remove the elect plug from it and now the car will START. Staring is not dependent on the AFM for fuel. Fuel is determined by an internal fuel map inside the ECU, til the rpms get over 500rpm, where upon the afm takes over. No plug on AFM will result in a start, but only for a moment.

 

well you really got me thinking there. I know the AFM also works as a cut off switch for the fuel pump. thats why you have the yellow bypass connector on the PS shock tower but. I have never heard anything about it controlling spark. this sounds like a question for Hailers!!!

 

there you go he posted at the same time!!!!

 

try testing ignition parts. eg. plugs, wires, coils, igniter, etc. as far as i kno AFM only meters the amount of air going in, therefore letting the ecu send the neccessary amount of fuel.

 

I answered the specific question as to HOW the AFM could cause no spark and WHY others recommend removing the AFM plug to see if that is the problem. The AFM is NOT used during Starting, so if the engine starts with the afm plug disconnected, then the problem most likely is a bad afm for the reasons mentioned.

IF you have no spark at all, then I'd first check the ENGINE fuse in the interior. IT powers the Main Relay which in turn feeds the coils.

You check the small, white, two wire plug for the LEAD coil to see if there is batt voltage on the black/yellow wire. IF it has batt voltage, good. IF not, find out why. And it's assumed you already checked the EGI fuse(s). Goes without saying....I hope. Both Lead and Trail coils don't just suddenly go *bad*. Sillyness.

Or there's the old standby that is easy to do. Pull the CAS or use a spare CAS. Connect it to the harness. Key ON, Spin the bottom gear of the CAS and listend for spark/injectors clicking. No spinning of the starter, just spin the bottom CAS gear i.e not wearing out the starter/apex seals, oil seals.

 

Checked everything you said Hailer except CAS. I did test the Ohms for the CAS but havent been able to try a different one yet but thanks.