help...a seasoned mechanic is stumped! I have a 91 3.1 rs with crank but no start. fuel pressure is 43 psi,compression is 175 through out. has spark. it will start by feeding it brake cleaner through intake....I replaced map sensor,tps,fuel pressure regulator,ign module,checked coil on dist its 800 ohms,checked all fuel injectors...all about 12 ohms,checked signal to all injs with noid light..all ok.only dash light is the one for air bags. I have changed every sensor on this...except oil sender thats tied to fuel pump. maybe thats the one? I am going to feed the aldl link "g" with a hot to see if it will run. and now just recently if feels like ign switch is bad... cometines it will not crank over unless messing with key sw....but this key sw problem just started yesterday while working on it. any one out there with any knowledge of this problem?I have heard some about the diode in key....I think its called a "vats" security system?...if thats my problem would it still crank over? please help! Danny.

 

If it was a security then it would not turn over at all... How long has the car been sitting? Dirty fuel maybe??