305 s/d tpi 5 spd.
the car may sit a few days before started or driven. (not a daily driver). turn the key and hear the fule pump prime. go to start it and sometimes it sounds as if it is about to turn over and then it just cranks. checked the spark and fuel pressure. pressure is at 40. everything else like vacuum lines and connections look good.
after a while ill come back and it will start. plugs pulled and replaced a few weeks ago and they were dark, like it was running rich.
fuel pressure regulator is not leaking or any fluid in the vacuum line.

im wondering if the stock fuel pressure regulator is going out, or the injectors having a problem. any ideas?

 

fuel pressure has dropped to about 10 since a few hours ago. it is the original fuel pressure regulator and injectors. if i can get it started tomorrow ill try to run it through tune pro.

 

put your fuel guage on it. turn the key on and get the inital reading. leave the key on and see if it leaks down, and if it does how fast.

 

gauge was on it at start at a little over 40. its leaks down slowly at about 10 over a few hours..but while under pressure with the key on its holding at around 40.
it seems to be a problem when it sits more than a day without being started and running. after it gets going it will start and run, even the next day.

 

That's not too bad.. how's the cap and rotor look? Probably not the issue but could cause a crank no start concern

 

i replaced them recently with ones i had in storage from another car. i was getting spark to the plugs when i tested everything earlier. maybe the ignition module?

 

anyone else with ideas? if i have spark and fuel why wont it turn over? my only guess is that the fuel regulator is not working properly. any way of testing it to see if its putting ot too much fuel?

 

Check your CTS (Coolant Temp. Sensor) at the front of the intake manifold. Since most of the time when they go bad your ECM will think it's cold out and will throw extra fuel in. Making it rich and harder to start.

If you have a scanner, I would check to see when the coolant temp. is on it. You use a multimeter and check the resistance on the sensor itself.

 

already switched it out with another. for two damn days this car starts and now its doing it again. 40 psi fuel. does this mean im getting the correct fuel to the injectors or is the regulator not working? spark at plug one means im getting spark. so what is the problem?

 

amazing that it only starts when jumped off a ford. fuel psi is at 32 but increases when idleing. regulator? injectors? why does is struggle to start like its not getting fuel. pump and filter are new.

is there a chance the oil pressure sensor above the filter may be a contributor to this problem? i see my oil pressure gauge working correctly when its starting. when it wont start and i have to jump it its pegged out. it shouldnt be cause its not even on the same circuit?

im so tired of this car sitting in the garage cause i cant trust it.

 

Are you saying it's turning over, but won't start. Since it's a 91, it could be VATS since it shuts off the injectors if it has the wrong resistance in the key, wrong key, or bad contracts inside the ign. tumbler.

 

your injectors might be leaking the fuel into your cylinders while the car sits and making it hard to start

 

that theory may explain the dark plugs too

 

Ive noticed this is a problem a lot of people have had with their tpi systems. I had it too with mine and after replacing almost all of the fuel and ignition system, the problem turned out to be broken wires in the ignition coil CONNECTORS. Im new to this site and and trying to figure out how to start my own thread with this but havent figured it out yet, lol.