That's my latest problem, last week I went down to the shop to work on the rex and it wouldn't start to save my life. It was getting spark, so I checked the fuel line, nuthin. Not even when I turned the key on. So, I figures fuel pump. But today I go down, and poof it started right up no problem. I've been having this problem intermittently forever. First I switched the ign. trigger and internal coil from a spare dist, and that worked. I've got a jacobs on it, but that shouldn't affect ----. I don't know what to do except shoot it with a shot gun. But, I shut off the car for a minute and then it didn't want to start for me again. I think maybe it's just teaseing me.

 

possibly a faulty fuel pump? maybe its 'working' sometimes and not working others?

Only other thing I could say is the wiring to the pump is bad, or the battery.

 

I'm sorry you may also want to check your relays.

 

main relay...

 

check the voltage on the fuel pump when it's on. and yes check the relays

 

I had that problem on a BMW once(I know totaly different) turns out it was a bad pick up in the distributor. The fuel pump relay got turned on buy the disributor pulse, the pick up would work on and off, it drove me nuts. You may have a similar problem, get a wiring diagram and see what turns the fuel pump relay on.

 

broke wire maby. proberly the relay

 

i was gonna replace the pump anyway so, I'll start there and work my way forward. It just pisses me off. It's so sporadic that I can never pin point it. It runs, I shut it off, come back 5 minute later and it won't start. Then it does. The car ain't at my house, so I can't spend all day turnin the key over and over. The battery I yanked from a car in back of the garage, so I know thats crap.

 

main relay sends signals depending what point the car is in..

7 connections to the relay...

starter signal
ground
batt +12v
ecu a13,a15
fuel pump
ignition switch
ecu a12,a14

it sends signals to different connections depending on key position. ...if u want u can give me your email (PM it to me) and I can email you a main relay test and replace writeup some1 did.

 

I had the same problem check the main relay.
This is how I fixed it, It's been 2 months and haven't have a problem since.
http://www.markl.f9.co.uk/howto/elec...main-relay.htm