SO lately I have been having some problems with my fuel pump priming when I go to start my car. It is a 1993 stock D15 Del Sol. When I go to turn the key to start the car, the 3 cluster lights come on, CEL, Oil and batt. Now I guess the process is: turn key, main relay clicks, pump primes, CEL light goes out, car is ready to start. I am having a problem somewhere in between the key turning and the relay clicking. I turn the key and the time varies when the relay clicks, it could be right away or it could be (as this morning) about 20 - 30 minutes. The way i know the car is ready to start is when the CEL light goes out (I dont hang around in my car for 20 minutes waiting for the pump to prime, I turn the ignition, go back inside and watch some TV, then go out and check if its primed) It seems to be worst on wet days, like when it rained yesterday and it gave me problems this morning. At first I thought it was my fuel pump, all the checks out, then I thought it was my main relay and stuck a new one in there, same problem with both relays. I don't think it's my ignition switch because the dash lights up, AC and radio come on when I turn the key, just relay doesnt click

Has anyone ever had this problem? what should I check next to diagnose it?

Thanks in advace
Carlos

 

Clean and tighten the G101 ground wire attached to the thermostat housing.

 

I will try this and report back, thanks for responding

 

I'm having the same problem! I posted a little ways below your post but didn't explain as well as you did. I too will try cleaning the ground on the thermostat housing and let you guys know if it worked or not.

 

alright, so last night I was able to loosen that ground, clean it up and retighten it back. Once i was done I took my multimeter and checked for continuity from that ground to several other grounding locations (battery, chassis) with good results every time.

However, the problem still exists, I left it sit overnight and this morning the problem continued.

Anyone have any ideas what my next step would be?

 

Do the tests in the diagrams and post the voltage or Ohm reading at each step. Where the diagram indicates a continuity to body ground test do a resistance (Ohm) to body ground test instead.

1) Carefully inspect 15A hood ECU fuse 31.

2) Follow steps in diagrams below. The ACG fuse is dash fuse 24. Also, A25 is actually directly above A26 in ECU connector A.

 

not sure why anyone hasnt said this yet.. but i had the same exact problem and for me it ended up being the main relay under the dash.. it would do the same thing... just at random times not prime the fuel pump. all other electronics worked fine... CEL would also stay on.... i could leave the key in the ignition smoke a cigarette and half way thru it would just randomly prime with out me moving anything. you could either re "sodder" <sp?> the points inside the relay or try a new/used one

 

This does not absolutely rule out a main relay problem but does address your point.

 

i just read the thread again and still cant find where the guy said that haha.. but yea.. its just something else to look at.

 

Glad i found this I am having the exact same issue.