my 87 blazer wont start until it turns over for 15 seconds? i changed the relays on the finder thanking it was a fuel pump relay but i noticed that it starts up after the oil pressure gauge moves to 15 psi or if i give it a shot of starting fluid. after it starts it runs fine???????????? any HELP OUT THERE 2.8 auto matic TBI

 

It could be a faulty oil pressure sending unit.

My '87 2.8 S10-Blazer has two diferent oil pressure sending units. Most repair manuals show either a 1 wire, 2 wire, or 3 wire unit. I have a 2 wire & a 3 wire units. The oil pressure sending units are located next to eth oil filter. Take a look at your and post up what oyu have.

Take a look at Autozones web site. They have wireing diagrams for our trucks on line.

 

This is quite inlikely, but its a cheap fix, and its easy to check. If you live in a cold environment, and some moisture got into your distributor cap, it may have frozen, expanded, and cracked it. It is held down with two screws, and it costs less than ten bucks. Just take it into a dark room and put a flashlight under it to see if there is any light coming through where it shouldn't. Its a long shot, but its cheap.

 

my 88 with the 2.8 did the same thing and i dident know what it was so i went and got the tbi unit off my old one (blown moter) and put it on now it starts right up