JKE

Hello all Iam working on a 1990 jeep that I cant get started. I had weak spark at first so I changed the pugs and the CPS sensor. The spark pick up. Then I was not getting fuel. I put my Fuel tester on the fuel rail and I have gotten 38 psi on the rail. The issue is iam not getting fuel through the injectors. I don't think iam getting power to the injectors to open them. Please help me out with this.

DFlintstone

You probably want to start by checking/cleaning your grounds. 1,3,4 and 5 here is highly recommended> https://www.cherokeeforum.com/f51/cr...x-tips-153657/ You will find Cruiser's tips right on top if you click on the link in my sig. as well.

The gang on your dipstick mount is pretty important!

JKE

I tride that yesterday. Cleaned all grounds and unplug all wires to check for corrosion. Still no start

cruiser54

TEST that new CPS.--post 7.

Did you do #4?

DFlintstone

x2^. It only takes a couple of minutes to check the CPS. Also see if it fires with a shot of quick start.

I made a "noid light" to see an injector firing. What ended up working was using the bulb to a 3 cell flashlight. If your spark is crisp and blue and the CPS checks OK you might give it a try. > https://www.youtube.com/watch?v=nPdk...ature=youtu.be

It may not fire with spark and fuel if there is a problem with the MAP>
There is a brittle little tube. It comes out of a rubber plug, low on the engine side of the throttle body. It runs back to the firewall, then up to your MAP sensor sort of high up there near center on the firewall. CRUCIAL!! The MAP will tell the ECU to dump fuel with less/no vacuum. Any crack or blockage and it will be pig-rich. (black smoke, fouled black plugs). You can pull the line off the MAP and feel for vacuum with your finger. If it runs!