View Full Version : Fuel System Issue - 1989 Toyota 4x4

01-17-2007, 01:30 AM
Hi, I’m new to this forum and could really use some help with my truck. I have a 1989 V6 4x4 4Runner that was working fine until it was stored for the past 3 years. I am unable to start the engine. The engine fires up briefly with starter fluid, but does not stay running due to zero fuel pressure.

I removed and tested the 'Circuit Opening Relay' and verified that there was continuity between terminals STA and E1, B and Fc, and no continuity between terminals B and Fp. I performed this test based on a Toyota manual. I can also hear a clicking noise from this relay when turning the ignition key of the car; I believe this relay is not my problem.

I then directly jumped the fuel pump with the positive charge from my battery and the fuel pump still does not work. I believe the fuel pump is stuck and may work if I clean it. However, I am unable to remove one of the hoses from the 'fuel pump sending unit assembly' which is fastened onto a threaded (and easily bendable) pipe. I am also unable to properly remove the wiring. How do I remove this hose and wiring without damaging the ‘fuel pump sending assembly’?

Any tips in troubleshooting and restoring the fuel pressure on my 4runner is greatly appreciated.


01-17-2007, 09:41 AM
Bad fuel pump probably. The pump and stuff all comes out in a chunk. You are n luck as this is not a "drop the tank" repair.

You can stick a test light on in place of the fuel pump leads and make sure the electricals are OK. The only other part of the picture is that the fuel pump only runs when the key is in CRANKING position OR the MAS air flapper sensor is open. That flapper door may be stuck from sitting too.

However, it is my experience with older toyotas that the fuel pump will be the problem. It only takes a little rust to seize 'em due to the close tolerances. The Toyotas that sit a few years often have this problem.

Under the rear seat, remove access panel. unplug wires and hoses and pull out the entire thing. Go get a new fuel pump. Pop it onto the end of the bracket/sender thing and stick it all back together. No big deal. You really have to pull the wires and all those hoses off to get 'er done.

01-17-2007, 09:58 AM
Possibly the problem, but perhaps not...