O/T 93 Suburban inertia switch location

Even with the pump relay bypassed so the pump runs, It still will quit when slowing down for a corner and will not start again for quite some time. Fuel poured in the engine helps to get it going.

I think the common denominators are:
1- signal to the fuel pump relay sometimes
2-injector signal is not proper for demand.

I don't have a fuel injection pressure tester but I will get one if I have to.

Does any body know where I can find the inertia switch (come to think of it, I don't think that is the problem)
Does any body have any ideas.
I don't have another computer to try as a test
Just scraped the old 88 Suburban 2 months ago.

Thanks in advance

The fuel pump relay will turn on for a couple seconds when you turn the key to on. Then it stops until the engine computer sees a cranking signal from the distributor. There is also a 12 v tap wire that comes out of the wire loom along the firewall. Putting 12 volt on this wire directly powers the fuel pump.

Now, the first thing I would check if you brought this to me would be the magnet in the distributor. They crack, you can usually see the cracks and they cause weird running symptoms.

I had a similar problem on an '87. Found the plate that holds the ignition module is steel and pressed on to the aluminum distributor housing. The two metals will react and corrode when moisture is present. Truck would run fine when cold, but would die from underhood heat causing excess resistance through the corrosion. Was a bear to find, was told to check it by a GM mechanic.

I put a ground wire from the distributor cap hold down screw to the manifold. No more trouble.

The ignition module also fires the injectors. If it is not grounded, no fuel.

At least that's how I undestand it. Good Luck!

That truck doesn't have an inertia switch like the Fords do and you can't see the fuel in the throttle body without a strong flashlight and a really good eye.

Did you change the fuel filter? Did you replace the pickup hose at the fuel pump? What codes are you getting?

Dunno, if you replaced the pump and the relay, I just don't think your problem lies in that area. Unless of course, you used an aftermarket pump?

I'd be looking at that EGR valve/solenoid and/or throttle body gasket in the event that the idle speed seems way too high because it really sounds like we have a vacumm leak somewhere.

Allan