1988 s10 not starting

[tk1251k]

Right after adding gas and getting onto interstate up to about 70 mph it just lost most of its power still run but mot much power. Got it off to the side of the busy highway. SO far changed the fuel filter no help. Getting gas runs briefly on idle then cuts off. We got to run about 20 mph to get off the highway by feathering the gas. Had it towed home last evening. Now the fun begins. All hoses seems ok but I need to check closer. Truck ran great up until that point. Has only 34,000 miles on it. Any suggestion tips or help appreciated. Thanks in advance.

[speedygonzales]

When ever there is a problem, start by eliminating the most likely suspects. Then move to the lesser likely suspects.

So in this case focus on fuel delivery.

First start by checking fuel pressure. While fuel may be traveling, it may not be at a pressure level that is needed.

If it is at the right pressure, check delivery. It may have a restriction or the opposite, it may be dumping too much. However either of these usually effects the pressure. One of the ways to check delivery is to see the effects on the spark plugs. However, keep in mind that a black (sooted up) plug does not necessarily mean it's from too much fuel. It could be a weak spark from a badly corroded cap and rotor. I've had that problem a time or 2.

NOTE: check oil level often and smell the dipstick for presence of gasoline.

Sorry I'm not familiar with the 4 cylinder if that is what you have but many throttle body engines of the time did not have a place to hook up a pressure gauge. You had to remove the fuel filter and put a gauge block in place to be able to read pressure. So if you don't see a schrader valve, more than likely you will have to.

These TB's were widely known to have bad FPR diaphragms. You could just pull yours out to see how stiff it is. Be sure to relieve the fuel pressure before you do.