Motor Shuts off while driving when hot, intermittent NO Start sometimes as well....??
 

So out of nowhere my 1995 Blazer started feeling as if it was shut off for a split second and then slammed back on. It was the first time I drove it far in about a month and after an hour of stop and go traffic we finally started moving 55 mph again. That's when out of nowhere it felt as if the car shut off for a brief second and then slammed back on. All the lights, dash, AC, electrical, etc stayed on without skipping a beat.

I limped it to the destination while this continued to happen here and there, sometimes more often and longer then prior, before parking her at my arrival. After about an hour inside the grocery store she wouldn't start when I came back out. I tried to start her a few times and got nothing but a crank...?? I spent some time looking up a local tow companies # while keeping on trying to start, but at the same time not killing the battery and then wallah she started for me. As I started to drive towards home, it started acting up again, briefly slamming on and off, progressively happening longer and longer until finally I was stuck on the side of the road. After about a half hour wait in hopes of a restart again, I finally called a tow truck and had it towed to my mechanic's shop. Would you believe by the time the tow truck arrived it started right up and was able to drive on to the flat bed.

It gets to the mechanic shop and they have it for a week w ZERO no start issues and no limping along issues either..?? They performed a fuel pressure test and leak down test all of which passed..?? I pulled the truck out of there as to not to hold up their space and time too much with hopes of tinkering w it myself.

Any idea where to start...?? I do have some pretty good / involved mechanical experience and brought it to the shop bc Id rather pay and be driving asap again then toy around w her but it appears that is not going to happen.

I'm thinking CPS...? Drive around w my scanner hooked up and see what happens w RPM signal...??

Or hook up a permanent fuel pressure gauge...??

Also there are NO check engine lights / codes...??

Any other ideas...??? Thank you in advance, meanwhile I'm off to do some forum searching.

Drive around with a fuel pressure gauge taped to the windshield to see if fuel pressure hiccups. Also listen to get familiar with the fuel pump hum at key on so you can listen when your having no start.

Have the stuff in your truck so when you get a no start get under the hood and see if you have 1" of blue spark across the gap while cranking.

George

There's a Chilton subscription online available for 29.95 for the year... Wondering if I should get it...??

I'm thinking of mounting an permanent external pod for a fuel pressure gauge on the front hood.

Any idea where the test port is for Fuel pressure...?

Underneath, the fuel line disappears into the frame. One would think right off back of manifold / firewall but I didn't see anything... I'm going to check better / again right now.

EDIT: After getting under her again I see the fuel line goes 180, up and over the transmission. Whole area looks familiar bc I once changed the transmission myself. I'm vaguely starting to remember why I'd rather pay a mechanic.

Uptop, after looking down behind the motor, all I see is a distributor snugged back there. No fuel lines.

What if I made grabbing fuel pressure easy, made my own port right after the fuel filter and send it up to the gauge...?

Man I miss having access to ALLDATA.

I do have a 1995 "W vin" I still don't see a test port by my distributor.

Found this in a sticky:

Fuel Pump Maximum Output Pressure And Leakdown Test

The pump must be capable of supplying sufficient pressure, and be able to hold it after the pump shuts off. This is most easily tested at the fuel filter outlet, (forward connection on the filter). It requires an adapter between the filter and the pressure tester. There is list below with the parts necessary to build one. All fuel pressure and flow must end at the tester, with no fuel allowed to the engine. Disconnect the fuel filter outlet line from the filter. Connect the adapter to the filter outlet and connect the pressure tester to the adapter. Activate the fuel pump. Pressure must be 73psi to 108psi. Deactivate the fuel pump. Pressure must remain above 55psi for at least 10 minutes. If this leakdown test fails, there is a leak inside the fuel tank. If leakdown is within specs on this test, and leakdown at the service port is excessive, there is a leak in the plenum.

Is this forum always this slow...???

I use Mitchel1 DIY if I don't have the shop manual. I don't know where your fuel schrader is. On my 2002 it's back by the distributor