lafitte23

I have a 93 GMC Sierra 6 cylinder 4.3L with 190,000 miles.

The truck had been running a little rough and was ready for a tune up. I changed the plugs, wires, dist. cap and rotor. The engine ran fine once I got the wires in order. I started having stalling problems after that. After stalling it was hard to start back up. I thought it was a fuel pump issue so I changed the fuel pump, screen, harness, and filter and still won't start. If I can get it to start I have to stay on the gas or it will die. Once again this started after I tuned it up. Any help would greatly be appretiated!

CP

stinemonster

I'm having some similar problems with a 93 GMC V8 5.7L except I ran mine out of gas and now it will not run.

I've changed out my Fuel Pump Relay, the diaphragm in the fuel pressure regulator and the fuel filter and none of them helped.

My next step is to change the fuel pump out but will be a couple of weeks before I get time to drop the gas tank. I'm going to check the pressure on the pump first.

Here's the link that I started with my 93 issues...

https://chevroletforum.com/forum/silverado-sierra-fullsize-pick-ups-21/need-help-truck-will-not-stay-running-23341/

If you find out the problem make sure you post it so I can try it on mine. The good thing for me is this GMC is my backup vehicle I bought when I was changing the motor out on my Silverado.

With yours, are you sure you got the rotor, wires and cap all back on right? I've learned that if I start having problems AFTER I've worked on something then I either did something wrong or I messed something up.

suzuki-guy

If it started after you changed your plug wires I would first start with checking to make sure the plug wires are in the right place!

lafitte23

I'm going through all the plug wires right now. I definitely think I did something wrong or knocked something loose during the tune up. I just pulled the O2 sensor and realized that I have never changed it since owning the truck. I will definitely change it out. I received info from an online mechanic and he thinks it may be the EGR valve or EGR controler. It started and idoled fine the last couple of days but this morning it died during idol and wouldn't restart. Could it be the MAP sensor?

suzuki-guy

Try this unplug your Egr Valve and cap the vacuum line if the problem goes away replace you EGR valve. If not do not throw parts at it!! You test the Egr valve and the solenoid with a vacuum tester. I would aim more toward what you fixed when you noticed the problem . There are three things I think could be causing this problem. 1) Timing when you changed the plug wires, cap, and rotor was your distributor loose and did you move it thus making the vehicle out of time? 2)Are the plug wires, cap, and rotor junk out of the box? I have bought a cracked distributor cap before. And I have bought junk wires before!3) Did you buy the wrong plugs with the wrong gap setting? Should be .035 I think. And if you get more get Acdelcos. Hope this helps

lukemoore646

i had this problem once on my 93 turned out to be the idle speed motor, darndest thing

in2pro

IAC Idle air control?

lukemoore646

yeah sorry idle air control