Hey Folks,
Really in need for some expert help orexperience with my 94 S10 4.3 Vortec (W) engine code. Recently ran into some problems with the motor dying out on me after driving for about 15 min. or so. It runs fine then all of a sudden I go to give it gas and it falls on it's face and stalls. Sometimes I can get it started and idleing but if I try to go anywhere it immediately dies. The more I try then it stops starting all together.

Within the past couple of days I've replaced the Fuel pump, Sending unit, "Nut Kit", Spider injector, and injector harness. Installed new upper plenum gasket also.

Within the past year I've replaced the distributor cap and rotor and wires along with the fuel filter.

With the fuel system basically new I'm some what stumped as to what it can be. I have a scan tool and there are no thrown codes to be found.

Could it be a sensor of some kind? Or maybe the coil (I think I replaced that recently too). Is it possible it's oil pressure related? Just asking as I have no reason to think the cars oil pressure is dropping. Alternator dying out?

The funny thing is if I let it sit for a little while and it cools off it starts right back up. As per scan tool the vehicle is definately going into closed loop way before any of this happens. It's almost as if something is heating up to the point of malfunction.

Same symptoms from before and after the work was completed.

Any help would be so appreciated. Hopefully someone else has experienced thisand found the cure.

Thanks in advance.
Rob

 

I have a suspicion of either the coil or module-just a thought. I'm sure someone oelse will chime in. Jerry[]

 

I would suspect an ignition problem as well. I would remove the coil and the ignition control module and take them in to Autozone, Advanced, etc and have them tested. Test them both repeatedly (10+ times) in rapid succession to get them hot.

 

You might check the EGR Valve. It is a sensor for emissions. It sometimes gets stopped up with carbon from the engine and exhaust. Mine did the same thing one or two times. I had it cleaned out, then when it did it again, I had it cleaned and had a small piece of screen installed over the hole. It prevents the carbon pieces from stopping up the valve. Try putting some Seafoam engine cleaner into the fuel tank. You can buy this product at Advance Auto or any local auto parts store. If that doesn't help, you might have to have the valve cleaned, or have a piece of screen put on it.

 

Thanks everyone. One of my first thoughts was possibly the coil (didn't think about the module). My father in law who is somewhat knowledgable with cars felt in his experience that when a coil went bad it goes completely bad ( not intermittent - start sometimes not others). He didn't even think about the module either.I will remove both the coil and module and bring them down to autozone to have them tested for sure.

BigE - as for your advice on the EGR valve. I forgot to mention in the original post that this was one of the repairs made over the past few days. EGR is functioning properly and a screened gasket was indeed installed. Thank you.

Thanks again everyone.

I will get to the bottom of this.

Rob

 

Could the fuel pump relay have anything to do with my problems? BTW, haven't checked the coil or coil module yet.
Thanks.
Rob

 

sort of doubt it but the next time it quits, pull over key off for ten seconds and then key it on-if you hear the pump prime for two seconds...I doubt it is the relay. You could also swap it with another same relay on your firewall-I believe near your tranny dipstick if memory serves me correct.(think it to be there along with another same # relay)

 

94 the fuel pump relay and its neighbor are beside the master cylinder/booster for the brakes on the firewall like so:

pic was taken on my 94

 

just wanted to say thank you to all who gave some insight. I changed out the coil and coil wound up purchasing a (new) remanufactured distributorand to this point seemed to have done the trick. To not get stuck too far away from my home I let it idle for about 10-15 min in the driveway. I then took it for a 15-20 min drive around the neighborhood. I then let it sit for about another 10 min idling in the driveway and then lastly took it for another 10 minute drive. Not a problem so hopefully that fixes it.

One last question for you guys. I marked the old distributor location with regard to therotor (where it was facing) and gave myself a landmark with the base of the old dist. in relation to the plenum. When I stabbed the new dist. I got it pretty much right on to where the old one was. Pretty close is not good enough for me though. Truck is running pretty well but seems to be lacking a little power. I want to set the base ignition timing to the specified 0 degrees. I've read the label under the hood and know there is a wire that needs to be disconnected in the passenger compartment to remove the advance.

My questions are 1. Where is the wire located in the truck? 2. What is the easiest way to be able to view the timing tab and crank pulley? I gave it a quick look today and there just seems to be so much stuff in the way. Any help would be appreciated.

Thanks.
Rob

 

Wire should be inside the truck just under the passenger side carpet near the transmission hump.

As far as viewing the timing tab, it is fun. You do not happen to be a contortionist do you? You could remove the upper fan shroud and remove the fan/clutch assembly. This should give you a pretty good view of the balancer and the timing tab.