Questions and Answers

GMC Vandura G-2500 Dead Spot Q. Hi, I have a 1992 GMC Vandura G-2500, 4.3 liter V-6. It has 300,000 miles on it and I recently replaced the engine. Most emission components are original. It has a dead spot or hesitation in it. It has new injectors, a somewhat good fuel pressure regulator and a new TPS. So, is it time to replace the fuel pump, pressure regulator, MAP sensor, distributor pickup, and EGR?

Can these be doing all of this at once? The new TPS made the big difference; most all the components have 100,000 miles on them, others 300,000 miles. Any close ideas?

A. First thing to do is to remove the vacuum line from the EGR valve and plug it with a golf tee to see if your problem is gone. I've seen a lot of these EGR valves open too much, too soon causing a hesitation. If it stops, replace the EGR valve.