chico3371

Have a 92 Astro AWD that idles very good but once you put it on gear it wants to stall did a tune-up and still doing the same thing any ideas

old_master

What parts were replaced during the tune up? What brand of spark plugs did you use? Is the check engine light on? Did you check for vacuum leaks? How many miles are on the vehicle?

chico3371

Bosh plugs new wires cap and rotor, did check for vacuum leaks did not hear any, check engine light comes on after a wile and it has around 135,000 miles somebody said it could be the Idle Air Control could that be possible

old_master

The 4.3L engine is very sensitive to the brand of spark plugs that are used in it. AC Delco double platinum plugs are recommended by the manufacturer, and you will get the best performance when using them. There is something about the crossover with other plug manufacturers and they can't seem to get it right. As a result, the engine runs poorly. I realize it's a lot of work and money to replace them, but the engine will run better using the AC plugs, guaranteed. When the check engine light comes on, what code(s) is it storing? Auto Zone and Advance Auto will check it at no charge for you. The Idle Air Controller, (IAC) could be causing the stalling problem. The IAC is a computer output and may or may not cause the check engine light to come on, might be worth a try. Another possibility is that the EGR valve may have carbon in it not allowing the pintle to close completely. The valve can be removed and cleaned out very easily. Hope this helps.