I have a 1989 chevy g20 conversion van and i was driving it through the drive thru and it just died. it won''t restart. i have taken the dog housing off and can see the throttle body is getting fuel. i have also checked the spark from the coil to the cap, and it looks like it''s getting good spark. i removed the cap and appears very dirty, could my dist cap and rotor be the problem?
Chevrolet G20 Van 305Already Tried: cleaned cap and rotor, checked for fuel at throttle body, checked for spark from coil to dist cap
If the spark is nice and blue, there is fuel pressure to the throttle body but no spray it could be the ignition module or engine control module. The fuel pressure should be 9-13 psi to the throttle body. These distributors corrode and crumble at the magnet and pole piece causing an erratic or distorted signal for the pickup coil which sends the signal to the ignition module which in turn controls spark and fuel delivery/timing. If severe enough it's possible you could have a spark (although it may be weaker than it needs to be) but no fuel control for the injectors (the engine control module grounds the injectors based on the signal sent from the ignition module). If the dsitributor is suspect replace with a new one (will come with new ignition module and pickup coil), new cap and rotor, time and retest.
Reply to Dan's Post: when you say "spray" at the throttle body what do you mean? as i see fuel pouring onto the closed "butterfly"? valves. how do i check fuel pressure? thanks.
The injectors "spray" into the throttle body when cranking and running the engine. The fuel pressure is tested by removing the fuel filter, install an adaptor in place of the filter and connect the fuel pressure gage to the adaptor. These tools can be found at your local autoparts store. If there's fuel out the injectors then verify the spark is a nice blue one and at more than one cylinder. It's possible you have spark but it's not hot enough either from a weak ignition coil or faulty distributor and components (pickup coil, ignition module, cap and rotor, pole piece, magnet). Also check the plugs and make sure they aren't fouled if you are getting fuel with no or weak spark that may gas soak the plugs.