Cause of 1994 s10 blazer losing spark

I have a 94 chevy s10 blazer 4dr 4x4 with the 4.3L TBI vin w. It has suddenly lost spark. What would cause it to do so? We have replaced the coil and spark plugs but still appear to have no spark. What should we check or replace next please let me know asap thank you

I have a 94 chevy s10 blazer 4dr 4x4 with the 4.3L TBI vin w. It has suddenly lost spark. What would cause it to do so? We have replaced the coil and spark plugs but still appear to have no spark. What should we check or replace next please let me know asap thank you

Where are you checking for lose of spark?
At plugs or right out of coil?

Is it the old style dist or new flat top dist?

Is dist shaft and rotor turning when cranking engine?

Any codes?

HAve you checked the ignition control module, under the cap? They can be tested, before changing them.

Probably a weak fuel pump. Before you start the car turn off the fan, radio and anything else that will make noise. Close the door and roll the window down ( this keeps the door buzzer quiet) and turn the key to "on" being careful not to engage the starter and listen. You should hear a low growling sound coming from under the car in the gas tank. it will only make the noise for a few seconds so listen closely. If you do hear it the fuel pump is working and you should probably change the fuel filter and make sure the fuel lines are not cramped. Also ( in the believe it or not category) make sure the fuel cap is on and you hear three clicks when you tighten it. If you don't the fuel tank won't pressurize properly. Good luck.

Probably a weak fuel pump. Before you start the car turn off the fan, radio and anything else that will make noise. Close the door and roll the window down ( this keeps the door buzzer quiet) and turn the key to "on" being careful not to engage the starter and listen. You should hear a low growling sound coming from under the car in the gas tank. it will only make the noise for a few seconds so listen closely. If you do hear it the fuel pump is working and you should probably change the fuel filter and make sure the fuel lines are not cramped. Also ( in the believe it or not category) make sure the fuel cap is on and you hear three clicks when you tighten it. If you don't the fuel tank won't pressurize properly. Good luck.


Why is it you think a weak fuel pump will have an effect so that he has no spark?

haha

if it has no distributor, check ignition control module under coil packs.