Pontiac Repair: pontiac transport, fuel pump relay, pontiac transport

Question
HI, I have a 94 Pontiac Transport and it had been acting up starting with dying out while driving the gauges acting crazy while driving although the van was running good. Finally it got to where it would not crank up just turning over. I thought it was the fuel pump, so I changed it and the fuel pump relay. It still gave me a hard time trying to crank but as long as I was spraying in ether where the air filter is it would fire right up and run until the ether stopped. Then it got to where it would finally fire on its own and I actually drove it for about 15 minutes until it died again. Now it cranks when it wants to and then it will die. I thought it was my crank sensor going bad but then I was told it was my cam sensor. What is your opinion on this? I want to sell it but I want to sell it in running condition. Thanks in advance.

Answer
Hi Lamar:

well you need to check a few things It must have spark because it is running on the spray. So I would maybe rule out a crank sensor that sensor is the trigger for bith spark and fuel control It could be partially failed? I would check the fuel pump pressure it should be between 35-40 psi when you turn the key to run for a prime and then run again while you crank it over. Next you need a noid light or an Engine computer friendly test light and see if it has injector pulse unplug an injector and crank the van the lamp should flash on ever injetor that the lamp it plugged into. If not then it's possably the engien computer id get getting the engine crank signal. that siganl is created by the ignition module and that module creats the signal from the crank sensor. So they are all inter connected. With out seeing it It's hard to say what the culprit here is. As for the no crank issue it may or may not be related when you crank the van over and it will not crank check the purple "crank" feed at the starter with a 12Volt test light that light should light when ever the key is in the crank psoition if not You could have a bad ignition switch or a bad park safety switch on the transmission. I would also check all you ground wires at the battery and the body and at the engine block especially the ones under the ignition module. good luck :)