About Van Expertise I have been maintaining a fleet of approximately 55 light, medium and heavy vehicles for over 20 years. Most are 4X4 pickups and off road fire fighting trucks. Some medium duty trucks. Some military light trucks.
I can answer most questions concerning 4X4 engine, drive line, suspension, electrical, and fuel, both diesel and gasoline. Ford, GM, and Dodge, old and new, but prefferably not newer than 99.
Question i have a 1998 s-10 blazer my question is how do i know if the fuel pump is bad or some thing else i started having problems starting it especialy when cold then nothing i replaced the pressure regulator witch was a job since i had to remove the t-b cover ( oh its a csefi system)now i just got a pressure gague and when i first turn on the pressure goes to about 42psi as the pump wines then i here the relay click and the pressure drops to 0 as i turn off the key it again will go up to 35pai and then drop to 0 since i dont have the ideal location to drop a gas tank and the shop wants $700-850 to put one in i want to see if there is anything else i should check thank you for your support
Answer Hi Bob,
Sounds like your pump is working correctly. It should, however, stay at the 35 to 45 PSI reading if you are cranking the engine over, or if it is running.
But as soon as the engine quits rotating, it will shut the fuel pump off.
If your pump doesn't continue running, it could be the crank sensor, which signals the ECM that the engine is probably running, and keeps the fuel pump relay engaged.
The crank sensor also effects the injector control.
Have you checked for power to the injectors, and then check por pulses at the injectors while cranking.
You may need to get a "noid" light.
But I wouldn't be dropping the tank according to what you tell me. I would look for spark, and injector operating.
