problems with chevy astro 90 4.3L 6 cylinder?

Question

i have changed 6 spark plugs, bosch plat, changed motor oil,filter, and added an upgraded air filter, K&N, my astro hesitated when going 30mph and higher,or even sometimes, when i stop and go, then in a couple of minutes, the service engine soon lights come up, can anyone please help, im also trying to upgraded parts too, and im just thinking about buying a turbo

Answer 1

When the check engine light is on you must scan it first, depending on what code is on you must diagose the problem from there, the way you describe it,it sounds like a stuck egr valve, O2 sensor or fuel pressure, you must scan the code first or your just playing a guessing game, trust me I have been a licensed mechanic for 12 years!

Answer 2

If you have a Vortec 4.3 with the CSFI or SCSFI or whatever, you'll have to pull the upper manifold off, to expose the plastic fuel injector tubes inside the manifold. Once you can see the tubes, turn the ignition key forward to the run (not start) position a few times to build fuel pressure in the system. While the fuel pump is switching on, watch the fuel tubes, and the pressure regulator inside the manifold for leaks. The tubes are prone to cracking, or sometimes the regulator will start hemorrhaging fuel.

Answer 3

If I read this correctly this is a 1990 model astro van. If that is correct we are looking at OBD ! which is a different set of diagnostic numbers.

Answer 4

adj the timing of the motor just a few degrees should take care of that problem

Answer 5

fuel filter, o2 sensor probably

Answer 6

go to auto zone ,Advance or o'reily auto parts for FREE scan...Go from there