My 95 chevy Tahoe wont stay started after I installed a water pump

Check fuse and power to the fuel pump relay. If your oil pressure sensor reads too low, it might start but won't stay running. Good luck.

Could be the water pump leaking.

could be fuel pump or even crank or cam , timing sensor. Did it start running strange before this?

If you are sure you have normal coolant flow thru the radiator, the only thing you mentioned that might be different is the manifold. Its possible you don't have all of the water jacket outlets matching the passages in the intake for cross flow.

The injectors can't be spraying good or it would start. What is the fuel pressure reading?

You've already eliminated #3 and #6, so keep checking...

Priority Action Part Type Cause
1 Inspect Radiator Cooling System Clogged.
2 Inspect Radiator Radiator Fins Obstructed.
3 Inspect Radiator Cap Worn or Damaged Radiator Cap.
4 Inspect Radiator Fan Motor Faulty Fan Motor.
5 Inspect Belt Incorrectly Routed, Adjusted (Tensioned), Missing or Worn Drive Belt(s).
6 Inspect Thermostat Faulty Thermostat.
7 Inspect Water Pump Worn, Cracked or Leaking Water Pump.
8 Inspect Radiator Fan Relay Intermittent Failure

did you install the oil pressure switch origional to the tahoe? The tahoe uses a low oil pressure shutdown, instead of an inertia switch to shut off the fuel pump in the event of an accident. If the pressure circuit does not close within 3 seconds after the engine starts the fuel pump shuts off. This is in case the truck is on its side or upside down the pump will shut off.

Is the check engine light on? If so, rent a scanner and read any code(s). Follow the clues to repairs. Does the fuel pump continue to run? It should only run for a short time at key-on, then shut off after building pressure. Likely, new pump time. It wouldn't hurt to install a new fuel filter as well if not already recently replaced.

If it has injectors it has a ecu, if it has an ecu it has a diagnostic port (normally under the drivers/passenger dash) if you look down at seat botton level you should see a small black port) You can go to any auto zone or parts place and they will scan it for free. You may have a head gasket issue with overheating or your cooling fan(s) may not be turning on. Check the codes first

hi i have a 1997 chevy tahoe that starts but won't stay running i have changed fuel pump, fuel filter,relay ,spark plugs, and just changed rotor and dis. cap ready need some help to figure this out please.