Hard To Start When Cold Outside
#13
I don't think so. I completely removed the quick connect fitting from the filter (outgoing side) and attached the pressure gauge to that side of the filter with the quick connect line hanging down.
#14
Only replaced the fuel filter. checked a few plugs and they looked good. also check spark with a tester and had good spark. I am still planning on doing plugs and wires but im kind of stuck on the fuel delivery issue now.
#15
Perfect!
This quote is from post #8:
"Checking fuel pressure at the service port indicates regulated pressure or maximum pump output pressure, whichever is LOWER. This is why the pressure needs to be checked at the filter... to make sure the pump can supply enough pressure to satisfy the regulator."
The pressure reading you got of 55psi is all the pump can supply to the injectors and regulator, and it's about half of what it needs to be. The regulator was not being satisfied so it wasn't / isn't bypassing, (regulating) any fuel. It's also why the engine runs poorly. This is a perfect example of why it's so important to check "dead head" pressure.
Now you need to drop the tank down far enough to unplug the module connector so you can check voltage on the grey wire during pump prime. Needs to show battery voltage. Then check resistance on both black wires to ground. Must be less than 5 ohms. If voltage & resistance are OK, drop the tank and remove the fuel pump module. On the top of the pump motor there is a 3/8" flex hose that runs up to the module housing. There is a clamp on each end, make sure they're tight nd that there are no cracks in the line. Post your results.
This quote is from post #8:
"Checking fuel pressure at the service port indicates regulated pressure or maximum pump output pressure, whichever is LOWER. This is why the pressure needs to be checked at the filter... to make sure the pump can supply enough pressure to satisfy the regulator."
The pressure reading you got of 55psi is all the pump can supply to the injectors and regulator, and it's about half of what it needs to be. The regulator was not being satisfied so it wasn't / isn't bypassing, (regulating) any fuel. It's also why the engine runs poorly. This is a perfect example of why it's so important to check "dead head" pressure.
Now you need to drop the tank down far enough to unplug the module connector so you can check voltage on the grey wire during pump prime. Needs to show battery voltage. Then check resistance on both black wires to ground. Must be less than 5 ohms. If voltage & resistance are OK, drop the tank and remove the fuel pump module. On the top of the pump motor there is a 3/8" flex hose that runs up to the module housing. There is a clamp on each end, make sure they're tight nd that there are no cracks in the line. Post your results.
#16
Did all checks with ok results, so I went ahead and put in a new fuel pump. After reassembly she started right up. Thanks for all the advice and useful info in diagnosing problem. Very much appreciated.
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