Need some help frustrated 302 problem
#21
"Disconnected all vacuum lines from intake manifold tree and plugged. I ran a separate vac line from intake vacuum tree to fuel reg on fuel rail and to Map sensor."
From vacuum tree. Do you have power brakes? If so did you disconnect and plug the hose leading to the booster to rule out the booster diaphram as a culprit?
just a thought.
Did you check the hose from the PCV valve to the intake for cracks/leaks?
From vacuum tree. Do you have power brakes? If so did you disconnect and plug the hose leading to the booster to rule out the booster diaphram as a culprit?
just a thought.
Did you check the hose from the PCV valve to the intake for cracks/leaks?
#22
Thanks for the responses.
The idle can not be set on this truck it is EFI. Timing is set perfectly.
All Vacuum hoses have been replace including the PVC line behind the upper intake. As noted above everything is new. When changing out the cam again all new gaskets replaced.
Also no computer codes the only codes are pass test codes on eng off and eng on tests
Eng will idle if if I keep rpms above 1000, let off gas pedal the will stall, in any gear or park/neutral
Thanks
Art
The idle can not be set on this truck it is EFI. Timing is set perfectly.
All Vacuum hoses have been replace including the PVC line behind the upper intake. As noted above everything is new. When changing out the cam again all new gaskets replaced.
Also no computer codes the only codes are pass test codes on eng off and eng on tests
Eng will idle if if I keep rpms above 1000, let off gas pedal the will stall, in any gear or park/neutral
Thanks
Art
#23
Are you reusing the original throttle body? If so, did you clean the throttle bore just behind the throttle blades, where they close? Carbon will build up there and cause hesitation and stalling at idle. It only takes a small amount to cause it. I usually take a cloth with some carb cleaner and wipe it out throughly.
Check the idle voltage specs in your shop manual on the throttle position sensor. The 5.0 Mustangs had to be set just right (and could be rotated a few degrees) to get a decent idle (voltage reading). Use a modern high impedence volt meter so you won't burn out your ECU.
I'd also double check the IAC for proper operation. Considering the quality of parts coming over the counter these days, just because something is new doesn't mean it works properly.
Check the idle voltage specs in your shop manual on the throttle position sensor. The 5.0 Mustangs had to be set just right (and could be rotated a few degrees) to get a decent idle (voltage reading). Use a modern high impedence volt meter so you won't burn out your ECU.
I'd also double check the IAC for proper operation. Considering the quality of parts coming over the counter these days, just because something is new doesn't mean it works properly.
#24
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