Q: Rough idle and stalling after coming off the highway.

asked by on February 21, 2017

The sub is a 350 TBI, it idles rough, almost like it's running out of fuel and coming off lights it will stall out. Then when I let it sit for a day it drives great and only idles rough. New parts: Fuel pump, fuel filter, EGR valve, radiator, water pump, temp sensor, starter, fuel relay, distributor, cap, rotor, wires, plugs. I'm replacing the EGR solenoid on the first. Any info helps.

My car has 340000 miles.
My car has an automatic transmission.

Hi there. Sometimes the best fix is the simplest solution. On you list of things you have completed, what is missing is cleaning fuel injectors and the throttle body. Typically idle issues and stalling after frequent fuel delivery (like on a highway) is caused by a restriction of fuel or problems atomizing the fuel; which is the duty of the fuel injectors and to a point, the throttle body. I would recommend replacing the EGR solenoid, but also take time to professionally clean the throttle body and fuel injectors. Perhaps replacing the fuel injectors is a better solution depending on whether this has ever been done on a vehicle more than 20 years old.

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