Redranger45
New Member
- Joined
- Aug 16, 2018
- Messages
- 17
- Reaction score
- 0
- Points
- 1
- Location
- Dallas tx
- Vehicle Year
- 1999
- Make / Model
- Ford
- Engine Size
- V6. 3.0 flex fuel
- Transmission
- Automatic
Rough idol on start up!
Got my truck back from the engine rebuilder. New engine. Driving home from a long drive it started misfiring badly. Took in and they check fuel injectors, said they did some rewiring on harness, sent computer off to be fixed, new plugs, new wires, put in all new gaskets. After 10 trips there I installed a new cat., downstream o2 sensors, new vacuum tubes, new IAC, new throttle body control sensor, new coil. Still misfires and rough idol for about one minute until warm then seems to run well. Today however it was misfiring badly on hwy. I have used the starter fluid test and found no vacuumed leaks that way. Plugs are new but should I check the gap? Motor craft. Brand new motor craft fuel injectors. Engine rebuilder says they checked compression and it was good. If it was an internal problem would it not be all the time? I put a fuel pressure gauge on fuel rail. Mine is a 1999 ford ranger xlt extended cab flex fuel, v6 3.0. I have listened to injectors with scope and all sound good but I probably need to listen to them when I fist start up and its running rough. Fuel pressure is 35 at key on then 57 with engine on and parked it is steady. When I cut engine off it drops to 53 holds fuel pressure for 15 minutes or longer. The regulator is in the fuel pump and there is a dampner on the fuel rail. I can change fuel filter, not sure what else to do. Hoping for some help with this. When it starts it does rev up a bit then gets rough then the idol drops.
Got my truck back from the engine rebuilder. New engine. Driving home from a long drive it started misfiring badly. Took in and they check fuel injectors, said they did some rewiring on harness, sent computer off to be fixed, new plugs, new wires, put in all new gaskets. After 10 trips there I installed a new cat., downstream o2 sensors, new vacuum tubes, new IAC, new throttle body control sensor, new coil. Still misfires and rough idol for about one minute until warm then seems to run well. Today however it was misfiring badly on hwy. I have used the starter fluid test and found no vacuumed leaks that way. Plugs are new but should I check the gap? Motor craft. Brand new motor craft fuel injectors. Engine rebuilder says they checked compression and it was good. If it was an internal problem would it not be all the time? I put a fuel pressure gauge on fuel rail. Mine is a 1999 ford ranger xlt extended cab flex fuel, v6 3.0. I have listened to injectors with scope and all sound good but I probably need to listen to them when I fist start up and its running rough. Fuel pressure is 35 at key on then 57 with engine on and parked it is steady. When I cut engine off it drops to 53 holds fuel pressure for 15 minutes or longer. The regulator is in the fuel pump and there is a dampner on the fuel rail. I can change fuel filter, not sure what else to do. Hoping for some help with this. When it starts it does rev up a bit then gets rough then the idol drops.
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