cold run problem
#1
01-16-2005, 02:13 PM
cold run problem
maybe you could tell me where to start looking. I have a '99 ranger 3.0L V6 w/75k. I bought the truck w/32k on it. The only maint has been oil changes, and lucas fuel additive to alleviate spark knock. (works well for me). It has been a trouble free rig.
The problem I'm having is intermittent but always on cold start. When it does occur it may take a couple of attempts to get it to fire off. I can hear the fuel pump run and shut off and assume pressure is ok. I have to use throttle on occassion and then throttle to keep it running. If it returns to idle it dies. Restart then is hard, long crank and have to clear it out. Just like you would an unchoked carburated rig. I've noticed a chemical oder in the exhaust when its doing this too. Like enamal smells. The high idle usually present on cold start up isn't there. Then when it is running and I'm down the road a bit, running smooth and all, the truck sometimes gets a boost of guts like I mashed the throttle when I didn't. That alone is so dang fun it's almost worth the problem
All this might happen all or in part for a couple days then goes away for a week or so???
Thanks
Scotchme2 (oh oh where's spellcheck?)
The problem I'm having is intermittent but always on cold start. When it does occur it may take a couple of attempts to get it to fire off. I can hear the fuel pump run and shut off and assume pressure is ok. I have to use throttle on occassion and then throttle to keep it running. If it returns to idle it dies. Restart then is hard, long crank and have to clear it out. Just like you would an unchoked carburated rig. I've noticed a chemical oder in the exhaust when its doing this too. Like enamal smells. The high idle usually present on cold start up isn't there. Then when it is running and I'm down the road a bit, running smooth and all, the truck sometimes gets a boost of guts like I mashed the throttle when I didn't. That alone is so dang fun it's almost worth the problem
All this might happen all or in part for a couple days then goes away for a week or so???
Thanks
Scotchme2 (oh oh where's spellcheck?)
#2
01-16-2005, 06:27 PM
Welcome to FTE! Is your 3.0L a flex fuel (VIN 8th digit a "V")?
The starting difficulties make me think it's a fuel issue and/or a problem with the Idle Air Control (IAC) valve. Because of the surging while your driving down the road, I'm more inclined to think it's fuel-related. So I guess I'd start there. You really should try and track down a fuel pressure gauge and check the fuel pressure: Fuel Pressure Testing
If it's never been changed to your knowledge, you should think about replacing the fuel filter.
The IAC is critical to starting, not just idle. Note that by pressing the pedal to the floor while cranking, you are only introducing more air into the system, not fuel. In Ford EFI systems, the fuel injectors are cut off while cranking at WOT, almost like a "reverse choke".
Also, I recommend you at least look over the things mentioned in this TSB: Technical Service Bulletin 00-5-4
See also: https://www.ford-trucks.com/forums/s...d.php?t=315257
The starting difficulties make me think it's a fuel issue and/or a problem with the Idle Air Control (IAC) valve. Because of the surging while your driving down the road, I'm more inclined to think it's fuel-related. So I guess I'd start there. You really should try and track down a fuel pressure gauge and check the fuel pressure: Fuel Pressure Testing
If it's never been changed to your knowledge, you should think about replacing the fuel filter.
The IAC is critical to starting, not just idle. Note that by pressing the pedal to the floor while cranking, you are only introducing more air into the system, not fuel. In Ford EFI systems, the fuel injectors are cut off while cranking at WOT, almost like a "reverse choke".
Also, I recommend you at least look over the things mentioned in this TSB: Technical Service Bulletin 00-5-4
See also: https://www.ford-trucks.com/forums/s...d.php?t=315257
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