My 2001 Ford Ranger Gas 3.0 6 cy died/Blown heads melted piston, Found a 3.0 6 cy flex fuel, I swapped the upper intake plenum, water pump, sensors, and kept the original wiring harness from truck and swapped the fuel rails, truck will not idle with gas spark plugs but will with the ff plugs. Do i need to swap the lower intake? or the Heads as i know there is a compression diiference in the two engines. Any help would be great before I start tearing the engine apart, it is misfiring, and back firing into the throttle body/air cleaner, I stuck here. New to this flex fuel stuff.
Thanks,
Warrior Angel

 

It's a little hard to follow exactly what parts combination you ended up with. Are you using FFV injectors with the gasoline PCM? If so, then that is at least part of the problem.

 

no, truck was gasoline, but am using a ff engine, i did swap the fuel injectors and fuel rail, as well as the upper intake plenum. I am trying to keep the truck gasoline, do not want it to be flex fuel

 

Is the large air tube connected and leak free between the MAF sensor and throttle body? Mass air EFI will run very poorly without the tube. How about possible manifold vacuum leaks?

When you say "swap", do you mean swap original parts from your truck onto the replacement engine or do you mean swap FFV parts into your Ranger?

 

i took parts from the original engine and put on the replacement engine, I am wondering about knock sensor, I believe the flex fuel engine which is out of a 2004 had one, but don't recall the original 2001 gas engine having one,
If I remember correctly, there was no hook up for it with the original wire harness. Would you know if there was a knock sensor on the 01 gas or 04 flex fuel.

 

I have done this swap many times with no problems. One thing that always seems confusing(for some reason) it the firing order. I would check it and go by the coil. There are marks by each tower for each cylinder.

 

Ive done that 3 times already, and it is the way it is suppose to be. no vaccuum leaks, all sensors connected and working, no cel's. Im stuck, it's like the timing is off, and it acts like it is flooding out,

 

Try unplugging you MAF sensor and see if it runs better, I've seen those cause idling problems.

 

can i take the original 2004 flex fuel engine and its wire harness and plug it into the pcm and just have it be flex fuel without any problems

 

I've never tried that but I don't think it will work.

 

already tried that, and it did not, so that is working, cleaned and checked the iac and iat, all fine, injectors clean and working, fuel pressure at 60 and holds. have spark and fuel, engine starts and idles with flex fuel plugs, with gas, it starts first time after they are in, but will not start second time, like they are flooded.
my brain has been going around the clock trying to figure this out. I do have a sensor, which appears to be a knock sensor that was on the flex fuel engine, but there was not one on the gas engine.
Is it possible that 2001 gas did not use one, but the 2004 flex fuel did?

 

The last year for the 3.0 Ranger FFV was 2003. The knock sensor doesn't have any influence until the engine is under load and, even then, its effect is subtle unless really bad fuel is being used.

The 2001 3.0L didn't have a knock sensor so there's no way to wire one in using the original 2001 harness and PCM. Some other year 3.0's were equipped with a knock sensor but if one is present on the replacement engine, it won't help or hurt anything.

 

Yeah a flex fuel motor will have one. When running on ethanol the timing gets adjusted. The computer gets a signal from the fuel compensation sensor telling it when your running flex fuel. Because the fuel mixture can change the timing adjusts any time it senses a change or a spark knock. Could be something stupid like a bent pin in the engine harness plug or a stuck injector. Get it running and pull the plug wires off one at a time to see if you can figure out which plug or plugs are causing the problem...I'm betting the drivers side...

 

it won't rev past 3000 rpms without trying to die, took it for a drive and has no power, is it possible that the flex engine has a different firing order than the gas engine

 

I think they are the same but I would verify it to be sure and go by the coils markings because I have seen a misprint in a Haynes manual.

 

Have you tried disconnecting the cats? One or more may have melted during the catastrophic engine failure and pieces of the molten substrate usually go downstream and plug either the next cat in line or the muffler.

 

thanks I checked that, as I am going by the Haynes manual 1-4-2-5-3-6, and the book i have is the correct way, going by the coil pack, so that is correct..1-1, 2-2, 3-3, 4-6,6-5,5-4,

 

well any other ideas, would be greatly appreciated, I need to go offline, but please feel free to leave more posts, or if you are up to talking on a phone, and if it is allowed on here, my number is 952-686-8359. I need to get this figured out soon, as I will be leaving town for work soon and wont be able to work on it till winter,
Thanks

 

Did you ever have any luck with this?

 

I was wondering the same thing. I know the flex fuel system runs about 58 pounds of pressure, I don't think the regular engine runs that high.. I also know, the regular injectors won't work on the flex fuel system. I'd bet he needed a fuel pump, or use the other injectors.

?

 

On on 2001 3.0 the lower intake is different. It is the only year that they had a different lower air intake from1998 to 2010. I a female, changed the lower intake and it ran like a brand new engine. It alreadt has 20,000 miles on it since i swaped it out for my man who don't work on cars/trucks.