Popping and loss of power while accelerating

[1hvactech]

Hello,
I am new to the site and i just bought a 2000 Ford Ranger with the 3.0l vulcan. I couldn't pass this up with only 92,000 miles and for only $300 it starts and runs and the a/c works . Now here's the bad news while driving it home it had a hard time getting up to 55mph and was making a popping sound. The next day I checked the air cleaner wich was horrible, so I replaced it and cleaned the maf. Still not running better so I checked the plugs (there was a crazy mismatch of iridium and copper tops ) so I replaced all with new champion copper tops. The truck is still not running better and has no codes on my tester and cell is not on. This is a post asking for HELP I do not know a lot about this truck and any advice is greatly appreciated.

 

[RonD]

Welcome to TRS

Description could be a burnt exhaust valve.....................but, could also be "bad gas", bad gas means it has too much water in it, this will cause "popping" and low power
All gas has some water in it, but if there is too much then you get what you got, you can add a can of octane boost or HEET, these are ethanol based additives that can BOND with water(gasoline can't), this bonding allows the water to be "burned" instead of fouling the gasoline burn(misfire and popping)

Assuming no "bad gas"
Have a look at the coil pack and spark plug wires, its easy to mis-wire these
And 2000-2002 3.0l coil packs did have cracking issues

Ford uses a waste spark system, this means on a V6 that TWO spark plugs are wired to the same coil in the coil pack, both fire at the same time
These matched PAIRS of spark plugs are 1/5, 2/6, 3/4

So there are only 3 coils in the coil pack wired like this
[3 4]
[2 6]
[1 5]

So 1 2 3 on one side, BUT.........5 6 4 on the other side to match PAIRS, this side often gets mis-wired

On "most" 3.0l coil packs the 4 wire connector is between 3 and 2
Looks like this: https://www.taurusclub.com/attachments/taurus-sable-coil-firing-order-jpg.66821/

Just to "take it off the table" pull out coil pack and look for cracks, they can be small so look close, if in doubt replace coil pack
And then redo spark plug wires ONE AT A TIME, make sure they are in the correct order and in MATCHED PAIRS
Ford numbers V6 engine's cylinders this way
3 6
2 5
1 4
Front

So #4 spark plug wire goes to the coil with #3, NOT #1

After that if there is still misfires then you will need to pull out all spark plugs and then do a compression test to see if there is a valve issue

It reads like spark system has been gone thru before from your description of the mis-matched spark plugs when you got this Ranger, so this was a "known issue" by previous owner


The 3.0l Vulcan engine is a very reliable engine used by Ford from 1986 to 2008, they can take alot of miles
If there are burnt valves then it was caused by engine running lean from previous issue, or pinging/knocking issue from "bad gas" causing cylinders/exhaust valves to over heat

 

[1hvactech]

Awesome thanks for the info looks like my next step is pulling the coil pack to check it out as I have already gone through the "wonky" coil wire set up with the 123 on one side and the 564 on the other. If it ends up being valve issues do you know if I can purchase two new complete heads for this engine?

 

[RonD]

Yes, heads are available with and without valves installed

2000 3.0l Vulcan will use the 1999 and up heads and the longer head bolts which can't be reused, have to be replaced

Head gaskets need to be for Ranger 3.0l, NOT car(Taurus) 3.0l, as they are different

Look at the 8th digit in your VIN, it will be "V" or "U" this tells you if your Ranger was gasoline only or Flex Fuel model, which used different heads
V = 3.0l Flex Fuel
U = 3.0l Gas only

You can use a pair of either V or U heads, one is not better or worse that the other, the actually difference is in the computer software and fuel injector sizes
But best to match VIN