Hey folks,

Truck was running rough yesterday and CEL came on as I was just about home. I looked this morning and get misfire codes for the 1,2 and 3 cylinders as noted. Where do I go from here? Seems unusual for them to all go at the same time?
For what it's worth, I had the A/C compressor and accumulator replaced last week - is it possible something was knocked loose then?

 

2001 Ranger would have the 4.0l SOHC engine

Any rattling noises from timing chains?

Ford uses a Waste spark system, with 3 coils in the coil pack, so TWO spark plugs fire at the same time
1 5
2 6
3 4
Are the matched sets so if spark on #1 failed then spark on #5 would fail as well
So not a spark issue, you can check that 1, 2, and 3 spark plug wires are pushed down all the way in coil pack

1, 2, 3 fuel injectors share the same fuel rail on passenger side, but a longshot that pressure dropped just on that one bank, since both banks are feed by the one fuel line from the pump, not impossible just a longshot and I would expect Lean codes preceding something like that.
Same for a vacuum leak on that bank, Lean codes would come up before mis-fires

Over head cam(OHC) on that bank may have slipped on timing chain, have to do a compression test to see if that happened
OHC effects all 3 cylinders on a bank at the same time

No, can't see any A/C work causing this problem, no real common link for wiring or vacuum lines that would effect just one bank

 

Thanks for the input although not what I wanted to hear. Guess that makes another project for me.

 

Dang, I'm getting about 60 pounds in those cylinders - meaning the timing chain has taken a dump.
Anyone have suggestions for repair place in LA county/Inland Empire area?

 

Try YELP for your area, they have reviews

"Best Ford Mechanic" search for LA seen here: https://www.yelp.ca/search?find_desc...+Angeles%2C+CA

 

Hello I had this same problem with my 4.0 and the timing chain had jumped a link. This is the dreaded rear chain that would require engine removal for replacement.
I was able to make it jump one link by removing the mechanical tensioner from the side of the engine to give the chain maximum slack, and then with a screwdriver under the chain, I rotated the engine carefully. There was enough slack to allow the chain to raise and move one link. Still working fine after several years. I entered a post on this site about this problem. Only had to remove the valve cover, and un-thread the tensioner.