2001 4.0 SOHC all cylinder misfire

[Shaun]

Hoping someone can help. I have a 2001 ranger with 4.0 SOHC engine. Started truck mid day one day and it coughed and sputtered. Got it running but was throwing a cylinder 4 misfire. Changed the number 4 plug that didn’t clear problem. Changed wire didn’t clear problem. Changed coil didn’t clear problem but went to throwing misfire code for all 6 cylinders. Swapped old coil back in, cleared codes amd same all codes came back. Ran compression test (all plugs removed and throttle wide open for each cylinder test) highest reading was 185 lowest was 165. Leak down test is my next teat to run but i al unsure it is going to show me anything of use with the compression test being good. Does anyone have any ideas what could cause what i am seeing? I am thinking maybe timing jump but with compression good i am unsure. Could compression test show good even with timing jump? Looking for ideas here. I’ve recently rebuilt transmission and need to get this truck going again. Ill be home later this week and will be able to further diagnose.

 

[franklin2]

Been sitting around awhile? The ethanol fuel you get now loves to attract water. Condensation in the fuel tank can get into the fuel. Besides the fuel getting stale.

 

[Shaun]

Been sitting around awhile? The ethanol fuel you get now loves to attract water. Condensation in the fuel tank can get into the fuel. Besides the fuel getting stale.

No truck was driven daily before this happened.

 

[Uncle Gump]

With compression numbers like you have... I don't think a leakdown test is necessary.

So... you're getting these misfire codes. Does it run like it's missing on multiple cylinders?

 

[Shaun]

With compression numbers like you have... I don't think a leakdown test is necessary.

So... you're getting these misfire codes. Does it run like it's missing on multiple cylinders?

Yes it does run liken it’s missing for sure. The way it runs very rough coughing and sputtering. The day it happened it was running normally on the way to work and after. I was moving materials back and forth between buildings and went to start it after loading some stuff and coughed loudly out exhaust sputtered and died. I got it started after that hut running very badly mainly at idle to 1500rpm. I did drive it home that day about 60 miles. It ran ok at higher rpms but anytime had to stop for anything would have to keep throttle open a bit to keep it running in gear. I was thinking same thing about leak down test but this one has me scratching my head currently. I hadn’t considered bad fuel like suggested above as it is driven daily and this was second tank of new fuel that week. It is a possibility though. Odd thing is it started as just a cylinder 4 misfire then went to cylinder 6 and then all of them.