So i have this problem with my 05 ranger 4.0, did the timing job with the special tool, i went for the first start it runs rough then after a while it smooths out but if you try to give it gas it wants to die. i’ve got P0320 code. after going through a forum i’ve read that the coyles kit has a thinner crankshaft sprocket which cause the harmonic balancer to go more in which moves the tone ring away from crank sensor. wondering if anybody has experience this before

 

EDIT: You were exactly right. The crank sprocket/gear that came with my kit was made for a 4.0 with a completely different harmonic balancer. You can either swap crank sprocket/gear from the kit with your old one or find an old style harmonic balancer. I changed harmonic balancers and it completely fixed mine. 110% what my problem was… I tore this engine apart 3 times and reset the timing, the last time I completely removed the heads and checked each valve. The crankshaft gear is .003” thinner than the gear that came on my truck. That’s just enough to move the harmonic balancer closer to the engine and AWAY from the crankshaft sensor. The P0320 code was because of the sensor not getting an accurate reading on the different style tone ring. The sensor wasn’t bad, therefor changing it didn’t help… that really throws you for a loop haha. Hopefully anyone with the same problem finds this thread and this helps.

Hey, I have the SAME exact problem. I’ve read a few people’s post where they also had the same problem but what you just described with the crankshaft sprocket is the first I’ve heard of it. I’ve tried everything. I bought a cheaper timing chain kit so it’s very possible I have a problem with the sprocket considering I have the same code.. P0320. I pulled the heads and checked the valves and there’s nothing wrong with them. I’ve checked the timing on the motor 3 different times now with a tool I bought off Amazon. I’ve watched multiple YouTube videos and did the job exactly as they did so I couldn’t figure out why I’m having this problem when there was nothing wrong with it before the timing chain replacement. The truck ran nearly perfect after the timing chain replacement until I noticed a bit of hesitation around 3k rpms and then the P0320 code popped up. I changed the crankshaft position sensor and camshaft position sensor and nothing. The hesitation/missfire gradually got worse until it wouldn’t even move under it own power and eventually stalling when giving it throttle past 800 rpm’s. (This was over the course of 2 weeks) It smells really strong of unburnt fuel when running and the spark plugs are black. I’ve tried everything and what you’ve explained seems the most likely (I’m hoping that’s the problem). I’m so close to giving up. I’m going to try to get an OEM crankshaft sprocket and compare it to the one from the kit as I have the truck tore apart for the 3rd time lol. Please let me know if you learn anything else, I would love to know haha.