Newly acquired 2002 Ford Ranger 4.0 liter 6 cylinder. Motor has been freshly rebuilt. The motor only has 230 miles on it. I have been driving like Miss Daisy. Recently when I step on the gas to accelerate the truck has a slight jerk and hesitation. It levels out after I reached the desired speed. I am wondering if it’s a fuel or spark problem. First ranger I have ever owned. Very nice truck. Just need help with the troubleshoot. Please help

 

Welcome to the forum

Not much to go on
Yes, could be spark or fuel, lol

Clean MAF sensor, should do this every year

I assume the CEL(check engine light) works, should come on with key on and then go off after engine starts
You can get the codes read at almost any auto parts store, free, WRITE DOWN any codes in memory

Get PDF owners manual here: https://www.ranger-forums.com/genera...1-models-3747/

Does the bucking happen when engine is cold and warm or just one or the other?

 

The check engine light is on. The motor does the hesitation and jerking whether it’s cold or warm. Gonna check fuel system and spark plugs to start. Not sure where to start though

 

GET THE CODES!!!!

WRITE THEM DOWN

That will tell you where to start

Post them here

 

P 0174 and P 0301. It’s showing a few B codes which are the airbag system. The P0174 is MAS and P0301 is a cylinder 1 misfire

 

How to I fix and diagnose the misfire

 

am having similar issue just no check engine no codes

 

Please start your own thread if you want help with yours, otherwise this thread will get to confusing.

EDIT: I didn't realize you started 3 other threads for the same problem.

 

P0301 Cylinder 1 Misfire Detected
P0174 System too Lean (Bank 2)

Those are odd codes to have together on a V6 engine

An O2 sensor can only "see" oxygen in the exhaust, P0174 means drivers side(Bank 2) exhaust is showing too much oxygen

P0301 is a misfire on Bank 1, the passenger side of a V6 engine

A misfire means no Oxygen was burned in cylinder 1, because it didn't ignite(fire) so that oxygen would be dumped into the exhaust manifold where that sides O2 sensor would '"see" it
So I would expect P0171 System too Lean (Bank 1) with P0301

The jerking is the misfire so thats the first thing to fix
Pull out spark plug on #1 and have a look
You may want to swap it with #2 spark to see if code changes to P0302, meaning that spark plug is bad

Clean MAF sensor regardless

 

Changed all spark plugs. Now the motor stalled out on me 3 times going around the block. New plugs, new MAS. What else do I check or replace

 

Didn't need to change spark plugs, just needed to look at the tips

So what did the old spark plug tips look like?
Look here: https://www.freeasestudyguides.com/g...park-plugs.png

And here: https://live.staticflickr.com/2077/1...720b789e_b.jpg