1997 4.0 Backfiring

[Theroux1113]

Have an issue with my ranger backfiring. Fuel economy dropped, as well as it backfires when going up steep hills and when I drive on highway. Sometimes doesn’t backfire but jerks violently. Any suggestions? Needs other work that I was about to do but if it’s a timing chain I’m not even gonna bother. Looks like there’s an oil leak coming from front of engine as well if that has anything to do with it

 

[RonD]

Welcome to TRS

1990-2000 Ranger used the 4.0l OHV engine so no timing chain issues
2001-2011 Rangers used the 4.0l SOHC engine, it could have timing chain issues

How old are the O2 sensors?
They last 12 years or 100k miles, ONLY sensors that wear out on a schedule
Old O2's will cause Rich running after they pass their prime, and NOT set a code

Clean MAF sensor, once a year, its easy

Backfire means a cylinder misfired so all the fuel was not used up and it is dumped into the hot exhaust system where it ignites with a "pop" noise
So change spark plugs if they are do, to maybe get rid of misfires
Gap is big, 0.054"

Spark plug wires last 10-12 years or so

Oil leak at the front shouldn't cause a running issue but you need to find the source, could be oil pan gasket but might be front main seal, the later will leak a lot more than oil pan leak, i.e. not just drips

 

[Theroux1113]

Welcome to TRS

1990-2000 Ranger used the 4.0l OHV engine so no timing chain issues
2001-2011 Rangers used the 4.0l SOHC engine, it could have timing chain issues

How old are the O2 sensors?
They last 12 years or 100k miles, ONLY sensors that wear out on a schedule
Old O2's will cause Rich running after they pass their prime, and NOT set a code

Clean MAF sensor, once a year, its easy

Backfire means a cylinder misfired so all the fuel was not used up and it is dumped into the hot exhaust system where it ignites with a "pop" noise
So change spark plugs if they are do, to maybe get rid of misfires
Gap is big, 0.054"

Spark plug wires last 10-12 years or so

Oil leak at the front shouldn't cause a running issue but you need to find the source, could be oil pan gasket but might be front main seal, the later will leak a lot more than oil pan leak, i.e. not just drips

Thank you!! I am pretty sure the plugs have been done recently as the wires definitely have. Will check regardless though when I get down to it. While I have you here, another question. I have to do a lot of work to this truck including the exhaust. What years exhaust will fit on my 97?? I have someone I am going to uni with with an 05 that just had her engine blow and I was thinking about taking the exhaust. Will it work with the bolt on just below the manifold and before the cat? I just want a straight bolt on as I’m not a welder and don’t have access to one. Thank you for all your help and the welcome.

 

[RonD]

I would say no off-hand, as far as bolting on fitment

You are referring to the "Y-pipe", it connects the 2 exhaust manifolds to a single pipe that connects to the Cat usually

But there are different types even in the same year for the same engine

Best bet is to look at yours and then Google: 1997 Ford Ranger 4.0l Y-Pipe

You will often find what years a Y-pipe will fit, once you get past 20 years old this types of parts are harder to find

Some can have 2 smaller Cats, 1 in each down pipe, others just the two down pipes
Either will have 2 O2 sensor bungs, one on each pipe, need those for sure
And either will have a bigger Cat, or 2, after the Y-pipe

This has to do with where this Ranger was first sold and the Emissions requirements in that location, that year

 

[Theroux1113]

I would say no off-hand, as far as bolting on fitment

You are referring to the "Y-pipe", it connects the 2 exhaust manifolds to a single pipe that connects to the Cat usually

But there are different types even in the same year for the same engine

Best bet is to look at yours and then Google: 1997 Ford Ranger 4.0l Y-Pipe

You will often find what years a Y-pipe will fit, once you get past 20 years old this types of parts are harder to find

Some can have 2 smaller Cats, 1 in each down pipe, others just the two down pipes
Either will have 2 O2 sensor bungs, one on each pipe, need those for sure
And either will have a bigger Cat, or 2, after the Y-pipe

This has to do with where this Ranger was first sold and the Emissions requirements in that location, that year

I don’t need the y pipe itself, I need everything after it. Does that change anything? I did notice the cat thing when I went to go look at a parts truck. The one I saw may have 2 cats but I’m not sure.

 

[RonD]

Yes, that matters

There is "Cat back" exhausts, this is the pipe that bolts to the rear Cat, if there are 2, and has the muffler and then the bent pipe that goes up and over the rear axle and the out the side or rear(tailpipe)

The 2005 model should be do-able for that, you will need to look at the bolt pattern on the rear Cat and distance from where it bolts on to the rear axle

One Cat setup is usually shorter than 2 Cats, but if pattern matches up you could use the 2 Cat setup in yours

Regular Cab or extended cab are different lengths as well