Help!

[Tfree]

I have a 200 Ford Ranger. The check engine light came on. So I bought a code reader. Which c
Showed that "1 bank is running rich"
It's a FOUR CYLINDER (with 8 spark plugs) so how can ONE BANK be running rich!! and how can I correct the problem?!? The MPG seems wasn't good compared to my other Ranger, which was a northern truck that I finally had to scrap because of the rust. Even though it couldn't of run any better!
Anyway. How can I correct this problem?!? Because I just signed into this site and have no idea where to find responses. PLEASE contact me directly at, one word of course. t Reeves 672 at gm.
THANK YOU!!!!

 

[RonD]

Welcome to TRS

V6 or V8 engines have Bank 1(passenger side) and Bank 2(drivers side)

4cyl just has Bank 1

Code readers are setup to do either type of engine

Was the exact code P0172 System too Rich (Bank 1)?
There is more than one "rich code"

In a 1998-2001 2.5l engine this means the computer needed to add LESS fuel than it calculated to balance O2 sensor voltage

You mention a drop in MPG?
So could be one of the fuel injectors is leaking or sticking open

Try this test
Key on engine OFF
Press gas pedal down to the floor and HOLD IT DOWN all the way
Try to start engine
It should NOT start, it should NOT fire at all, it should just spin
If it starts/fires then its more than likely a fuel injector is leaking fuel

Other things
When were O2 sensors last changed?
These sensors use a chemical to detect oxygen in the exhaust, and they run out of that chemical after 100k miles or 12 years, this will cause rich running
O2s are the ONLY sensors that "wear out" and need to be changed

Fuel pressure
It should be 55-65psi at the engine, there is a test port
If fuel pressure regulator in the gas tank fails then you could be running 90psi pressure and TOO MUCH fuel is flowing out of injectors when computer opens them, so rich codes

MAF sensor calculates air WEIGHT as it comes in, if its misreading the weight then that could cause rich codes
Very easy to "clean" the MAF sensor

 

[dvdswan]

Welcome to the site.

 

[Tfree]

I can't thank you enough for passing on your expertise!!

I did try to start the engine as you suggested and it just spun! 1 potential problem eliminated!

I plugged in my code reader (only used once). It's weird because the screen on its app flashed 'connect' (device) but when I clicked on connect, my phone went to Bluetooth and it showed that the code reader WAS CONNECTED. So I went back, clicked on connect. Same thing!

So I turned Bluetooth off for 5 minutes but within seconds of turning Bluetooth back on, it connected to the device BUT when I opened the app for the device, it STILL FLASHED CONNECT!!

I tried everything for an hour and a half and decided that I'd better walk away before I walked 50 ft to the lake to give the reader the float test!

The 'rule' for the float test is something that I learned in the Navy.

You throw whatever it is in the ocean or lake.

If it sinks, it's junk anyway!
If it floats. Get it out quickly. Because it's fixable!

I wrote the support team but because they're in Japan. Who knows when I'll hear from them! Grrrrrrrrrrrrrr!!

When I get the code reader working again I'll be able to tell you the problem code.

Again. Thank you very much for sharing your expertise! I truly do appreciate you!!

 

[Tfree]

Today my code reader finally connected to my truck! It brought up 3 codes.

PO 442 evap system small leak detected.

PO 445 evap sys large leak detected.

PO 173 sys too rich bank 1

I removed the MAF sensor. Which was close to the air cleaner and just before the rubber hose.Thinking that it was dirty but when I removed it, there was only small 2 electronic pieces, no idea what they are. Soldered to an 'arm' they were not connected to each other, at least in any way that I could see. Neither shower any signs of overheating or discoloring.
So my next move is.......???
Many thanks!!!
Tom

 

[RonD]

The EVAP codes won't effect engine operation at all, just FYI
They mean the gas tank is no longer sealed from outside air when gas cap is on
Most common issue is the gas cap was left off in the past, lol, and the codes were never cleared
After that its the Filler/vent tubes have an air leak, its the parts that connect gas cap opening to the top of the gas tank, rubber cracks and leaks air


The MAF sensor is as you described, that's all it is, you spray it with NON-RESIDUE electronics cleaner or MAF Cleaner(same thing but costs more) to clean it


P0173 Rich on Bank 1
This means the computer's calculated OPEN TIME for the fuel injectors was too long

The computer KNOWS its running a 2.5 LITER engine, so it KNOWS exactly how many liters of air are coming in at, say 1,000rpms, its just math and that's what computers are good at, they "compute"

Side track
Gasoline engines need an air/fuel ratio of 14.7/1, this is a WEIGHT RATIO
14.7 pounds of air to one pound of gasoline
14.7grams of air to 1 gram of gasoline

Gasoline pretty much weighs the same when its -20deg or 120deg
But AIR on the other hand changes its weight ALOT
"Hot air rises", why, because it LIGHTER than cooler air
Air is LIGHTER at 5,000ft elevation(Denver) than at sea level

Back to the Rich thing
The MAF sensor WEIGHS the air as it passes by
There is also an "air temp" sensor(IAT or ACT)
Computer uses both to determine how much each liter of air weighs on the fly
Then it can calculate how much gasoline to add at that moment to that weight of air
Lets say it opens each injector 100ms(millieseconds), this calculation is called STFT 0

Computer then looks at the O2 sensor to see if it was a lean burn(too much oxygen left) or rich burn(not enough oxygen left)
If lean then computer opens injectors 102ms, 2% longer to add more gasoline
If Rich then computer open injectors 98ms, 2% less to reduce the amount of gasoline
This all takes less than 1 second
Lean and Rich codes don't mean the engine is actually running lean or rich, it means the calculations are lean or rich

To get a Lean or Rich code the computers calculation needs to be off by at least -/+ 15%, STFT -15 to STFT +15
The code is to let the driver know that there is a problem with the on the fly calculations

Lean codes are way more common because vacuum leaks are way more common, and fuel pump issues lower fuel pressure so less fuel flows out of injectors

Rich codes are tougher, I would clean the MAF first
If you can get/rent a fuel pressure test gauge that would be next step
2000 should be running 55-65psi fuel pressure, if the regulator(in the gas tank) has failed it could be 90psi and that would cause rich code

Also if you can get your Reader working, watch Live Data while driving to see what STFT is doing, while cruising and accelerating

 

[Tfree]

Can't tell you how much I appreciate your response but a lot of it is Greek to me! I'm just an old fart that is completely lost with new technology!!
I really miss the old engines! AND things like the cable operated cabin temperature control, cable transmission shifting control, tied to the carb and everything else with the old cars and trucks!
Now it not only takes a computer to read the vehicles computer but also a REALLY SMART person to understand it all and I say that with all sincerity!!!
The old engineers believed in and used the KISS method. Which is,
Keep It Simple Stupid!!
Thanks again!!

 

[RonD]

The new stuff is WAY simpler than the old stuff

Old guys, like us, just knew the older stuff better because we had to WORK ON IT ALL THE TIME, lol, there was no "set and forget"
You would have to spend at least one Saturday a month to do adjustments on yours and other vehicles

The biggest problem with the newer vehicles is that they are way more reliable, lol
When they do have a problem you have to re-learn it all again, because you forget what did what

Older stuff was learned, and remember, from shear repetition

Give me the new stuff any day

Its the same 3 things for a gasoline engine
Compression
Spark
Fuel

Compression hasn't change, rings and valves, piston goes up and down, if its timed correctly then its above 140psi

Spark is way easier now, no distributors or points
You basically just have spark plugs, gaps and wires to check or change

Fuel can be the stumbling block but the computers rarely break, so its usually a mechanical issue, like fuel pump or filter
Sensors rarely fail but are often replaced, lol
O2 is the only sensor that "wears out", it uses a chemical to detect Oxygen in the exhaust and simply runs out of that chemical, they need to be changed every 100k miles or 12 years, which ever comes first

MAF sensor can get dirty, easy to clean, other sensors just need to be unplugged and plug back in, their connectors get dirty and they run under 5volts so a little corrosion changes voltage alot, unplugging and plugging back in cleans the contacts inside the connector
This is why a New sensor can fix a problem, because you have to unplug it to install the new one, so...................you cleaned the connection