• Welcome Visitor! Please take a few seconds and Register for our forum. Even if you don't want to post, you can still 'Like' and react to posts.

2.3L ('83-'97) Running rich, dumping fuel into engine.


Shotrod69

Active Member
U.S. Military - Veteran
Joined
Nov 4, 2023
Messages
30
City
Florida
Vehicle Year
1993
Transmission
Manual
93 ranger with the 2.3.
new fpr, new injectors, new plugs/wires/rear coil

my ranger is running extremely rich, it’ll run for about 15 seconds then die.
I put old plugs back in on exhaust side.
the coolant temp sensor was unplugged and I also jumped it with a paper clip. Didn’t make a difference. With in a few minutes of messing around with it and starting it there will be about 1-1.5” of fuel on the dipstick.
compression is 170~ on all cylinders. Maf plugged or unplugged doesn’t make a difference. Don’t have a good way to test fuel pressure, but it shouldn’t be an issue at the moment right?

any suggestions or help is greatly appreciated.
 
Disconnect both coil pack's 3 wire connector, no spark
Pull out the 4 spark plugs on drivers side
Crank engine over and see which one is expelling the gasoline

If its all 4 then PCM(computer) is the issue

The 4 injectors all get 12volts on 1 wire(the red one) with key on
PCM grounds an injector to open it

Pre-1995 PCMs run Batch Fire fuel Injection most of the time
In a 4cyl this means 2 injector's SHARE 1 ground wire from the PCM, on the 2.3l 1/4 and 2/3 share

So there are 2 ground wires from the PCM to the injectors
If either was shorted to ground then 2 injectors would open with key on, full time

If a PCM "driver"(opens injectors) was bad then 2 injectors would open too long, flooding engine
If PCM was bad then all 4 open too long
But even if its just one "driver" you still have to replace PCM

You can test injector wires, key off, remove connector from injector
The NOT RED wire is the ground, lol
Test it with ohm meter to engine metal, should be no connection, or HIGH ohms, or test light to battery positive, if it lights up that wire is grounded, so shorted wire or shorted PCM

The electric fuel pump can generate 80+ PSI
1993 runs with 30-40psi
So it the new FPR wasn't opening then HIGH fuel pressure could be the issue

There is the RETURN fuel line on the FPR
Remove it
Put a container under FPR to catch any fuel, or a towel or a ???
Cycle key on, fuel pump only runs for 2 seconds, which adds 10psi
Fuel system should hold pressure at 20psi for months and months

Key off and on again, and repeat
There should be fuel coming out of FPR
FPR is set for 43psi max pressure
After the 4th or 5th key off and on if there is no fuel coming out then new FPR is bad

If fuel is coming out then new FPR is OK, pressure is not the issue
 
I did the passenger side plugs, didn’t notice gas coming out. I’ll try again tomorrow when there’s more light. When I pulled the plugs out all 4 were wet. 1/4 were blackened, 2/3 were soaked and were dark.

injector power wire has 12.2V with lead on batt pos(multimeter). ground has 65.5 ohms(ac compressor bolt for ground). 1, 2, and 4 have that with key off. Couldn’t get injector 3 unplugged.

The fpr is the ‘94 2 bolt style. So nothing to disconnect. The new one doesn’t leak, doesn’t smell and can’t blow/suck air through.
 
Disconnect both coil pack's 3 wire connector, no spark
Pull out the 4 spark plugs on drivers side
Crank engine over and see which one is expelling the gasoline

If its all 4 then PCM(computer) is the issue

The 4 injectors all get 12volts on 1 wire(the red one) with key on
PCM grounds an injector to open it

Pre-1995 PCMs run Batch Fire fuel Injection most of the time
In a 4cyl this means 2 injector's SHARE 1 ground wire from the PCM, on the 2.3l 1/4 and 2/3 share

So there are 2 ground wires from the PCM to the injectors
If either was shorted to ground then 2 injectors would open with key on, full time

If a PCM "driver"(opens injectors) was bad then 2 injectors would open too long, flooding engine
If PCM was bad then all 4 open too long
But even if its just one "driver" you still have to replace PCM

You can test injector wires, key off, remove connector from injector
The NOT RED wire is the ground, lol
Test it with ohm meter to engine metal, should be no connection, or HIGH ohms, or test light to battery positive, if it lights up that wire is grounded, so shorted wire or shorted PCM

The electric fuel pump can generate 80+ PSI
1993 runs with 30-40psi
So it the new FPR wasn't opening then HIGH fuel pressure could be the issue

There is the RETURN fuel line on the FPR
Remove it
Put a container under FPR to catch any fuel, or a towel or a ???
Cycle key on, fuel pump only runs for 2 seconds, which adds 10psi
Fuel system should hold pressure at 20psi for months and months

Key off and on again, and repeat
There should be fuel coming out of FPR
FPR is set for 43psi max pressure
After the 4th or 5th key off and on if there is no fuel coming out then new FPR is bad

If fuel is coming out then new FPR is OK, pressure is not the issue

I realize this is an old thread, but I am having a similar issue. I intermittently have voltage on both red and tan wires on every injector, sometimes voltage on just a couple, and sometimes no voltage on any tan wires. Red wires always have battery voltage. My 1990 single cab is really hard starting and has no power past idle if it does. Plugs get fouled and a 7ish mile oil change (fresh oil) is blacker than all get out.
 
Last edited:
I realize this is an old thread, but I am having a similar issue. I intermittently have voltage on both red and tan wires on every injector, sometimes voltage on just a couple, and sometimes no voltage on any tan wires. Red wires always have battery voltage. My 1990 single cab is really hard starting and has no power past idle if it does. Plugs get fouled and a 7ish mile oil change (fresh oil) is blacker than all get out.
Mine ended up being the ecu. Just do what I did and go to the scrapyard and get an ecu. I got mine for $30 and it fixed it.
 

Sponsored Ad


Sponsored Ad

TRS Events

Member & Vendor Upgrades

For a small yearly donation, you can support this forum and receive a 'Supporting Member' banner, or become a 'Supporting Vendor' and promote your products here. Click the banner to find out how.

Recently Featured

Want to see your truck here? Share your photos and details in the forum.

Ranger Adventure Video

TRS Merchandise

Follow TRS On Instagram

TRS Sponsors


Sponsored Ad


Sponsored Ad


Amazon Deals

Sponsored Ad

Back
Top