1987 Ranger 2.3l Idle issues.

[ljones]

I just put a new set of injectors on the ranger. It doesn't run as rough now but it still hunts at idle sometimes. After the new injectors my MPG went from 15-16 to 14. So far the IAC,MAP, Air inlet temp, Coolant temp, and o2 sensor have all been replaced. Any ideas on what would cause the bad MPG? Could the ECU be going bad?

 

[scotts90ranger]

Where are you located? I know if I was close to you I would lend a hand... that's the mileage my 2.3L turbo gets, yours should get better... it's gotta not be getting in closed loop somehow, throwing parts at it isn't the answer you need to pull codes and do other diagnostics... I'll think about it

 

[ljones]

Where are you located? I know if I was close to you I would lend a hand... that's the mileage my 2.3L turbo gets, yours should get better... it's gotta not be getting in closed loop somehow, throwing parts at it isn't the answer you need to pull codes and do other diagnostics... I'll think about it

Western Kentucky. A long way from Oregon

 

[ljones]

This is the third engine in this ranger. I rebuilt it and all the gasketts and vacume hoses are new. I still was getting 15 MPG when the first motor blew up.

 

[ljones]

I'm on my third tank getting 14 MPG. It has random days when it idles perfectly fine.

 

[tomw]

There are two temp sensors, one for the gauge on the side of the block, and another for the computer. I don't know the second sensor location for 1987 models.
The 'works like a two stroke power band' is what I had when my ignition timing was off. I tried to set it after changing the timing belt w/o removing the jumper plug. The manual stated the timing would be 'static time' for about 2 minutes after startup, so I used that two minute interval to set the timing. Wrong. RONG wrong. It drove gutless until I got to over 2000-2500 rpms when it then kicked in. I had no idea what I had done...
Finally set the timing to 10BTDC with the jumper plug out and it made all the difference. That is the same plug the squirrels ate on my Vulcan ... No warning light or anything, just poorer mileage and gutless operation until I discovered the 'chew'. They also ate the temp gauge sending unit wire... Yum. Wonder what THEY'd taste like after eating plastic ... not likely 'chicken'...
tom

 

[ljones]

The ECU engine temp sensor is on the intake manifold. It has been replaced. The 2-stroke power band stuff stopped after the set of new injectors. The timing was set at 10 degrees BTDC with the SPOUT connector unplugged.

 

[ljones]

I found the correct tester hookup last night. It was hidden down under the HVAC blower motor. My truck has a CEL in the dash but it isn't lit up nor does it light up when you turn the key on. Could the bulb be bad?

 

[scotts90ranger]

most likely after 27 years... you don't need the check engine light to work if you use some type of 12V bulb across where it shows to connect the analog volt meter

 

[tomw]

It is possible your truck did not come with a bulb. They were not a requirement for some time after emissions systems were installed on every vehicle. I know I don't have one as I took the panel out and looked. It also doesn't have the 'upshift now' economy nudge light as shown in the owners manual. Never did.
tom

 

[ljones]

I got my code reader today. It gave the codes 14, 84, 67. The book shows 14 as ignition profile pickup (pip) circuit failure. It shows 84 as EGR vacuum regulator/vent fault. It shows 67 as air conditioning compressor clutch fault. Any ideas on how to fix these or which one is messing with the idle/MPG?

 

[ljones]

In the engine running test I got the codes 42, and 34. The book shows 34 as EVP voltage above closed limit. It shows 42 as HGEO sensor voltage high/ system rich.

 

[tomw]

Code 14 is the one that I'd tackle first. The TFI module has a signal it sends to the computer called PIP (profile I(nductor?) Pickup) which notes that the distributor rotor is turning. There is a plug that is removed to disable PIP when you want to set the initial timing manually by distributor position. It is located hanging out of the harness of wires from the drivers side inner fender to the intake manifold area of the engine. It has a rectangular (mine anyway) plug with a jumper wire that can be removed from a socket to disable PIP. A squirrel (must be...) ate the jumper on my car, and that set timing to whatever position the dist was set at.
If you are missing PIP, it is the jumper fallen out or the TFI is not working, or the wires are bad. If it is intermittent, loose jumper, loose TFI connections, or pickup problems, you may have your timing wander all over the place.
The EGR vent fault might be a bad solenoid. I have two. One supplies vacuum to the EGR diaphragm, the other locks the vacuum in or dumps it to atmosphere. If the vent didn't vent, you could be getting EGR fed to the engine even at idle. A check to see if it is affecting how the engine runs is to disconnect the vacuum line to the diaphragm and plug with a golf tee. See if it idles and runs better. If so, check the solenoids, wires and vacuum lines.
tom

 

[ljones]

Code 67 went away. I think it was becaus the a/c was on during the test. My SPOUT plug is in tact and in its place. I also tested the timing advance and it works fine.

 

[ljones]

The egr solinoid is shot. It doesn't pull vacuum on the egr any any RPM. It just makes a loud clicking sound. The part is impossible to find also. None of the parts stores have any. They're all no longer available. Any ideas?