New to forum and think I have read most posts referencing a Code 18 and SPOUT issues. My trouble shooting results are slightly different from the other posts I have read so sharing to get some insight for next step in solving my problem.
I have a 93 LX 5.0 5spd convertible. Two weeks ago took it out as usual except it took three attempts to start vs the usual start on first try. 1.5 miles down the road, pull it out of gear approaching a stop and the idle drops, stumbles and engine dies. Would not restart within an hour, towed it home and checked for codes. Code 18 is only code that came up. I started scouring forums and internet for some Code 18 wisdom. Found a lot of information here, but not a perfect fit or fix for my situation yet.
I have owned the car for only four months so I have inherited a lot of unknown history. It is 60k miles, relatively stock with exception of last owner adding a Vortech and not much else. The owner prior to him installed a 5spd in place of automatic and a 3.55 rear in place of 2.80 all done with factory OEM parts, no aftermarket or performance pieces to be found. The computer is an F3ZF-FA so appears to be correct for current set up
The fuel pump primes with key on and has pressure, but I have not measured it with gauge yet. My coil and distributor/TFI appeared to be factory original Motorcraft. I planned to replace them soon for peace of mind so thought I would start there. First I attempted to start the car without any changes. It fired up with SPOUT in and ran rough, eventually stalled. I swapped out the coil and again it started up and ran rough, eventually stalled. I then swapped the distributor for a new unit (not remanufactured) with new TFI and again it started (SPOUT out to set timing) 10BTDC, it ran rough like the original distributor, no change. I put the SPOUT in and the engine stalled almost immediately. I checked the timing when I first got the car and it was at 10BTDC and the SPOUT did advance the timing 4 degrees when installed.
I then began following the Code 18 troubleshooting logic from this forum and will add my results and questions in the copy paste of the procedure below for reference.
Code 18 - SPOUT out or wiring fault - look for short to ground in SPOUT wiring going back to the computer. Possible bad TFI or defective 22 K resistor in the IDM wiring
Use a timing light to check the timing: remove the SPOUT and observe that the timing retards at least 4 degrees. Put the SPOUT back in place and observe that the spark advances at least 4 degrees. Timing at 10BTDC with or without the SPOUT, no timing change removing spout. I noticed that when handling the spout pigtail that the engine rpm did vary noticeably. I found the SPOUT was loose and not continuously connected. I disassembled the spout plug, bent the tangs of the female connectors to better engage the SPOUT blades. SPOUT now plugs firmly in place with continuous contact. Still no SPOUT effect on timing. Engine struggled to run with SPOUT in and does not start with SPOUT in. After fixing SPOUT plug, I still noticed changes in engine running when handling the TFI harness near the plug, not as bad as loose SPOUT but noticeable. I soldered in a new TFI connector and this fixed the variations upon handling the harness. Checked to see if code 18 went away - still there. Ran car, would not start with SPOUT in, no change.
This code can disable spark advance and reduce power and fuel economy.
Remove the passenger side kick panel and disconnect the computer connector.
There is a 10 MM bolt that holds it in place.
Disconnect the TFI module connector from the TFI and the measure the resistance between the yellow/lt green wire and ground.
You should see greater than 100 K (100000) ohms. I have infinite resistance or open circuit, so greater than 100K ohms
Check the resistance from Pin 4 on the computer connector (dark green/yellow) and the dark green/yellow wire on the TFI connector. You should see 20-24 K Ohms (20,000-24,0000 ohms).
21.8K ohms
PIP Sensor functionality, testing
Some simple checks to do before replacing the PIP sensor or distributor:
You will need a Multimeter or DVM with good batteries: test or replace them before you get started.. You may also need some extra 16-18 gauge wire to extend the length of the meter’s test leads.
Visual check first: look for chaffed or damaged wiring and loose connector pins in the TFI harness connector.
Check the IDM wiring – dark green/yellow wire from the TFI module to pin 4 on the computer. There is a 22K Ohm resistor in the wiring between the TFI and the computer. Use an ohmmeter to measure the wire resistance from the TFI to the computer. You should see 22,000 ohms +/- 10%.
21.8K ohms
Check the PIP wiring - dark blue from the TFI module to pin 56 on the computer. Use an ohmmeter to measure the wire resistance from the TFI to the computer. You should see 0.2-1.5 ohms.
0.2 ohms
Check the SPOUT wiring – yellow/lt green from the TFI module to pin 36 on the computer. Use an ohmmeter to measure the wire resistance from the TFI to the computer. You should see 0.2-1.5 ohms.
0.2 ohms
Check the black/orange wire from the TFI module to pin 16 on the computer. Use an ohmmeter to measure the wire resistance from the TFI to the computer. You should see 0.2-1.5 ohms.
0.2 ohms
Check the red/green wire; it should have a steady 12-13 volts with the ignition switch on and the engine not running.
Steady 12.0 V
Check the red/blue wire; it should have a steady 12-13 volts with the ignition switch in Start and the engine not running. Watch out for the fan blades when you do this test, since the engine will be cranking.
10.0 volts while cranking. Definitely not 12-13 volts. What is the corrective action for this condition?
Thanks,
I have a 93 LX 5.0 5spd convertible. Two weeks ago took it out as usual except it took three attempts to start vs the usual start on first try. 1.5 miles down the road, pull it out of gear approaching a stop and the idle drops, stumbles and engine dies. Would not restart within an hour, towed it home and checked for codes. Code 18 is only code that came up. I started scouring forums and internet for some Code 18 wisdom. Found a lot of information here, but not a perfect fit or fix for my situation yet.
I have owned the car for only four months so I have inherited a lot of unknown history. It is 60k miles, relatively stock with exception of last owner adding a Vortech and not much else. The owner prior to him installed a 5spd in place of automatic and a 3.55 rear in place of 2.80 all done with factory OEM parts, no aftermarket or performance pieces to be found. The computer is an F3ZF-FA so appears to be correct for current set up
The fuel pump primes with key on and has pressure, but I have not measured it with gauge yet. My coil and distributor/TFI appeared to be factory original Motorcraft. I planned to replace them soon for peace of mind so thought I would start there. First I attempted to start the car without any changes. It fired up with SPOUT in and ran rough, eventually stalled. I swapped out the coil and again it started up and ran rough, eventually stalled. I then swapped the distributor for a new unit (not remanufactured) with new TFI and again it started (SPOUT out to set timing) 10BTDC, it ran rough like the original distributor, no change. I put the SPOUT in and the engine stalled almost immediately. I checked the timing when I first got the car and it was at 10BTDC and the SPOUT did advance the timing 4 degrees when installed.
I then began following the Code 18 troubleshooting logic from this forum and will add my results and questions in the copy paste of the procedure below for reference.
Code 18 - SPOUT out or wiring fault - look for short to ground in SPOUT wiring going back to the computer. Possible bad TFI or defective 22 K resistor in the IDM wiring
Use a timing light to check the timing: remove the SPOUT and observe that the timing retards at least 4 degrees. Put the SPOUT back in place and observe that the spark advances at least 4 degrees. Timing at 10BTDC with or without the SPOUT, no timing change removing spout. I noticed that when handling the spout pigtail that the engine rpm did vary noticeably. I found the SPOUT was loose and not continuously connected. I disassembled the spout plug, bent the tangs of the female connectors to better engage the SPOUT blades. SPOUT now plugs firmly in place with continuous contact. Still no SPOUT effect on timing. Engine struggled to run with SPOUT in and does not start with SPOUT in. After fixing SPOUT plug, I still noticed changes in engine running when handling the TFI harness near the plug, not as bad as loose SPOUT but noticeable. I soldered in a new TFI connector and this fixed the variations upon handling the harness. Checked to see if code 18 went away - still there. Ran car, would not start with SPOUT in, no change.
This code can disable spark advance and reduce power and fuel economy.
Remove the passenger side kick panel and disconnect the computer connector.
There is a 10 MM bolt that holds it in place.
Disconnect the TFI module connector from the TFI and the measure the resistance between the yellow/lt green wire and ground.
You should see greater than 100 K (100000) ohms. I have infinite resistance or open circuit, so greater than 100K ohms
Check the resistance from Pin 4 on the computer connector (dark green/yellow) and the dark green/yellow wire on the TFI connector. You should see 20-24 K Ohms (20,000-24,0000 ohms).
21.8K ohms
PIP Sensor functionality, testing
Some simple checks to do before replacing the PIP sensor or distributor:
You will need a Multimeter or DVM with good batteries: test or replace them before you get started.. You may also need some extra 16-18 gauge wire to extend the length of the meter’s test leads.
Visual check first: look for chaffed or damaged wiring and loose connector pins in the TFI harness connector.
Check the IDM wiring – dark green/yellow wire from the TFI module to pin 4 on the computer. There is a 22K Ohm resistor in the wiring between the TFI and the computer. Use an ohmmeter to measure the wire resistance from the TFI to the computer. You should see 22,000 ohms +/- 10%.
21.8K ohms
Check the PIP wiring - dark blue from the TFI module to pin 56 on the computer. Use an ohmmeter to measure the wire resistance from the TFI to the computer. You should see 0.2-1.5 ohms.
0.2 ohms
Check the SPOUT wiring – yellow/lt green from the TFI module to pin 36 on the computer. Use an ohmmeter to measure the wire resistance from the TFI to the computer. You should see 0.2-1.5 ohms.
0.2 ohms
Check the black/orange wire from the TFI module to pin 16 on the computer. Use an ohmmeter to measure the wire resistance from the TFI to the computer. You should see 0.2-1.5 ohms.
0.2 ohms
Check the red/green wire; it should have a steady 12-13 volts with the ignition switch on and the engine not running.
Steady 12.0 V
Check the red/blue wire; it should have a steady 12-13 volts with the ignition switch in Start and the engine not running. Watch out for the fan blades when you do this test, since the engine will be cranking.
10.0 volts while cranking. Definitely not 12-13 volts. What is the corrective action for this condition?
Thanks,