TurboFource HalfDork
6/3/23 6:02 p.m.

Out of town trying to help my son get his 1986 SVO Mustang running.

It is throwing code 18. He has put in a remanufactured distributor, new TFI module, and coil.

We are getting continuity all the way from spout to computer connector. Online We found mention of a resistor in the IDM wire 6" from connector but can't find the resistor to measure?


Any suggestions/insight/help would be appreciated, this is above my pay grade!!

Blunder Reader
6/3/23 6:58 p.m.

This probably isn't gonna be too helpful but I remember back when I had a 91 5.0 my car would run lean and the internet forums pointed me to a resistor in the wiring harness. It was part of the main harness located along the firewall. I had to remove the wire loom and any tape obviously to find it.  Apologies if this isn't any bit helpful. 


tester (Forum Supporter)
tester (Forum Supporter) Reader
6/3/23 7:04 p.m.

18 is spout connection grounded. The spout connection is a little connector that allows you to lock out computer timing control for setting base timing. 

TurboFource HalfDork
6/5/23 7:24 a.m.

While the timing belt has only about 8K on it it was over 20 years old (was loose) and it jumped a couple teeth. Changed that and it will now run poorly. It throws no key on engine off codes now and a couple codes running because we didn't run at full throttle because it is running bad, no knock sensed, etc.

The ignition timing seems to be very retarded (I can't even see the timing mark with the light) and we had to advance it quite a bit to get it to run. When I put the timing mark at 10 BTDC the rotor is well past the number one post in the cap...any idea why it would be trying to pull the timing so much (would a bad knock sensor do this)?

The TFI/SPOUT connector is in poor shape as the previous owner had the distributor positioned so the wires were bent by the intake at a 90 because of interference with the manifold, we will be changing this.

The car has a PE processor, I have one from a XR4T1 and distributor etc we can swap in to try...


Any insight appreciated!! I would like to get this thing going so my son can go to cars and coffee etc. in the Hampton VA area.

TurboFource HalfDork
6/5/23 7:48 a.m.

We plan to check fuel pressure etc...I didn't have all this with me (I live 3 hours away) since I thought we would swap in a distributor and be happily driving....frown

Ranger50 MegaDork
6/5/23 8:20 a.m.

If your rotor is past #1, you are off teeth on the distributor vs the auxiliary shaft. Retime the distributor to be before #1 tdc. Then really set timing with spout pulled and a timing light. Once base timing is set, reinstall the connector.

TurboFource HalfDork
6/5/23 8:52 a.m.

I started off with it pointing at number one and had to advance the distributor that much to get it to run.

iammclovin804 Reader
6/5/23 9:42 a.m.

Any chance you put the distributor in 180* out?

RossD MegaDork
6/5/23 10:13 a.m.
APEowner GRM+ Memberand UltraDork
6/5/23 11:39 a.m.

If you've got timing issues then you need to go back to basics.

With the engine at TDC #1 firing make sure the timing belt marks lined up correctly.

If the are put the front of the engine together and make sure that the timing mark on the front pulley lines up with the TDC mark on the front cover or wherever you check ignition timing. 

Once you're sure that that's correct back the engine up so that you're at 10 degrees BTDC and install the distributor so that the rotor is pointing at the #1 post.

Adjust the distributor so that the high spot on the reluctor is just past the sensor and make sure the rotor still points at the #1 post on the distributor.

Pull the spout connector and start the engine.  It should start and you shouldn't have to move it much to get the timing where it needs to be.

If you can't get one of those steps to work then you'll need to figure out what's wrong at that point.  Also, remember that new parts doesn't mean good parts. 


TurboFource HalfDork
6/5/23 12:14 p.m.

 I tried the distributor 180 out to be sure that wasn't the problem.


"Also, remember that new parts doesn't mean good parts. "       I worry about this part as I have found it to be true!


Unfortunately it will be 3-4 weeks before I can get back to my son's place. 

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