[T3] Mystery Miss

[Daniel Nohejl]

> For some reason, I was not able to view the second video, but in the 
> first video you're putting a lot of force on the loop of wire going 
> to the pressure sensor. Wiggle the individual wires going into the 
> pressure sensor connector.

Weird…..the link works for me. The beginning of the video shows me fiddling with the MPS connector to see if there was bad contact, but it seemed fine as there were no misses or cut outs. The remainder of the video is us fiddling with the rest of the connectors to no avail until Jessica pulls on the 3/4 injector wires and the motor cuts out. Again, that’s what made me think there must be a harness issue.

> Then work your way out along the harness, to the other connectors. 
> Find the place that just takes a light touch in the right direction 
> to kill the engine.
> 
> One thing to keep in mind is that sometimes you can get a wire that's 
> broken INSIDE the insulation. This can happen anywhere along the 
> wire, but it generally only happens with wire that has suffered a lot 
> of flexing over a lot of time, so I don't think this applies to your 
> "new" FI harness. But it could apply to the 2 wires coming from the 
> FI power relay. To test for this, pull on each wire. If the conductor 
> is broken that will disconnect it.

This is what’s making me think Sean is right and we’re going to have to cut open the heat shrink/sleeving so we can get better and more thorough access to individual wires at multiple points. Is that a bad idea? It’ll be a bitch to re-sheath those wires properly later on. At the same time, Joe used some fancy teflon coated silver stranded wire and I imagine it’d take quite a trauma to break it but it might be worth looking. Unless he had an issue when building the harness and had to make a repair to a wire and it’s now failing?? 

I was also thinking that with the motor off we could hook the DVOM up to each wire at the MPS plug and to each corresponding wire at the ECU plug end and look for continuity. In flexing the wires, we might find a break in continuity in one of them and that’ll tell us which one is bad. Couldn't that work?

We paid a lot of attention to the wires from the power relay and nothing seemed to be amiss (no missing or cutting out), but we can check again. 

> Another possibility is that a wire slipped forward or backwards just 
> before a crimp was made. If forward, the inner crimp will be on 
> insulation and the connection will be accidental and intermittent. If 
> backwards, the bare part of the conductor may not be within the part 
> of the connector that was crimped, and again the connection will be 
> accidental and intermittent. Either way will respond to force in 
> various directions.

I also wonder if there’s something else with connectivity….For example, when first connecting the female ends of our adapters for wires 16 and 24 to the long male connectors, we managed to wedge them between the connector and the plastic rather than slide them onto the connector. I suppose this could also be happening at the MPS….the metal connectors might not be fitting correctly and the pins on the MPS are resting between one metal side of the wire end and the plastic connector. 

If it comes to it, what’s a good source for those small silver female connector ends? I’m not even sure what size they are. 3mm?

Also, Jim, the B brain you repaired has been running perfectly fine for over a week. I can now definitely send you back your B brain if you want it.