'86 MJ 2.5L ECM....good?

[SoCalManche]

Just now, Ωhm said:

Connect TL between (A) & (C).

Oh, so clip to jumper and probe the other.

[Ωhm]

You need jumper at FP relay for voltage supply to pump. TL connected between (A) and (C).

[SoCalManche]

1 minute ago, Ωhm said:

You need jumper at FP relay for voltage supply to pump. TL connected between (A) and (C).

Okay okay, I'm sorry but I got lost. Let's refresh.

 

So you want jumper in FP relay; okay, gotcha.

I thought we were testing FP harness on FP side while disconnect, so my bad. You want to test engine side FP harness, yes? Connected or disconnect? I still need a wire to plug into the connecter to clip on to for the TL though.

[Ωhm]

2 minutes ago, SoCalManche said:

You want to test engine side FP harness, yes?

Yes

2 minutes ago, SoCalManche said:

Connected or disconnect?

Disconnect

 

If there're female terminal, yes one end of the TL (probe side) will work, but you may need something like a ice pick for the clip side. Be careful, you don't want them to touch.

[SoCalManche]

1 minute ago, Ωhm said:

Yes

Disconnect

 

If there're female terminal, yes one end of the TL (probe side) will work, but you may need something like a ice pick for the clip side. Be careful, you don't want them to touch.

Yeah, just did it.

 

(A) + (C) = BL.

 

(I haven't had this much fun in math for quite some time!)

[eaglescout526]

Now solve for (X). Lol. 

[SoCalManche]

Just now, eaglescout526 said:

Now solve for (X). Lol. 

(X) keeps eluding us.    

[Ωhm]

We still need to divide (X) out somehow.

[eaglescout526]

But were pretty damn close. 

 

I'm idle by watching the results

 

Comanche Math kids!

[SoCalManche]

2 minutes ago, Ωhm said:

We still need to divide (X) out somehow.

 

1 minute ago, eaglescout526 said:

But were pretty damn close. 

 

I'm idle by watching the results

 

Comanche Math kids!

 

 

Am I delusional or does it seem like (X) is the injector? It doesn't account for the voltage drop at FP harness, but as for the fuel delivery itself, it may be clogged?

[SoCalManche]

2 minutes ago, eaglescout526 said:

But were pretty damn close. 

 

I'm idle by watching the results

 

Comanche Math kids!

Also, should I clean the C100 connector per how Cruiser says to clean the C101?

[Ωhm]

Purpose for testlight request, was it taxes the circuits better then a VM or ΩM would. Both VM & ΩM are high impedance instruments (low current flow). TL allows way more current to flow (ex: BL).

I think all tested circuits are good and not part of the problem. Back to solve for X.
 

[eaglescout526]

(X) could very well end up being an injector problem. 

I would get it as clean as you can get it and make sure the contacts don't have any gunk on them before putting the two halves together.

[SoCalManche]

2 minutes ago, eaglescout526 said:

I would get it as clean as you can get it and make sure the contacts don't have any gunk on them before putting the two halves together.

I better get to scraping.

[SoCalManche]

Found a couple of those pins with a bunch of tar on them. Damn, what the heck was the point of the tar?

[Ωhm]

Soft, smooth grease + 30 years = Tar

[eaglescout526]

Whats bad is it is everywhere. Ive probably cleaned my C101 about 10 times and when my truck has some bizarre issue, I clean the C101 with electrical contact cleaner and that stuff still comes out.

[SoCalManche]

57 minutes ago, eaglescout526 said:

Whats bad is it is everywhere. Ive probably cleaned my C101 about 10 times and when my truck has some bizarre issue, I clean the C101 with electrical contact cleaner and that stuff still comes out.

Is it fine to scrape it off the bottom too, even if it isn't contacting the connectors?

[eaglescout526]

Yup, completely fine.

[SoCalManche]

1 hour ago, eaglescout526 said:

Yup, completely fine.

I've cleaned the connector pretty decently. Before I put it back together, were you about to figure which prong was the FP connection?

[eaglescout526]

Nope, nothin tells me which prong it is. All it says it is on orange wire.

[Ωhm]

Looking at the 86 schematic photo and zooming in, could it be C100_C4.

[eaglescout526]

Good eye Ωhm. I even have the pic up on my second screen and the _C4 is right there in my face.

 

Here this will help:

[SoCalManche]

4 minutes ago, eaglescout526 said:

Good eye Ωhm. I even have the pic up on my second screen and the _C4 is right there in my face.

 

Here this will help:

Why does mine seem different? Missing prongs and seems to be more of a mirror image.

[eaglescout526]

Hmmmmm, well what the pic is from the book is probably what you would see if you tore out the fuse box and were looking at that head on. So my guess is is that some of the prongs on the engine side are probably shared by two smaller clips on the otherside, say if it was a power or ground wire. But that's the only pic the 86 electrical manual gives of C100