No start issue after re-installing WBO2

OK, so these things are probably NOT connected, but that is really all I have done to the car, and now it won't start.

It's the B21FT with MS1V3.0 w/ Extra. LH2.2 dist. Ford "e"coil (Like what you would find in an 80's 2.3T Ford). Has been running that way for 2-3 years now.

Anyway, the car had been running and being tuned with my 14point7 SLC Free B. That took a dump a couple months ago, so to keep the car on the road, I swapped back in the NBO2 and changed that setting in TS.

Car has been running fine, and I think I last drove it about a week ago.

I picked up a 14point7 Spartan WBO2, and get it installed today. Changed/disturbed no wiring on the current set-up, other than to unplug the O2 signal wire.

I changed the setting in TS back to the WBO2 and went to start the car. Cranks but no tach signal in TS nor the tach (which is a factory tach, fed from the coil).

The resistances in the coil windings are inconclusive (1.7 on the primary and 8K on the secondary). So it MAY be the coil. (That type can fail suddenly vs the oil canister type)

Doing another check to see if the dist is working, I put the key in RUN and rotate the dist back and forth by hand, and I *should* hear the injectors at least click when the hall sensor is triggered. Nothing there either.

So, did the coil fail or the Hall effect in the dist just fail, while the car was sitting?

Make sure the hall sensor is getting power. If it is, make sure the hall sensor output moves between 5v and ground when rotated.

gross polluter said:

Make sure the hall sensor is getting power. If it is, make sure the hall sensor output moves between 5v and ground when rotated.

Click to expand...

I'll have to dig back into the connector wiring on that, to see what is what. Went through all that 3 years ago, when I was getting the car together. Had a bad HE at that time (Among other things).

Well, it's not the coil. I had a known good one in hand. Still nothing when I swapped that in.

I'll have to dig into the wiring for the HE tomorrow, when I get a free moment.

If you have no tach signal in TS, the core issue won't be anything on the coil/ignition side as that cannot fire without tach sync in MS.

The issue is between the distributor and MS.

OK, getting back to this.

There is 12V at the dist with the key in RUN. On the signal wire back to the MS, I have a constant ~5V when checking and rotating the dist. It doesn't change. (This is while probing the signal and the ground terminals at the dist connector).

If the output stays at 5v and doesn't drop to 0v when a vane passes through the sensor, you have a bad hall sensor.

gross polluter said:

If the output stays at 5v and doesn't drop to 0v when a vane passes through the sensor, you have a bad hall sensor.

Click to expand...

Sigh.

So it just died while sitting the past week?

That 5V should be checked at the signal and "-" terminals on the dist connector, correct?

Chuck W said:

That 5V should be checked at the signal and "-" terminals on the dist connector, correct?

Click to expand...

it's an open collector output. When the vane passes through the sensor, the output will ground. You can test it a number of ways. If the output remains high and doesn't go to ground, it's not working.

Well, I double-checked it. Stays at ~5V. Nothing happens when it rotates.

The test leads wound up touching (accidentally) when one of the multimeter ends came loose. When that happened, the injectors cycled. So it sounds like the MS works and I have another dead HE sensor.

Correct, by shorting the leads you grounded the input to the MS just as the hall sensor would if it was operating properly.

gross polluter said:

Correct, by shorting the leads you grounded the input to the MS just as the hall sensor would if it was operating properly.

Click to expand...

Thanks for the assistance. Sucks that it failed just sitting in the garage, but I suppose that's better than on the road someplace.

Now to find another dist, or replace a sensor in one of the two dead dists I have.

I have noticed an occasional miss on hot days that was new in the past couple months. Would a failing HE cause that, or do they just GO when they're done?

OK, well either I'm having terrible luck with distributors and HE sensors, or something else is amiss.

Still trying to get this thing sorted out.

I picked up another distributor (used, but unknown if actually working). I plugged the dist connector into it and put the key in ON. Rotating the dist had no results (no injector firing, etc). I unplugged it and bench-tested it like I had done WAAY back when I was dealing with this same issue before. No apparent signal. So I sent that one back.

As a back-up plan, I had been looking into replacement sensors (There are LOADS of HKZ101 equivalents available online), and happened to find one with a proper connector HERE. Most of the sensors just come with a pigtail and no pins, etc. See HERE for documentation

That showed up today and I went about swapping that into my old bad dist from before. The two big hassles with that are getting the gear pin out and the wires on the sensor were too long. Luckily the sensor came with the pins only soldered and not crimped.

Desoldered those and shortened the wires and crimped the pins.

I reassembled that whole lot back into the dist and plugged it into harness on the car. Again, key ON and rotating this "new" dist. Again nada. Bench tested it as well. Zilch.

My bench-test assembly uses an old dist connector. I connect the + and - to the battery and the leads on the multimeter to the - on the battery and the signal from the sensor.


I get no change in the signal voltage. I should be seeing it bounce between 12v and 0v, as I rotate the dist.

So, either I've gotten a bad dist, as well as a defective sensor, or I'm missing something...

I get 12V in the dist connector on the car with the key in ON, so it's getting power. When I jumper the signal and the - pins at the connector, the ECU reacts like it's getting the signal to fire, as it fires the injectors (and actually sparked a bit, because the engine turned over).

Any other ideas aside from just bad luck?

Ok, well it appears that I am just dealing with bad luck.

I went out and checked the dist with the "new" sensor again. Using a hint from an old thread of mine on this from HERE, I get no resistance change between the signal and ground terminals when I rotate the vane through the sensor while bench testing.

At least the sensor was cheap, but it being DOA still does me no good.

To test the sensor when not connected to MS, you need a pullup resistor between the sensor Output signal (green wire on hall module) and +12v. Anything between 1K and 10K ohms is OK for testing. With this, the Output signal should be ~12v when the metal flag is in the sensor gap and ~0v when the gap is opened. Without the pullup, you'll read ~0v at all times. Unfortunately, it looks like the sensor is bad since you're reading ~12v without pullup. Or do you have the pullup already installed in the harness and hidden by shrink wrap?

Just to check: sensor red wire goes to +12v, black to ground, green is sensor output.

bobxyz said:

To test the sensor when not connected to MS, you need a pullup resistor between the sensor Output signal (green wire on hall module) and +12v. Anything between 1K and 10K ohms is OK for testing. With this, the Output signal should be ~12v when the metal flag is in the sensor gap and ~0v when the gap is opened. Without the pullup, you'll read ~0v at all times. Unfortunately, it looks like the sensor is bad since you're reading ~12v without pullup. Or do you have the pullup already installed in the harness and hidden by shrink wrap?

Just to check: sensor red wire goes to +12v, black to ground, green is sensor output.

Click to expand...

I was bench checking it as per this post HERE. Power to it and checking the resistance/continuity between signal and ground. I get no changes.

This set-up was put together in Dec of '13. The original dist died in Jan or Feb of '14. After chasing down that it was indeed the dist, after a few tests, I installed another known good one, and the car had run fine until a couple weeks ago.

The trigger set-up is wiring as per the manual HERE (12V Lo-Hi).

As mentioned previously, when I jumper the signal and - terminals at the harness, the ECU reacts and fires the injectors, etc, so that is my indicator that the harness/ecu are fine, and the dist is bad.

I keep thinking back and checking to see what I might've done by re-installing the WBO2, but nothing is standing out.

I don't know what wire colors Volvo used on your car. On the disti, there should be an embossed "- O +" under the connector. The - pin should go to black wire of new hall sensor, and should go to MS ground. The O pin should go to green wire of new hall sensor, and to MS hall input pin. The + pin should go to red wire of new hall sensor, and to either +12v or +5v (from MS).

If the connector is still separated from the harness, I'd carefully cut off the shrink wrap and make sure nothing is shorting out out of sight.

bobxyz said:

I don't know what wire colors Volvo used on your car. On the disti, there should be an embossed "- O +" under the connector. The - pin should go to black wire of new hall sensor, and should go to MS ground. The O pin should go to green wire of new hall sensor, and to MS hall input pin. The + pin should go to red wire of new hall sensor, and to either +12v or +5v (from MS).

If the connector is still separated from the harness, I'd carefully cut off the shrink wrap and make sure nothing is shorting out out of sight.

Click to expand...

Yeah, the wiring on the car appears to be good. If I short the "O" and "-" pins in the harness, with the key "ON", all the appropriate things happen. I'll investigate my "bench test" connector/harness, but that seems to be OK too. This set-up has been running fine for the past 3 years, and only decided to "die" when I was swapping the WBO2 back in.

The new sensor is wired correctly, even though, on a lot of the replacements I've seen, they've shuffled the order of the wires coming out of the sensor. (R-B-G, instead of R-G-B), but all the documentation still says that the green is the signal.


I just can't seem to get a good dist or HE sensor, evidently.

I'm not sure if checking the resistance of the hall module (when powered) is a good measurement -- I think it may depend on your meter and which way you connect the leads. If you include a pullup resistor, and then measure sensor output voltage, it matches the way MS uses the circuit. You can also check just the sensor (out of the disti) by passing a feeler gauge through the gap.

It's weird that you've had so many disti/hall sensor problems. Is there anything unusual, unique or non-standard about your MS setup?