Crank sensor and harmonic balancer

35th

Registered User
So I just replaced my harmonic balancer with a bhj after my stock balancer broke also replaced the crank sensor but the sensor is somehow lightly touching the fins of the balancer making an audible sound. I did notice that the sensor has oblong holes making it somewhat adjustable but it still touches the fins on the balancer no matter what position I put it in anyone else ever have this problem or no a way to correct it?
 
Last time I did a crank sensor on a 89-93 I used painters tape on the balancer fin/trigger ring. 2 or 3 layers did the trick. Turned the crank manually till the sensor was in the painters tape area, then tightened it down. Seemed like no matter how hard I tried otherwise the magnets in the crank sensor would move it when I was trying to tighten it. Once the sensor was tightened, removed the tape and the few thousands from the tape was enough to make sure everything cleared.

I beleive years ago a match box was suggested but those are pretty much extinct these days.

Good luck.

-Tim
 
Great advice

I certainly appreciate the advice and I like the idea will try to do that the next time I work on it probably late this week and I'll update if that works
 
Inspect your reluctor ring carefully. There is a good chance if you are using your old one that it might be bent slightly.
 
The relucter ring came with the balancer which is new

You say the old balancer broke...how savage was that?

Was the replacement a clean affair? Timing cover undamaged? Pulley went right on, or was it replaced too? Any drilling to get things back together? Did you have to get creative at any point during re-install/assembly? Did it go together right the first time?

Can you put some sort of run-out/dial indicator on the balancer and trigger ring to see if they wobble while the engine is turned over by hand?

Did you eyeball the trigger ring to be sure it wasn't bent/damaged at any point?
 
It was a clean break low rpm no damage to the pully didn't see any damage to ring no problem replacing it was a litt difficult getting the old one off but made sure not to scar the crank and can't see any woble when I turn the engine over using a remote switch to the selinod
 
Yeah I realized after I posted that I did reuse the old one but it didn't appear to be bent at all but somehow probably from incorrect adjustment it messed up the crank sensor so I've got to locate another one I'm getting a no start and constant cel and shift light
 
Ground wire???

So on the crank position sensor where does the ground attach on the bottom end of the harness near the sensor itself I have 2 separate sensors and both of them the ground wire is broken but I can't see what it was attached to to repair it
 
I can't see what it was attached to to repair it

It's not broken. It doesn't connect/attach at the sensor. It's a non-current carrying shielding path to up the pigtail and into the main harness, back to ground at the ECU. Make sure it's covered up at the sensor is all you need to do at that end. It needs to be shielding and bundled with the four colored leads off the sensor. See the EVTM if you have one.

It is a loose lead at the barrel connector on the other end of the pigtail, right side your image, on it's own, but the connector on that end is missing in your photo. There should be a free grey square single wire on the front harness, near the upper tensioner along the accy. bracket for the A/C and DIS mount. Yell if you need pics (or if you need the plastic connector, I have a bucket full), but it's the same type single wire connector at the main harness top/front/pass. side of the supercharger hat, and the noise suppressor connector at the coil.

I'd use the most intact, clean, serviceable sensor & pigtail you've got onhand. The shielding in the pigtail/harness(es) is to reduce EMI, and it's important that it be in place and unmolested, so resist the urge to swing too much weight when doing repairs. As good crank sensors are in short supply, do your best to stay as close as possible to the original construction.

If you have phantom issues traced to the sensor circuit after you get it running, keep any pigtail repairs you're doing now in mind.
 
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The end is there just very dark color and can't see in photo I have another one of these sensors that hasn't been taken apart but neither of them seem to work when installed I get no spark and the check engine light and up shift light turn on with the key on engine off and they never turn off which my understanding is that means there is no communication to the crank sensor
 
I think the debug is if your upshift light stays on while cranking, you are not getting signal from the crank sensor.

You could have two failed sensors on your hands, I suppose, but I'd want to know for sure it isn't just a harness, or other, issue.

!f you're comfortable around a simple oscilloscope, a single-channel scope is less than $30 on eBay these days, and it can help sniff the waveform off both a crank and cam sensor. There are ways to test both on and off the car, but I prefer on the car, and yes, I know how much work that is, but since cranksensors are now unobtainium, I'd want to be sure one was dead before flushing it down the toilet.

Off the car:
Connect pin 1 to +5V (actually anything from 5V to 20V would be fine)
Connect pin 2 to 0V
Connect a 50K resistor from +V to pin 3.
Using a multimeter, measure the voltage between pin 2 and 3 while you bring a magnet close to the device.

If you see a state change (i.e. a swing from almost 0 to almost the full supply voltage), the device is -probably- working.

-=-
On the car w/scope:
Tap in at DIS for cam sensor, and at connector near cam sensor for crank sensor. DB/O wire, I believe.
Set scope for DC, black to ground, not battery.
Look for a healthy square wave while cranking and/or while running. It doesn't need to fire to see a square waveform while cranking if the sensor is good. If it has a reliable ref. voltage going in and it's ok, it will still output. Be sure it's connected to the main harness.

The computer won't output a ref. voltage if the sensor's circuit isn't complete/no load. You can verify that the computer is outputting ref. voltage to the harness at the TPS or ACT, just be sure to have them connected, key on. Use caution, do not ground the supply voltage...the computer will not appreciate it. I backprobe at the connecter but piercing probes can be used too, just be sure as always to heal the hole w/sealer, liquid electrical tape, etc.. 4.0v ~ 5.0v is good, less is not. I typically read 4.77v, as an example. See the EVTM for testing procedures.

Notes on scope set up:
Reference voltage: 5v scale
Square wave, displayed at 50 or 100 MS. Sample graph in the EVTM as I recall.
 
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I have it off already but the only problem is that I am basically electrically retarded and don't really understand how do that so I'll ask a few people I know and see if they understand that
 
don't really understand how

When that sort of testing is over our head, we're left to mount the sensor up, confirm all connections, be sure the battery is healthy, and see if the upshift light stays on or goes out while cranking.

Doesn't hurt to read codes too ;)

Good luck.

Ken
 
Yeah I've tried all 3 that I have I'm pretty certain that 1 is damaged I can see alot of damage on the sensor itself but all 3 give me the up shift light that won't go away full battery I'll have to try and pull the codes I'm pretty sure I had an issue about a year ago trying to get the codes but I'll try again
 
Crossing my fingers

So I had someone help me test the crank position sensor and I don't think either of us understood exactly what we were doing but I found another sensor for sale which is hard to do but it will be here monday and wends I'll put it on and hope that's my problem ready to drive it I've spent more time trying to fix it then I've driven it 2 years I've owned it and only drove about 300 miles.... Frustrating but I hope this does it
 
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