Diagnosing Crank no start

MercXr7-5speed

SCCoA Member
There is a ton of posts about this. I do apologize about starting a new one. But I wasn't able to find a definite answer.

Cranks, No start, like title says.
Fuel pressure is good at rail
Unplugged cam sensor and still no start
Wanted to fire on ether but not really


Used test light to red wire on crank sensor plug (assume it's pin one), and it stays lit. Never goes out with ignition switch forward and upshift light is on during cranking. Bad Crank sensor correct? I started to use the no start checklist and first test seems like I might have found it. Thoughts?

90 SC Automatic
 
If upshift light stays on during cranking it's usually the crank sensor. Most common reason for crank sensor to fail is because the harmonic balancer is wobbling or broken.
 
If upshift light stays on during cranking it's usually the crank sensor. Most common reason for crank sensor to fail is because the harmonic balancer is wobbling or broken.
Yeah I had two break on my old Cougar back in the early 2000s. Learned my lesson. First I put a used one on. That one broke 1500 miles later so I replaced it with Ford new and a new bolt. Lasted years after that before I sold the car. Previous owner had some work done and the mechanic spliced in the crank sensor. Wondering if the mechanic tried to use the wrong one. The original is in the glove box and it has frayed and cracked wires at the sensor.

Guessing the original went bad and this was the attempt to fix. New sensor will be here tomorrow. I'll put it on Saturday and see what happens. Worst case, I buy a new bolt a balancer next. The test light staying lit on pin 1 to the crank sensor, whether I crank or not, is a weird one.
 
Looked ok when I tapped the starter solenoid. Hopefully the new crank sensor fixes it and when it starts there is no wobble.

Would certainly be easier to do both at the same time. It's a bear getting that sensor out with the balancer on.
 
Looked ok when I tapped the starter solenoid. Hopefully the new crank sensor fixes it and when it starts there is no wobble.

Would certainly be easier to do both at the same time. It's a bear getting that sensor out with the balancer on.

Yes it is difficult. You can ditch that plastic cover with timing marks. There are timing marks on the balancer, so it really isn’t necessary.
 
Car is alive!!!!! Crank sensor was completely the wrong one. Previous mechanic tried to splice a different one in. Doing regular maintenance now. Have to wait a few weeks for the antique tag to come from PennDOT. So new tires, brakes, belts hoses etc in the meantime n
 
Had the car out on the road today. She's definitely tight. Little problem in the rear I need to investigate. When I take off from a stop under anything more than 1/4 throttle something is slipping (or so it feels) in the rear right hand side. Once it's moving, I can hammer down and there is no issues. 1000013646.jpg
 
Doesn't sound good at all. Drive axle splines slipping in the diff or wheel hub or the diff itself is bad?
Sounds like it'll leave you stranded in the near future.
 
Doesn't sound good at all. Drive axle splines slipping in the diff or wheel hub or the diff itself is bad?
Sounds like it'll leave you stranded in the near future.
I'm not really driving it now. Just wanted to see what it needed work wise before I start buying stuff. It will need pads and rotors to be highway worthy. Going to have to pull the rear wheels and start inspecting rear components. I'm figuring I'll need axles at the very least.
 
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