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What did I do - 2001 won't start - crank sensor?

5K views 10 replies 5 participants last post by  habbyguy 
#1 ·
Hi Forum Experts!

I'm perplexed and desperate.... I changed the much maligned power steering pump inlet o-ring yesterday and now the car won't start. It cranks just fine, but absolutely no sign of ignition. Strong gas smell, removed the plugs which were wet. Plugging one back in to the coil and holding it against the block I could get a spark while cranking the motor. So, there seems to be both spark and fuel.

I think that the crank sensor connector is right next to that pump inlet - could I have damaged a wire? I was super careful with trapping any fluid that came out. However that 10mm nut is really tricky to get at and I could have moved that connector around a bit. I have taken the connector apart and put it back together; it looked it fine shape - no corrosion. Another thing I did during the o-ring change - I thought I might have to take off the ps pulley for access and moved that around quite a lot while I found a place to wedge a bar through the holes to hold the pulley while I undid the nut.

One indicator that it could be the CPS or its wires - no movement of the tach needle when the starter is cranked. There are no codes on the OBD.

I'm going to change the plugs this morning, just because they are out and it's time, but I don't think that's the problem.

Has anyone ever experienced this or got any advice? Do these wires ever go bad? There's a protective sheath over the top side of the connector wires where there was a sharp bend in the wires - a point of failure after 150,000 miles? I'm reluctant to cut that to look since it probably helps heat protection, but maybe that's a next step?

Thanks to all for any words of wisdom!
 
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#2 ·
Sometimes this happens to me when our 2005 MDX just suddenly won't start, but cranks just fine. I notice this usually happens when you turn on and off the car really quickly - like when you move it to the garage to fix it. Put humpty-dumpty back together and go to start the car. While it's cranking, pump the gas pedal a few times. See if she starts to try and get going.

I'm not quite sure why this happens. Maybe the engine floods itself or the fuel injectors get into a funky state, I'm not sure, but you're describing something that I know mysteriously happens to me sometimes.

Good luck.
 
#3 ·
That's not the CKP (crank) sensor. The fact that you are getting work and fuel means that the CKP, which is much lower down, is working.

Do you have a scan tool to see if there are any codes stored?
 
#4 ·
Thanks, SuperTech (and to Cloud). I plugged in my code reader, found nothing. New plugs now, no difference, of course. I did try a pedal-to-the-floor suggestion, also no difference. A tech at the auto parts store endorsed the crank sensor/wire idea. All indications seem to point to a tow to a shop that has the tools to pinpoint the problem, unless I want to be brave and cut that sheath covering the wires leading to the harness, on the chance I can then see the issue.
 
#5 ·
Don't cut anything. Any decent diagnostic technician isn't going to be working at a parts store.

I am 100% sure your crankcase sensor is fine. Again. You have spark and you have injectors firing. Absolutely not possible if the crank sensor is non op.

Now what could have been damaged doing a P/S pump, and assuming your engine has one, is the camshaft sensor. Unlike a crank sensor, if a cam sensor is bad, it will still have spark and fuel. But may run poorly if it even runs at all since the cam sensor pretty much is used by the PCM to modify base fuel and spark timing settings that are using the crank sensor.
 
#7 ·
Update: Not the crank sensor, but in fact a timing belt screw-up caused by turning the engine from the power steering pump pulley when I thought I was going to take that off to get at the inlet nut. By a complete miracle it seems that no valves crashed into any pistons and the car is back on the road with a new timing belt tensioner. $500 to replace a $0.50 o-ring! Grateful that the damage was not greater. Lesson learned.
 
#9 ·
I turned the ps pulley and its belt to find a place to wedge a bar through its holes so I could undo the nut. That de-tensions one side of the timing belt and it jumps. And then I didn't even take the pulley off when I found a thin wrench that could work around it to get on the nut. An indicator that I should have noticed: the engine cranked very easily because there was no compression!
 
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