atomic_fungus (atomic_fungus) wrote,

#7108: Maybe the crankshaft position sensor...?


I'm running out of ideas. I made a list of the sensors that are used to determine how much fuel to put in the engine, and when; and then I consulted the Internet YET AGAIN.

The crankshaft position sensor (CKP), in the XJ Cherokee, is a common culprit in these kinds of cases. Typically when they fail the vehicle just fails to start at all; but having read and read and READ AND READ about "low speed stall/stumble" problems, and having run through the other obvious usual causes, I'm left with this one.

It turns out that a failing CKP can cause low-speed stumbling etc. It may still be capable of sending a signal to the computer, but not quite good enough for the computer to run the engine properly. Reading through a description of troubleshooting made me think about this particular gewgaw.

It mentioned, for example, that if you disconnect the thing and try starting the truck, the computer will act as if you'd reset it. The truck won't start, of course, with the CKP disconnected, but when you plug it back in, it'll run. At least, for a while.

I've been noticing that the truck has the issue, most commonly, when the engine is in closed loop--thoroughly warmed up--and a lot of the discussion I saw on-line about it described trucks which would run when cold but die as soon as they got warm.

These sensors are pretty common failure points, too. If I'm right this one's never been replaced, and 205,000 miles is a good long time for one to last. Needing replacement somewhere between 100,000 and 130,000 is more common.

*sigh* Of course, every time I've thought I had the solution, it fit the symptoms perfectly, and turned out to be wrong.

There's a simple test, though: unplug the sensor and check resistance on pins 2-3. Anything under about 8k or so means "bad sensor, replace". Unless I miss my guess the sensor is a reluctance sensor and looks for precision holes cut in the flexplate, and low resistance means some kind of short circuit in the thing. It is not only possible but fairly common for the CKP to fail such that it doesn't really work, but the computer doesn't really know it, so there's no diagnostic code.

And so, when I got home, I set out to do just that test.

Now, on older model Cherokees, the plug for the CKP is up top by the fuel injector manifold. It's very easy to find, very easy to unplug, very easy to probe resistance. Replacing the CKP is more difficult, but just the diagnostic part is easy-peasy. This was too convenient for Jeep-Chrylser, though, so they moved it down underneath the truck, alongside the transmission, "for conveniece and ease of service." (YES! THAT IS SARCASM!) Now, to do the job I want to do, I need to drop the front f-ing drive shaft in order to have room to work.

*sigh* I've decided simply to replace the damned thing. Not tonight! Saturday. If I'm going to have to go to all that trouble to test it, I might as well just replace it outright. New one's about $30-ish from O'Reilly's, so what the hell.

Noticed something else while I was down there: I think the Jeep has a rear main seal leak. So that means that if I do end up "massaging the jalopy" this summer, and doing all the sheetmetal work etcetera, then I'll want to drop the transmission and replace that seal, too.

And maybe get a gander at the transfer case. It's made a bit of noise for quite a while--maybe if something's wrong with it I could get a rebuild kit for it.

But that's if I can fix this problem first. *sigh*

* * *

Pretty high confidence that the Wuhan Virus escaped from a Chinese biological research facility which is why they wanted to cover it up.


1) no bats in the wild that carry the disease within about a thousand miles of Wuhan, nor at the market which was literally just down the street from the lab
2) worker at the lab has been unpersoned after she was involved in a "blood spray" incident working with specimens of said bat that carries the virus
3) China engaging in a massive cover-up as soon as people started getting sick, and this probably happened in September or October rather than December
There is increasing confidence that the COVID-19 outbreak likely originated in a Wuhan laboratory, though not as a bioweapon but as part of China's attempt to demonstrate that its efforts to identify and combat viruses are equal to or greater than the capabilities of the United States, multiple sources who have been briefed on the details of early actions by China's government and seen relevant materials tell Fox News.

This may be the "costliest government cover-up of all time," one of the sources said.

The sources believe the initial transmission of the virus--a naturally occurring strain that was being studied there--was bat-to-human and that "patient zero" worked at the laboratory, then went into the population in Wuhan.
And as I said in (2), she's been unpersoned. Look at the web site for the lab and her picture is gone. Despite China's "social credit" system no one can seem to find the woman. $5 says she's dead (of the disease) and burned to ash and buried in an unmarked grave.

If this is true, China's in for a world of hurt. Everyone is going to be pissed off at them, and that will mean punitive tariffs and millions of people deciding not to buy things made in China if they can possibly help it.

* * *

I love it when liberals run afoul of the horseshit they've spewed out all over the rest of us. Of course, when they do, they get indignant about it, and that just makes it that much better.

A city commissioner went to buy a gun and was mad when he couldn't take it home right away:
He DEMANDED to know "Why can't I take it now? I need it now." He was not happy to hear that it was the LAW. He then explained, "I hate guns and I have supported gun control in the past but this is damned ridiculous. When you need a gun you should be able to get it."
What he means, when he says "When you need a gun...," is actually, "When I need a gun I should be able to get it!" He's just fine with everyone else having to wait for their guns, because they're all criminals and lunatics, but he should be exempt from the law because he is, after all, a politician!

Man, if there is anyone who shouldn't be allowed to own guns, it's a Democrat.

* * *

Democrats are abusing their emergency powers to disrupt religious services of Christians and Jews, but not muslims. Of course.

And of course the LGBTITNAHGBBQWTFOMG crowd is all over the relentless persecution of the religious.
This person is absolutely giddy about people dying of a respiratory virus.

The numbers of elderly and infirm dying is just the greatest thing for this pile of human garbage, and he can’t wait to dunk it on people.
Democrats are evil and leftists are evil. That's really all there is to it.

* * *

That inch of snow we got yesterday apparently was the root cause of a 50-car pileup on a local expressway, because IDiOT couldn't be bothered to send out salt trucks.

Way to go.

* * *

Well, I need to cook some dinner and think about my next move.

  • #7866: YE CATS that's a lot.

    This is why we need to be concerned about Evergrande, the chinese real estate company. "Real Estate in China is valued at 12 TIMES the entire…

  • #7865: It rained, but not on me.

    Beautiful--ridiculously nice--gorgeous weather today at lunchtime, so I rode the bike back to work. Getting on towards quitting time, the sky…

  • #7864: What--a FOUR STAR ADMIRAL? What the hell?

    Ace's Quick Hits today--you have to scroll down a bit but apparently the health and human services secretary has been sworn in as an admiral. I…

  • Post a new comment


    default userpic

    Your reply will be screened

    Your IP address will be recorded 

    When you submit the form an invisible reCAPTCHA check will be performed.
    You must follow the Privacy Policy and Google Terms of use.