Originally Posted by Montego Murph

Hey all,

There are a bunch of posts floating around that can be summarized like this:

Question:
"My I30/Max has a hard time starting... cranks and cranks, sometimes makes a clunking noise... but eventually sputters to life"

Response:
"You should replace your crankshaft position sensor -- the one closest to the oil filter. That one goes out and causes this condition."

For what it's worth, I was participating in this one. There's a youtube link in there to the condition described if you want to say "hey, that's my car too!"
http://forums.maxima.org/5th-generation-maxima-2000-2003/636313-starting-problem-how-determine-sensor.html

HOWEVER...

Don't go buying a new sensor JUST yet. Check this out first.

I removed the sensor (one 10mm and phillips screw for the weather covers, and 2 10mm bolts holding on the sensor. Push the green doodad IN until it clicks, then pull the sensor wire off. Remove the 2 10mm's.

If you'll all open your hymnals to chapter EC, page 521, it says you can use a multimeter to test for resistance between the two contacts. They say it should be 470-570 ohms at 68 degrees F. Also they tell you to check the little nub at the top for chipping.

So I'm sitting at my desk fiddling with my multimeter and testing the contacts, and I get 800 ohms of resistance. Still a little more than expected, but doesn't seem too tragic. If it were adjustable, maybe, but...

Then I start looking at the little nub at the top and it's completely surrounded with road gunk, greasy dirt, maybe some metal shavings, who knows what. The nub appears to be magnetic.

I took some MAF cleaner and blasted the nub, then took a junk cloth and scrubbed it clean, got my fingernails in there and cleaned the groove.

Tested it clean and I came out to an even 1000 ohms of resistance. I have to admit that I'm not sure what it means, but if it wants about 500 ohms at 68 degrees, and it's about 110 degrees everywhere outside right now, maybe there's some variance. Truth is, I have no idea what the ohms have to do with anything at this point. I've never seen an ohm anyway so I wouldn't recognize one if you handed me a bagful of them. Tell you what, ignore this whole paragraph.

After cleaning the sensor, I reinstalled it, cranked the engine, and the starting problem is GONE. It's like a brand new car all over again. No more of this three tries at 5 seconds each while people say "dude, what's up with this car?"

Of course this is only after about 20 minutes of testing and quick errand running. it may very well blow up tomorrow. I'll keep everyone posted if something fails, but no news is good news.

In the meantime, CHECK AND CLEAN the sensor before dropping 80 bones on a new one!

Originally Posted by Maxima 97 SE

heres what i did today. I took my sensor off and cleaned it with isopropyl Alcohol. I just dipped the whole sensor in their and cleaned the outside and cleaned the part of the engine that the sensor connect to which was really greasy and now its clean and now it hopefully wont leak oil and i cleaned the contacts of the sesnor with q tips and for the wire i sprayed a bunch of isopropyl alcohol and cleaned out all the oil and it made a big difference in starting. It starts in a flash even though it didnt have any problems starting or with cranking it just made it seems a little smoother. I used electrical tape to tape the wire and the sensor so that it prevent the oil from seeping in to the contacts of the sensor and the wire. For the cranking problem i know that if a maf sensor is bad it will cause that too. My maf went bad one time and it caused the car to crank about twice before starting and i put in a new updated maf that i had at home which was an oem maf and the problem was gone.