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View Full Version : Crank Position Sensor (OBD) ?????


danes
06-28-2007, 10:12 AM
So my s14 is acting a fool with the chitty acceleration, loss of power and hesitation. It's a 96 with a stock ka besides the exhaust. I checked the ECU code and it was 82. To follow someones advice I replaced the maf and that did NOTHING for the car. So has anyone had to deal with this code or OBD or anything? Can I just replace it?

I hope so.

Danke in advance

orion::S14
06-28-2007, 11:09 AM
82 is the OBD crank pos. sensor...used for NOTHING except diagnosing misfire.

That's NOT your problem.

If the car idles and revs...then it's not the MAF.

I'd start with tune-up stuff like plugs and wires...

Check the TPS (used by the ECU to determine timing advance...if it's acting screwy, you'll get e very slow and _flat_ feeling KA24)

..then fuel pressure. if you have a dieing pump, it'll be super lean and SLOW.

Etc, etc...

- Brian

danes
06-28-2007, 11:18 AM
Thanks alot man, I'm gonna check on the tps. I forgot to mention though that when you unplug the maf the car runs fine and idles smooth. well besides the fact you can't rev it past 3k.

DoctorMuffn
06-28-2007, 03:42 PM
82 is the OBD crank pos. sensor...used for NOTHING except diagnosing misfire.

That's NOT your problem.

- Brian

Are you sure?
First off where did you find that OBD I code 82 for a 96 S14 is CKP sensor? And if it's a 1996 car (the year that OBD II was mandated to take effect federally) why aren't we looking for OBD II codes?

Also keep in mind that Speed Density, Density Speed and MAF Systems all require the signal input from the CKP sensor to tell the engine it is underway and should be firing and pulsing fuel. The distributor signal is used to determine exactly which cylinder to be firing at what time in conjunction with the CKP sensor signal. And a CMP sensor signal is even more useful when determining exactly which port to inject into if the engine is designed with sequential (as opposed to bulk/batch/group) port injection. CMP sensor input will also determine which cylinder to fire if the engine management system is DistributorLESS.

However, all of these are based on your CKP sensor signal input first to determine engine speed and often relative position.

Nismoknightska-t
06-28-2007, 04:16 PM
I dont even run the Crank Position Sensor in my 97 due to the fact that it was auto and I swapped in a 91 tranny..

So that is not your problem..

projectRDM
06-28-2007, 06:37 PM
Are you sure?
First off where did you find that OBD I code 82 for a 96 S14 is CKP sensor? And if it's a 1996 car (the year that OBD II was mandated to take effect federally) why aren't we looking for OBD II codes?

Also keep in mind that Speed Density, Density Speed and MAF Systems all require the signal input from the CKP sensor to tell the engine it is underway and should be firing and pulsing fuel. The distributor signal is used to determine exactly which cylinder to be firing at what time in conjunction with the CKP sensor signal. And a CMP sensor signal is even more useful when determining exactly which port to inject into if the engine is designed with sequential (as opposed to bulk/batch/group) port injection. CMP sensor input will also determine which cylinder to fire if the engine management system is DistributorLESS.

However, all of these are based on your CKP sensor signal input first to determine engine speed and often relative position.

You have absolutely no fucking clue what you're talking about, period.

On some cars, Mitsubishi for one, this may be true, but not on any Nissan product. The crank position sensor is used only for onboard diagnostics of misfire, taken right out of the FSM and typed by me at least a dozen times a month. It's not found in the distributor, it's located on the bellhousing and uses a magnet to detect flywheel rotation. It has absolutely no effect on engine firing or operation and does nothing at all when unplugged, damaged, or removed entirely. The CPS is only found on 95+ 240s (96+ on all other Nissan models), so in your theory anything 94 and under doesn't have a CPS, so it doesn't run. Brilliant.
The CMPS (camshaft position sensor, located in the distributor) signals the ECU for the correct timing.

While I can appreciate anyone willing to answer a question, learn what forum you're on. Your above post is only going to confuse the 400+ members who are too stupid to read an FSM in the first place, making them go out and buy a unnecessary part to fix a problem that's unrelated to that part, forcing them to come back and start another thread that's completely useless and could have been avoided had the right information been posted beforehand.

And if you're still looking to argue, drive down and count the nearly three dozen cars I've worked on that no longer have a CPS, all running fine and without any sort of issue that would be related to what you've written above.

orion::S14
06-28-2007, 07:38 PM
Are you sure?
First off where did you find that OBD I code 82 for a 96 S14 is CKP sensor? And if it's a 1996 car (the year that OBD II was mandated to take effect federally) why aren't we looking for OBD II codes?

Also keep in mind that Speed Density, Density Speed and MAF Systems all require the signal input from the CKP sensor to tell the engine it is underway and should be firing and pulsing fuel. The distributor signal is used to determine exactly which cylinder to be firing at what time in conjunction with the CKP sensor signal. And a CMP sensor signal is even more useful when determining exactly which port to inject into if the engine is designed with sequential (as opposed to bulk/batch/group) port injection. CMP sensor input will also determine which cylinder to fire if the engine management system is DistributorLESS.

However, all of these are based on your CKP sensor signal input first to determine engine speed and often relative position.

I won;t add too much more...Russ covered it for me.

But I will reiterate part of his post...the CPS is on the bellhousing, and is used ot doagnose misfire.

The CAMSHAFT pos. sensor is built into the dizzy on a KA, and would trip a code 11 if it were faulty.

As to where I got the codes...from the FSM. I also have a copied-and-pasted list on my website: http://www.ka24development.com/ecu_codes.html

- Brian

DoctorMuffn
06-28-2007, 08:20 PM
It's very possible that I don't know everything. Thanks for your responses to my questions and suggestions. I'll check into it a little more.

bobbyc1011
09-03-2009, 12:02 PM
If the CKP sensor is busted will that also cause the fuel injectors to not fire? Cylinders 1+3 on mine have no electrical pulses going to them, but the car will keep running on cylinders 2+4.

bobbyc1011
09-03-2009, 12:17 PM
Or do i have a bad ECU 1990 Nissan stanza (KA24De)

projectRDM
09-03-2009, 03:59 PM
Or do i have a bad ECU 1990 Nissan stanza (KA24De)

If the CKP sensor is busted will that also cause the fuel injectors to not fire? Cylinders 1+3 on mine have no electrical pulses going to them, but the car will keep running on cylinders 2+4.

Did you even read anything above? You brought up a two year old post to ask two questions that are already answered right above you.

The crank position sensor is only found on 1995-1998 model 240SXs. Second, it does ABSOLUTELY NOTHING except signal the ECU to diagnose misfire.

Your problem has nothing to do with this topic. Try again in a new thread.

danes
03-11-2012, 10:42 PM
Lololol. Turned out to be the fuel hose that connects the fuel pump to the hard line had disintegrated. In case someone tries to use this thread for their own problems.