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Lou P
Lou P, ASE Certified Technician
Category: Nissan
Satisfied Customers: 4087
Experience:  15+ years experience in the automotive field on all types of vehicles with access to diagrams and repair info.
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I am working on a 1994 nissan maxima 3.0L. I have a CEL

Customer Question

Hi i am working on a 1994 nissan maxima 3.0L. I have a CEL on but i do not have a scan tool to check the codes. There is a diagnostic port on the Left Hand side of the steering wheel but i do not have the attachment to fit it. Is there any way i can get codes from this vehicle without a scan tool?
Submitted: 10 months ago.
Category: Nissan
Expert:  Lou P replied 10 months ago.
Hello, here is the way to check the codes on the early Nissans. hope this helps. Lou P. Please take a second and click the stars at the top of the screen to rate me so i may receive my credit , 5 stars is ideal , please request me in the future.Keep in mind then when you rate it does not end our conversation. you can still return here to me for follow up information if needed, Lou P.
Customer: replied 10 months ago.

Okay so i found the adaptors for the scan tool and i was able to get 3 codes. Code 34- Knock Sensor Circuit. Code 11- Crank angle sensor. Code 21 Ignition Primary voltage Malfunction. With these codes, which should i diagnose first? Probably ignition coil problem because it could cause the other codes to trip?

Expert:  Lou P replied 10 months ago.
i would start with the crank angle, that may be a timing issue. or what i would do is erase the codes and see what comes back first, that is how we approach in the shop, some issues can set codes and never happen again so you dont want to chase what we call a GHOST code.
Customer: replied 10 months ago.

okay! now the code from the scan tool is code 11 crank angle sensor. On alldata it is saying camshaft angle sensor? Am i going after the cam or crank sensor?

Expert:  Lou P replied 10 months ago.
Let me check, i still have your info up.
Expert:  Lou P replied 10 months ago.
crank position sensor
Customer: replied 10 months ago.

Okay after clearing the code and driving the vehicle the only code it is coming up with is code 34 knock sensor. The problem i am having is it is running rough and hesitating. I have checked the cam and crank sensors resistance and they check out fine. Any other advice on how to deal with this?

Expert:  Lou P replied 10 months ago.
is the engine knocking or pinging, if not then ohm the knock sensor to ground, you could have high or no resistance, or the knock sensor could be the issue. knock sensor codes are either sensor, poor mounting ground, wiring or ecm, there is not much to a knock sensor circuit.
Customer: replied 10 months ago.

Can the knock sensor cause a rough running engine?

Expert:  Lou P replied 10 months ago.
it can,. ill explain
Expert:  Lou P replied 10 months ago.
if the knock sensor is activating that will retard the timing, it can retard it far enough to cause a misfire and rough running, so the fastest test would be to unplug it and see if it still runs bad, it is possible you have 3 issues , crank sensor (or bad timing) a bad coil or distributor and a failed knock sensor, the car is old enough that i would not put it past it to diagnose all 3 individually.