AntGVR4

I've been having this problem for a while and so far NO ONE has figured this out

Approximately 4 weeks ago I put a WSP ypipe on my car. Upon installing the pipe i disconnect the battery for 4 hours and performed the install flawlessly at my cousins shop. I drive the car for 1 week putting around 300 miles on the car and I head to the track the week after. Before I put my ypipe on my best time was 15.6 @ 86.7 mph. That day I made 3 runs at 15.8-16.0 and the trap speeds were 84-85 mph. The fact that trap speeds were lower showed that it couldn't be my launch, I just lost top end. I also reset my ECU that day and drove around and it did nothing.

I visited my cousins shop today and put the car on the lift, the pipe is fine and everything looks good. I also called Dallas at WSP and he recomended I check my O2 sensors and cat. He also recommended I ask Daniel Martin for his take on this.

My next step was to hook up my cousins scanner to my ECU. It showed P0325 Knock Sensor #1 Malfunction
I checked all other readings from 02's to idle speeds and everything seemed fine.

We proceeded to call nissan about the code and they said it was a common code and just to ignore it, and that even if we reset it, it would just come back, and that all maxima's had that code.

The car drives fine in the city (it is an auto) and first and second gear pull fine, it's once the car shifts into third it loses all power, there is no pull in 3rd gear.

To test this I did a highway pull with another maxima last night who had everything I have minus the ypipe, and from 60-90 mph he pulled by an entire car on me, whereas it should be me pulling from him.

My next step will be to check the fuel filter.
Could the 02's possibly need changing?

Any suggestions would be helpful.


Ant

Sprint

iTrader: (10)

Buy a 5spd..

Jeff92se

iTrader: (82)

I don't know about that all maximas have that code thing. Reason why I say that is becuase I haven't seen anyone else complain about that code. If what Nissan was saying was true, then we would have alot more people mention the knock sensor.

Is your car under warranty? If so, I can see the dealer trying to weasel out of the work. If the knock sensor is anywhere near the 3-gen VE30DE one, that you have to pull the upper and lower intake manifolds to get at it. (pita)

But it could be the wiring harness. This you can get to w/o removing anything(I think). Try disconnecting it and cleaning the terminals. Reset the ecu and see if the performance comes back or if the code pops up again.

If the knock sensor is indeed faulty, it could be pulling the ignition timing back in 3rd gear. I suspect 3rd gear puts the most "load" on the engine and thus a timing pull back would really hurt the engine's performance.

Ants97SE

I know this sounds obvious, but make sure your knock sensor is plugged in. If it's not it will retard the engine timing a lot and you will lose a lot of power. My friend who just had a 99 engine swapped into his 96 said he lost power until he found that the shop had not plugged in his knock sensor. Once that was in, he felt his power come back again.

Daniel B. Martin

Diagnostic Trouble Code P0325 is the same as DTC 0304 which points to a problem with the Knock Sensor. The KS is attached to the cylinder block. It senses engine knocking using a piezoelectric element. A knocking vibration from the cylinder block is senses as vibrational pressure. This pressure is converted into a voltage signal and sent to the Engine Control Module (The computer).

This malfunction is detected when an excessively high or low voltage from the KS is entered to the ECM. Possible causes include...
- the harness or connector (The KS circuit is open or shorted).
- the KS

The KS may be checked with an ohmmeter.

1) Raise the hood. View the engine from the driver's fender. Look into
the deep valley between the cylinder banks and below the intake manifold.
Identify the KS as a black item fastened to the block by a single vertical
bolt. A wire harness wrapped in black leads toward you, out of the valley.
That is the KS sub-harness.

2) Follow the KS sub-harness to it's nearest connector. This is connector F121.
It is located near the upper right-hand corner of the valve cover of the forward cylinder bank, as viewed from the front of the car.

3) Disconnect F121. You have to do a "press the latch and wiggle and
pull" to disconnect it. F121 has only two pins; if you see more than two
pins, you have the wrong connector. Use a digital ohmmeter capable of
measuring more than 10 Megohms. You want to measure the pins of F121, not
the sockets of the matching connector. Measure the resistance between a
good ground (such as the battery negative terminal) and pin #2 of connector
F121. On my car this is the highest of the two pins, the one closest to
the front of the car. The factory spec is 500 - 620 Kohms.

The manual says you have to remove the intake manifold to replace the KS. However, I think that a person with good dexterity and a 10mm ratcheting box wrench could replace the KS without disturbing the manifold.

AntGVR4

I checked the Knock sensor wiring harness. There is only one wire coming out of the Knock sensor connector, where i can clearly see there should be two. The one wire that is clear is there but the black wire with the yellow stripe that is present at the other end of the Knock sensor wire connector F121 is not connected at the knock sensor.
I am now going to attempt to pull the connector off at the Knock sensor and fix it there.

Is that black wire from the Knock sensor just a ground?
If so I can just connect a ground to F121 and see if that is the problem before I spend the time to fix the connector or get a new one.

Ant

Daniel B. Martin

I can't answer. My car doesn't have a black wire, nor does my '99 factory service manual show one.

Kenneth

iTrader: (8)

whenever i reset my ecu, the knock sensor code goes away. dono why

AntGVR4

As far as I can see there should be two wires coming out of the Knock sensor, however there is only one, and I can see where the other one should be. I just tried to take the connector at the knock sensor off but I can't. The knock sensor is one piece and it seems that I have to change the entire sensor to fix the problem.

Any one have an idea as to how much a Knock sensor costs for a 95 Maxima?
I would like to take care of it asap.

Ant

Daniel B. Martin

AutoZone.Com lists Wells #SU2074 for $265. This is surprisingly high.
Check with one of the Nissan dealers who sell parts at a discount.

Brown and Brown Nissan, Tempe AZ
Parts department: 800-237-0003
http://www.brownandbrowntempe.com/parts_form.cgi

Courtesy Nissan, Richardson TX
Parts department: 800-527-1909
http://www.courtesyparts.com/

Garrands Nissan , Plattsburgh NY
(advertises genuine Nissan Parts at 25% off list price.)
Quote line: 800-339-2922
info@garrands-nissan.com

West Broad Nissan, Richmond VA
http://www.westbroadnissan.com/nissanparts.htm

Vester Nissan, Clinton NC
1-800-572-2005

When you contact any of these dealers be sure to mention you got their name from the Maxima forum.

Ants97SE

You might also want to check http://www.nissanautoparts.com

If you have the part number you can type it in and look it up on-line. A lot of their prices are cheaper than most dealerships.

Synki

Gee i wonder who this was.

I sure hope this fixes the prob. I wonder if i have this prob too?

Daniel B. Martin

All Maximas have that code? Mine doesn't. I distrust such sweeping generalizations.

AntGVR4

It did seem peculiar to me that no one else on the BBS has mentioned that code before.
Unfortunately I doubt I will be able to change the knock sensor until next friday because final exams start tommorrow and I will not have a chance to go home until then.

Thanks for the help and I will post my results when I change the sensor.

Ant

AntGVR4

Daniel : I check the knock sensor and there is approximately 600K ohms between the pin that closer to the front of the car and a ground .. Does this mean the knock sensor is fine?

My question is:
How many wires should there be AT the knock sensor? As in how many wires should be coming out of the sensor?

Reason is i spoke to a friend of mine who is an ex-nissan technician. He said there might be only one wire coming out of the sensor?

He also said a common problem on a car with high mileage is that the entire ECU harness comes loose or goes bad?

Ant

Daniel B. Martin

A dealer using the CONSULT electronic tester can do a more thorough test than what the home mechanic can do with only an ohmmeter. However, it is likely that your KS is good.

According to the factory service manual it is one wire, but it is a coaxial wire so there are two conductors. The co-ax is similar to the TV cable wire but with a much smaller diameter.

I never heard of this, so it can't be "a common problem". I don't know what he means by "goes bad". A harness is not a consumable item like brake pads. It is not something that is expected to deteriorate.

radiohead75243

Though there appears to be no discernible loss in power, I have had 7 instances within 8 months where the diagnostic Codes 0304 (Knock Sensor) and 1003 (Park/Neutral Position Switch)have appeared, always together. Each time I have manually extracted the diagnostic trouble codes and reset the Control Module, but I have grown increasingly agitated. Trophy Nissan suggested I ignore the codes and reset the Control Module, indicating that Code 0304 is common. As for Code 1003, I have a 5-speed and it doesn't start unless the clutch is depressed, so why would I be getting that code?

Perhaps I am experiencing a problem with the Control Module. I would appreciate any guidance which may help to resolve my continued problems with the these codes and/or the Control Module.

Daniel B. Martin

The '99 Maxima factory service manual shows that Engine Control Module terminal 27 is connected to ...
- (automatic) the Park/Neutral Position switch.
- (5-speed) the Reverse Position switch. This part is also called the Back-up Light switch.

Verify that both back-up lights are functioning. Replace any burned out bulbs.

Check the wiring and connector of the Reverse Position Switch on your transaxle case. Identify connector F32 which has four terminals in a gray plastic shell. This connector is easy to see but not so easy to reach. With the hood open, look down at the transaxle with your line of sight passing down behind the black plastic engine air intake duct. You will see the starter motor. Connector F32 is near the starter motor, just one inch away, toward the rear of the car.

Disconnect F32 and observe that the connector half which leads toward the Reverse Position Switch has four terminals. With the latch oriented at the 12 o'clock position there are two rows of two terminals each. The upper row is numbered 1,2 (right to left). The lower row is numbered 3,4 (right to left). With the transmission in Reverse there should be continuity between terminals 1 and 3. With the transmission in Neutral there should be continuity between terminals 2 and 4. With the transmission in any other position there should be no continuity. Terminal 4 should have continuity to body ground, regardless of transmission position.

AntGVR4

I guess this puts me back at the drawing board..
But if my Knock Sensor is measuring correctly why do i get a knock sensor error code ?

Any other ideas on what might be wrong?

Ant

Daniel B. Martin

The ohmmeter test is useful to condemn a bad KS. However, passing that test does not guarantee that a KS is good. There could also be a defect in the harness between the KS and the Engine Contol Module.