1996 Maxima P0400 caused by exhaust leak?

I have a 1996 Nissan Maxima with 205xxx miles on it. The check engine light is on and when I read the codes I get:

P0400
P0325
P1335

there's another I can't remember right now, but the codes call out knock, egr, IAT, the carbon canister valve/solenoid by the gas tank.

I'm only focusing on the EGR right now which is why I'm not more specific with the details of the other codes.

The car runs smooth as hell, sometime I have to look at the tach to tell if it's running or not.

Recently the crank pulley separated itself from the harmonic balancer, so I replaced it. in process I removed the crank position sensor (or what I assume to be the crank position sensor) little black thin near the crank that's slightly magnetic. I was wondering if there is any initiaization sequence or any special way I have to put that back.

before I had the codes cleared (I'm going to read them again tonight, hopefully crank sensor isn't in it this time) if I shut the car off and tried to start it within an hour, it would not start for a while, and after the 3rd or 4th 15second crank it would start.

now I pulled up the egr diaphram and the car stalled, supposedly that means the EGR is good? when I went to autozone they told me the EGR code could be from the exhaust leak.

Is this possible? or would it be a bad BPT? the exhaust leak I believe is right before the flex pipe under the car (I just got the car sunday and haven't really had a chance to check it out yet).

I plan on fixing the leak anyway but was curious to know if the exhaust leak might have anything to do with it.


Thanks!

I wasn't aware that vehicle had a positive feedback EGR on it. They're not too common, so Id say, no. Standard EGR valves don't care how much back pressure there is. Check that the EGR is being actuated. And post ALL codes.

Codes were

P0400
P0440
P0325
P1335

But after I erased them, the only code that comes back (only one day of drive, about 30 miles) are:

P0325
P1335

So I went to nissanhelp.com and downloaded the ef & ec section of the shop manual, it seems like the crank sensor is not reporting right for the first few seconds of cranking?

I'll let you know if any of the other codes come back, their driving cycle hasn't been completed yet.

HI ¡

For the EGR code, be sure the EGR is valve is clean and sealing properly into the intake manifold. Also check if it is having vacuum in its vacuum hose when energized; check for broken vacuum hose.
IF all of these is correct then could be the EGR solenoid, check if the EGR solenoid wires are having voltage (maybe your EGR-solenoid is not functioning anymore and you will have to change it).

For the CKP code; if you were working on the armonic balancer maybe you didn´t installed well the ring that is mounted in the crankshaft or also could be dammaged when installed, be sure the teeth from the ring are not broken or dammaged (if one of the teeth is dammaged you will then noticed the CKP failure and code).

For the P0325 (knock sensor) you will have almost to change the knock sensor for new one. (I think it is expensive).

For the EVAP code; start by checking your fuel Cap and losen or broken Canister hoses (they are located near the fuel tank)

I agree, the first thing I would look at is the crank sensor and the ring this sensor "looks" at to determine what the cranks position is.

You'll have to look in the service manual and get the the test specs for the sensor. It may have obvious physical damage from you changing the pulley though.

I was trying to get away without spending any money, but after visual inspection of the crank sensor, the whole top was broken off.

because I had a pulley separate from the harmonic balancer and fly off the car...hehe...

so that's fixed now, but I still have the EGR, knock, and Evap code. I now also have a p0136 which is rear o2s. When I use the scan tool I got to view sensor data it only shows me .010v on that sensor, going to check to make sure it's plugged in today.

I got the shop manual, turns out if you join nissanhelp.com, you can download one part of the shop manual free each day.