I am working on my son's 2002 Pathfinder and it is throwing the codes listed above.

After reading many of the posts about these codes we replaced both of the 'radial' sensors and the 'axial' sensor in the timing cover with no change to the codes.

We considered replacing crank sensor at the back/underside of the engine. However, the one mounted there resembles this one: https://www.autozone.com/engine-managem ... 730122_0_0 ($232)

I don't mind shot-gunning a few $40 sensors in an older car, but we don't seem to be making much progress and now it's getting serious!

The car usually runs fair to well, but sometimes goes into a reduced power mode. It has thrown codes for catalytic efficiency etc, but never any crankshaft codes.

The two radial sensors were ordered by my son from Amazon - theoretically Dorman and the third sensor was from Autozone.

So, it seems like there are a few options:
- both solenoids are bad?
- the old sensors and the new sensors are bad
- something else, such as the crank sensor or ?? is causing the issue.

Any suggestions where we start next?

I've never seen a P1140 or P1145 masquerade as anything but a sensor issue, the ECM's are good at sorting it out and IVT solenoids or phaser issues won't cause them. I have (occasionally but rarely) seen crank sensors that are weak but not dead cause the ECM to incorrectly blame the cams. However, the WD shows all three sensors share a common ground at F20, one of the two 6mm (10mm head) grounding screws under the LHF of the engine cover. Since even the 2-wire axial sensor is ground-biased, there's an excellent chance a ground gremlin is causing all three of your codes. If you want to verify it before tweaking the ground bolts, see this post about checking ground integrity:

topic628130.html

On a vehicle that old, it's probably a good idea to check the overall condition of the ground bus and the ECM grounds in particular.

Hey clamb. Try removing the sensor at the flywheel between the engine and the transmission and cleaning it up. Pieces of worn starter shavings tend to deposit on the sensor's magnet, which will throw off your reference readings. While you're down there, do the same with your crankshaft pulley sensor.

VStar and rgk, thanks for those excellent suggestions, I hope we can try them out tomorrow.

The grounds at the drivers side sensor were not looking great. We broke one bolt off in the head and had to drill it out, retap it. We chickened out on the other, but I guess we better look more closely.

I'll update you on any progress we make.

Thanks again
Chris

Don't go by sight, put a meter on it. I've seen plenty of instances where a whole bracket gets rusty and loses contact, and those bolts are on a bracket. The voltmeter won't lie to you.

VStar650CL wrote: ↑

Mon Dec 21, 2020 3:44 pm

Don't go by sight, put a meter on it. I've seen plenty of instances where a whole bracket gets rusty and loses contact, and those bolts are on a bracket. The voltmeter won't lie to you.

VStar,
Definitely using the voltmeter to check those connections, a new trick up my sleeve.
Yesterday we check pretty systematically and the connection post-clamp and to the bracket on the engine were both very solid and indicated only a few mV of drop.

Measuring at the ground points on the left side, it did look like we had readings from battery clamp to bolt @ sensor ground of up to 30mV. We had already twisted off one head and drilled out/rethreaded (1/4-28) one of them, so we went ahead and broke off the other and combined them on the new bolt. We thoroughly cleaned the ring terminals and reassembled. We measured about 6mV battery clamp to ring terminals at this point.

However, still throwing 1140&1145 pretty much immediately. We didn't see 340 right away, but it may have come back later. I measured ~3 0hms from the ground point to the ground wire on the connector, so that's a bit suspect, but there doesn't appear to be a great way to get to the wire to replace it.

The bolt on the passenger side connector came out with numerous aluminum threads still embedded, so today's project will be to try to tap that for some new threads if we can find the right combination in my collection of loose bolts. Once that's done, I'll look for the ECU grounds and see if there's anything we can address there.

Thanks for the help!
Chris

I didn't want to hijack your thread, but I am having a (maybe) similar issue. Please check out p0021-p1941-possible-short-to-ground-t628152.html.

rgk wrote: ↑

Wed Dec 23, 2020 2:14 pm

I didn't want to hijack your thread, but I am having a (maybe) similar issue. Please check out p0021-p1941-possible-short-to-ground-t628152.html.

Thanks RGK, I'll have to study the schematics more. I haven't worked on these Pathfinders too much, so I'm taking it slowly.