p01078

[crankor]

I'm starting to think this car is cursed... I got an evap code and a p0340 along with this p01078 then like 2 days later my driver's side axle fell off (Fortunately I was in my driveway when it happened).

As far as the code, I'm not exactly sure what it's from. The search is did says it could be from the cam sensor which the 340 shows a bad circuit in bank 1 sensor A. Im not sure if sensor A is the intake or exhaust cam. I replace the exhaust one recently with a Hitachi one but the intake i used a denso since I didn't have any other Hitachi ones... well I got another Hitachi and put it in the intake and swapped out the exhaust one for the denso that was in the intake one to see if the code goes away but I haven't had time to drive it since the axle broke.

I did get the new axle in but the bolts for it won't be here until later today. I did read that the 1078 could be related to the intake? But that source wasn't specific to infiniti. I also saw it potentially could be from a loose cam chain which I recently hope it's not that since I already took that all apart and it seemed fine so I didn't replace the cam tensioners or chains. OH I did find that the intake cam sensor connector clip broke so I wondered if it was just from that but I wasn't sure which sensor was A and which was B

[VStar650CL]

That's both sensors (intake cam P0340 and exhaust cam P1078) on bank1 (passenger side). Since they're next door neighbors at the back of the bank1 rocker cover, I'd be looking for something that affects both, e.g., a wiring issue at the back of the b1 head or a mechanical issue with the b1 rocker cover. It's possible a jumped sub-chain on bank1 could also cause it, you can verify that by streaming the b1/b2 intake angles and see if they match or if b1 is off. On VQ's a jumped sub-chain generally causes about 3~4 degrees per tooth.

[crankor]

Dang it, I replied to this and it didn't go through
Anyways, I checked the timings of b1 and b2 intake and exhaust cams and they appeared to be matching. I forget now which ones read what but I think the intake ones were both at 0 and the exhaust ones, the b2 was between 1 and 2, the b1 with the issue was between 3 and 4 but seemed to match when reving in neutral. I still haven't been able to drive it to see of the code will dissappear from the reader.

[VStar650CL]

As long as the intakes were both reading 0 at idle and the exhausts were approximately equal, your chains are fine. I guess it's possible (but extraordinarily coincidental) that both your b1 sensors are bad, but I think it's more likely you have a power or ground issue that's affecting both or some kind of issue with the rocker cover.

[crankor]

Not sure what i should be looking for.. I did switch out the valve covers to the aluminum ones so def coukd of neen some wonkiness along the way but maybe I should start with a voltmeter on the connectors?

[VStar650CL]

Yep, make sure they're each getting a solid 5V measured from the power to ground pins on the connector, then backprobe each ground pin with the engine running and make sure the drop (measured to the battery negative post) is less than 50mV (0.05V). You can also backprobe the data pins and compare the running voltage to the same sensor on the opposite bank, they should be identical or very close to it.

[crankor]

I checked the volts and both were 5.2 without the sensor plugged in and 4.8 with then plugged in on the b1 side. I did a trick I saw on YouTube with bringing a socket in front of the sensor with the power on and see the volts drop to almost 0 (0 2) then back to when moving it away. so here's something I found..... I went to check the intake valve timing on b1 but it only shows it for b2 on my scan tool.... shows both exhaust timing options. Not sure why that is. Also, there is no CEL for these but they are still showing up when I check for codes in general.

I did also notice tge cam teeth were kinda funky and not sure if that would play a part in this too? The oil isn't that old though..

[crankor]

Ok scratch the intake b1 not showing. I just loaded a different thingy and it was showing. They all look fine to me so im not sure why its still showing up as a code... would doing a timing relearn be beneficial to this?

[VStar650CL]

Ok scratch the intake b1 not showing. I just loaded a different thingy and it was showing. They all look fine to me so im not sure why its still showing up as a code... would doing a timing relearn be beneficial to this?

The relearn only affects the exhaust mag-draggers, but it couldn't hurt. If you're not getting a lit MIL it means one of two things, either the codes are "past" (the MIL was lit but isn't anymore because the condition cleared), or the codes are "first trip" (the ECM detected the malfunction once but is waiting for a second occurrence before turning on the MIL). In either case they should be erasable. The ECM also stores "permanent" PDTC's which can only be erased by the ECM passing an SRT (self-readiness test) for the system involved, which means not seeing the condition for a number of drive cycles under specific conditions. Many aftermarket scanners just don't handle that stuff clearly and correctly. So it's entirely possible your problem is gone and what you're fighting with now is a scanner issue.