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dreaded p0340 cam sensor code, and an interesting observation

8K views 30 replies 9 participants last post by  Kooldino 
#1 · (Edited)
a new 2.2 with GSC S2 cams, and we have the exact same issue LVS had.
P0340
we replaced both cam sensors, no dice.
reset the ecu. no dice.
checked voltage across both sensors...perfect.


now here's something interesting.
the spirals, or lobes, on the cams themselves that trigger the sensor :


if you look at the far end of the cams. the "cutout" there.
We compared a few different cams.
on the OEM cams, they both face the same way.
On the Tomei cams, they face towards each other (like the kelfords do in this pic)
On the GSC cams, they face away from each other.

any engineering types wish to comment on this? Would this affect the way the sensor functions.
Coz we are baffled why this code is coming up, and we know the sensors are good as they were in a running motor just a week ago. plus we tried two brand new ones!.




^ here is the pic from the GSC website. sorry it's so small.
notice the cutouts face TOWARD each other in this pic. Just like the kelfords and Tomei ones.
in our cams - they face the opposite direction, outwards.
(and yes, we checked, we definitely have them in the right spots :) )
 
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#2 ·
PS i would really appreciate it if someone with these GSC cams working properly, had a chance to pop off their valve cover and take a look at the orientation for me!!

What i am wondering is - is this a manufacturing issue?
 
#4 ·
^ yeah i am sure there are 100+ sets running around in 4Bs by now.
Just struck us as odd.... exact same error LVS had. and pretty much identical builds.
I'll PM him. wonder if he's happy to pop the lid on his motor ;)
 
#6 · (Edited)
Thanks for posting this up Beeble, now I know I'm not the only one having this issue...Are you running the AMS 2.2L as well? I hope someone will have a solution for us soon.

On the side note my car is still down due to the fact we can't still get it to crank...all we did was unplugged the ECU and lost cranking....
 
#7 ·
Here are some pics when the lid was off:







Does it look similar to yours?
 
#8 ·
^^ interesting.... thanks for the pics.
LVS your cams are "faced inward" , just like in the manufacturer photos i posted.
ours face the opposite direction.

our 2.2 was not made by AMS but at the end of the day it shouldn't matter who built it. it either has to do with cams themselves or electronics AFAICT.

I'm becoming increasingly concerned that the wrong billets may have been used...
I'll contact GSC and see what they have to say about it.



it makes sense to me that they should both be facing the same way - as the OEM cams are - both cams rotate the same direction after all...
 
#9 ·
looks like they are out of phase to me...

Ads are YOUR cams the same as Daz's?
 
#10 ·
D , i can only comment on mine as the lid isn't on the motor yet.
Darrin's got the valve cover on. but i think Monday it will have to come off. I'm just assuming they are the same as both motors were built together.

i double checked mine - IN and EX are definitely in the right place. marks all line up on the head. but the cutouts both face outward and the OEM setup has one facing in and one facing out (ie both the same direction)

There's another head there with the Tomeis in it. the both face inward. and that motor ran fine...

so - possibly 180* out of phase? it's a remote possibility. the boys will have to triple check everything next week.

PS i thought it was only the INlet cam sensor that was detecting TDC for cranking? and i assume IN and Ex sensors are used in running to determine MivecActual?
does that sound fair?
as the code comes up in cranking, and it won't fire, i was guessing the inlet sensor was somehow the issue...
 
#11 ·
Any updates to your issue?
 
#12 ·
I think the shop is going to drop in a different set of cams that are known to work in another car (Tomei) ... if it fires up, well then we know what the issue is.
Should know in the next 12 hours, will update later today.

Mechanic is going to take detailed photos through the compression cycle with the GSCs and compare to the Tomeis on a motor that is on an engine stand.

Personally I'm convinced it's the lobe for the INlet cam sensor that is causing the issue. I think it's not triggering the sensor properly. well, not at all. The ecu is looking for that inlet cam to say it's at TDC with reference to the CAS signal as far as i know, and obviously that isn't happening and the ecu won't send spark while in that error condition. The MUT3 guide said that more than 2 cycles without a signal will trigger the code. I assume that means 2 crank revolutions.

We'll see...
 
#13 ·
By the way i should point out this is not my motor. it belongs to a mate of mine.
But my motor is the one on the engine stand, and is identical in every way.
So i have a vested interest in sorting it out!! :)
 
#14 · (Edited)
Cool keep me posted. If you guys find it is indeed the camshafts issue then I am pretty sure it is the same problem I'm having.

I noted your mate is going to put in Tomei for testing, but is he going go with them later?
 
#15 · (Edited)
I'm not sure re: the head/cams issue.
as in, I'm not a mechanic/engine builder/guru to know or give advice!
But hopefully someone else can chime in please :)


and no he doesn't want to run the Tomei cams long term.
it's a 2.2 with an AMS 900 kit. maybe AMS cams or Kelford Bs at a stretch.
But the GSC cams *should* work. many other people are running them with no issues. it's weird.
 
#16 ·
just a lile update :
GSC have been great with responsing to my questiosn from afar , i will send them detailed photos and their tech will look into it.

Sounds like LVS is getting new GSC cams to try out aswell, so we'll see what happens.
 
#19 ·
^Thanks for chiming in guys, I replied both of your PMs. Looks like this is getting to be a more common issue now.
 
#21 ·
Keeping my fingers crossed for you guys...and myself.
 
#22 ·
well its bad news all around really..

either the problem is what we think and its a PITA, or its not and we are still left wondering WTF...
 
#25 ·
Yeah lets talk there for now.
 
#26 ·
I doubt its the cams...I am running GSC s2's with a 2.2L and fully ported head and Supertech valves and springs. I haven't had any codes like this (one of the few codes I haven't managed to get).

This still baffles me. I wonder if its something AMS does to their head setup, you both have AMS heads right?
 
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