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D-2.5-GT 09-15-2005 04:56 PM

HELP! P0021 Intake Camshaft Position Timing - Over Advanced
Anyone have any idea what this means?

See my thread of "Going to Kill the Dealer" as to what happened.

Opie 09-15-2005 07:13 PM



Two consecutive driving cycles with fault

Engine stalls.
Improper idling

1) Start the engine and let it idle.
2) Inspect the output of AVCS advance angle and oil flow control solenoid valve duty.

Is AVCS advance approximately 0 degrees, and the oil flow control solenoid valve duty output approx. 10%?

Check the following item and repair or replace if necessary.
Engine oil (amount, dirt)
Oil pipe (clog)
Oil flow control solenoid valve (clog or dirt of oil routing, setting of spring, clog of valve)
Intake camshaft (dirt, damage of camshaft)
Timing belt (matching of timing mark)

IF "NO":
A temporary malfunction. Perform the following, and clean the oil routing:
Replace the engine oil and idle the engine for 5 minutes, and then replace the oil filter and engine oil.

Legacy05 09-15-2005 07:21 PM

Hey Opie, could you tell me what they would do for a P2009?

Opie 09-15-2005 07:35 PM



Immediately at fault recognition

Wiring diagram:

Step 1:
1) Turn the ignition switch to OFF.
2) Disconnect the connector from tumble generator valve connector.
3) Measure the voltage between tumble generator valve actuator and chassis ground.

Connector & terminal
(E55) No. 1 (+) Chassis ground ( − ):
(E55) No. 2 (+) Chassis ground ( − ):

Is the voltage less than 5 V?

Replace the tumble generator valve actuator.

Repair the battery short circuit between ECM and tumble generator valve actuator.
Do you by chance have an up-pipe installed (not factory?)?

PhilT 04-29-2008 07:13 AM

Does anyone have the part # for the OCV, or has anyone changed one themselves ?

I'm getting the P0021 CEL with all the associated symptoms and need to get this done asap.

Opie ?

PhilT 04-29-2008 09:26 PM

It's amazingly easy to pull these out and check them, took me 10 minutes per side this evening.

Not a sign of any dirt on them, and they both moved very easily inside their sleeves, makes me think that there was nothing wrong with them.............except the car ran fine afterwards so who knows :confused:

Datalogging the VVT shows everything pretty normal, the maximum advance on both cams was 28 left and 26 right, anyone know what they have to get to, to trigger the CEL ?

amason 06-25-2008 05:51 PM

Hey PhilT,

Can you answer a few qq's for me?

- In what section of the vacation pics did you find the re/re instructions? I've come across a description of the system, and hoped to find them nearby, but so far no love
- I take it from the work you did that this sort of thing isn't covered by the powertrain warranty? (IMO that seems odd, as it seems to me to be pretty directly related to the engine!)
- Is there a sensor that could be faulty, or just the valve itself?

I'll post a quick data log of my VVT parameters in a bit...


PhilT 06-25-2008 08:12 PM

I pulled one out just to take some pics, as I forgot last time:

First pic shows the location of the port side OCV, the starboard one is exactly opposite.

To get it out, first pull off the blue plug, then slide off the hose marked, this doesn't have a clamp on so just pulls off.
Then remove the bolt with a 10mm socket.
The OCV then just slides out, you may need to prise it out as it's tight on the O ring.

This is what it looks like when it's out:

It doesn't come apart, the solenoid is clamped onto the valve. All I did was to operate the spool by hand to make sure it slides easily, clean up with WD40 if it's sticky.

Since I had both mine out, I have never had the CEL return, and no more stalling at idle.

I have the part numbers if you want to order new ones, I think they are around $160 each. What makes me laugh though, is that the dealer quoted me 2 hours labour to replace them :lol:

amason 06-27-2008 12:41 PM

Wow, thanks a bunch Phil, much more than I was expecting! Based on this, I think I'll start by looking at the left one...

(apologies for formatting)

Engine Speed (rpm) | Intake OCV Duty Left (%) | Intake OCV Duty Right (%) | Intake VVT Advance Angle Left (deg) | Intake VVT Advance Angle Right (deg)
811 9.41 9.41 0 0 (idle)
878 55.69 45.88 0 0 (throttle starts here)
1254 56.47 45.88 0 0
1770 57.25 46.67 0 0
2180 57.65 47.06 0 0
2526 57.65 47.06 0 1
2863 57.65 47.06 0 2
3114 57.65 47.06 0 4
3234 57.65 47.06 0 6
3062 57.65 47.06 0 8
2910 57.65 47.45 0 10
2682 57.65 45.88 0 13
2539 57.65 45.1 0 13
2351 57.65 44.31 0 14
2187 57.65 44.71 0 14
2016 57.65 43.92 0 15
1870 57.25 42.35 0 15
1718 57.25 38.04 0 13
1597 56.86 37.65 0 9
1466 55.69 39.22 0 6
1309 9.41 9.41 0 0 (throttle off)
1208 9.41 9.41 0 0

amason 07-16-2008 11:27 AM

After taking it out and finding the same thing (i.e. it seemed fine), and doing an oil change, things were better. Now they're worse again (with matching wonky data logs), so I think a replacement is in order, and could use those part #'s!


Andyjo 07-16-2008 09:25 PM

I've been having the same issue... well the came CEL, no trouble idling, or stalling, just the light.. so tonight i pulled out the drivers side OCV, it looked fine, so i nailed it w/ some WD40 and ploped it back in.. but the passenger side, i could not get out, there's a bracked that the OCV won't clear when sliding it out, did you have to remove anything else on the passenger side? I pulled out the airbox, and moved the coolant thing out of the way, but the bracket that the coolant box (has the same radiator style cap on it) screws onto is in the way.. I pulled a few other bolts out, but couldn't seem to get the bracket to budge, how'd you get around it?

PhilT 07-17-2008 09:50 AM


Originally Posted by amason (Post 1968559)
After taking it out and finding the same thing (i.e. it seemed fine), and doing an oil change, things were better. Now they're worse again (with matching wonky data logs), so I think a replacement is in order, and could use those part #'s!


The Part # for the OCV is 10921AA020

The right side OCV was a struggle to get it out past that bracket, but it did come, I think I loosened off the bracket first.

PhilT 07-19-2008 09:27 PM

I remembered how to get the right side one off now, I took out the bolt that secures the coolant tank, lifted it without removing the hoses, then bent the bracket slightly inwards.

This allows you to pull the OCV half way out, then turn it 90 degrees before pulling it the rest of the way out.

underpowerd 07-19-2008 10:11 PM

^lol, could have used that a few hours ago
...all i can say is it didn't take me 10 minutes :)

Andyjo 07-20-2008 03:40 PM

Ahhh... bend the bracket, that'll work.
Just blast it with WD40?

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