Timing keeps changing?

[RS12Turbo]

So I've had my ca for almost 2 years now. When I first installed it, I set the timing to 15 degrees (2nd tick mark from the right). Ran great no probs for several months....then one day it started missing under wot in upper gears. Checked the timing and it was between the 10 degree and 15 degree mark I re-set back to 15-17 degrees, and it was back to strong pulls with my wot miss gone. About 6 months later, same thing....started missing at wot in the upper gears. Checked the timing, and it was back down between the 10 and 15 degree marks. Re adjusted it back to 15-17 degrees, and back to running normal. About a week ago, I got the miss again at wot.....checked the timing today, and it was down closer to 10 degrees . I re-adjusted it back to 15-17 degrees...haven't test drove it yet, but if history repeats itself...the miss should be gone(I'll drive it here in a few hrs).This can't be normal....anyone else have this problem? Is there something that needs replacing or something?

[progman]

If you CAS has to keep going further and further in one direction it will eventually get so you can't time it anymore. If this is the case your CAS is dieing. I had one that died. Other wise, are you tightening the CAS after you set your timing?? :P

Other than that I don't know what could be doing that.

Is your CAS about int he middle of the adjustment range when the timing is right?

[RS12Turbo]

Hmmmm, no the cas is rotated closer to the advanced side than in the middle....each time I have to re-adjust it, it gets closer to the end. Not there yet though.So it sounds like my cas is crapping out slowly? Yes, the 3 bolts are tightened down .What other cas will work? Pulsar ca18de? http://www.partsamerica.com/Pr...Set=A

[bentvalves]

take your CAS out and have a close look at the half moon and splines in the end of the cam with a flashlight, use a pick or Q-tip to clean the grease so your able to have a close look. Are you running a modified upper cover by any chance?

[RS12Turbo]

take your CAS out and have a close look at the half moon and splines in the end of the cam with a flashlight, use a pick or Q-tip to clean the grease so your able to have a close look. Are you running a modified upper cover by any chance?

No...just the unmodified stock cover.........on the splines, what am I looking for?

[IggyEGuana]

Belt skip possible? Would prob have more low power/miss problems but u never kno

[rico05]

How are your tensioners?

[bentvalves]

your looking for worn splines around the half moon.

[RS12Turbo]

I'll have to pull the cover off and check the tensioners/ belt. Could it be a slipped belt? Engine idles perfectly smoothe....and the miss at wot was gone with last nights test drive as suspected

[progman]

I vote for dieing CAS. You should be able to notice if your belt flipped a notch and it wouldn't keep getting worse like that. You can use a ca18de CAS. but good luck finding one (they are like $300+). You best bet is to get someone on the forum here to sell you a used one. Pull off you timing cover and count the cogs to check the timing just in case.

[dash]

try rocking the crank pulley to see if it has any play. Keyway could be wornthe motor I got like that had worn the crank timing cog key also

[articzap]

JDM CA18DET correct timing is 10 degrees FYI.

Is the CAS keep moving back to the same spot or is it almost maxed out?

[RS12Turbo]

JDM CA18DET correct timing is 10 degrees FYI.

Is the CAS keep moving back to the same spot or is it almost maxed out?

It's close to being maxed out.....little bit of adjustment left.You sure about the 10 degrees? I'll have to check the fsm again.....I thought I remember seeing 15 degrees?? Says that here anyways......zerothread?id=114954

[dattodude]

Once the engine is warm, disconnect the temperature sensor (red one) while checking the timing. If the engine timing starts to behave, replace the sensor.

I've heard stories of faulty temperature sensors causing timing issues.

This is 'second hand information', but it's easy and free to check.