problems with timing

Has anyone had any codes thrown for timing issues. I do have a cam gear but when I first put it on I had no problems for about 3 months.

Well I just got my car back after 2 months 8days at the dealership (intake manifold). They worked on my car no questions asked about all the aftermarket parts I have. But when it came to the timing they blamed the gear.

Any ideas please and yes it is set at 0 degrees

one more thing when its not warmed up it runs perfect I guess because the advance or retard in timeing for emissions