ack! timing issue after headgasket replacement?

[safarijeepjim]

ok folks here goes. just replaced my headgasket the other week, after putting it back together the timing was off a bit first try so the idle was rough. i gave it another go (well the guy helping was doing the timing) and the idle was spot on just like before i did the work so we put everything back together. well, now when i get hard on the throttle and boost it starts stumbling and missing pretty bad. so my question is, my car was tuned on dsm link and yes i do have quite a bit of upgrades.... does the tune have to be re-done after this or should everything be back the way it was before? i'm thinking of pulling it apart again come monday when i have a day off to do the timing myself! i'm tired of other people messin with my cars. does this issue i'm having sound like a timing problem? if i go through step by step with the timing and it still does this what should i be looking for? looking on link b4 at idle i was running about 14.6 a/f ratio..now its bumping around 12.5-13.5 if that tells you anything? i've never done timing before so i'm kind of a dummy when it comes to this and tuning. do i set the crank so the marks line up at tdc or btdc 5* for the tune? pretty sure the cam gears were lined up with top of the head using a straight edge...but like i said i'm going to check all the marks and see if its lined up correctly. help! i gotta get this beast running smooth and stong again!

 

[ChrisMgst]

If you have link you could post a log. v3configs [ECMTuning - wiki]
The car won't need to be re-tuned.
What else was done to the car? Perform a boost leak test.
This link should help with the timing belt job. http://www.dsmtuners.com/forums/art...5-timing-belt-tensioning-tips-4g63-turbo.html

 

[safarijeepjim]

Nice! Thanks bud. I do have link so ill look into posting a log tomorrow or so. Basically all I did was change the head gasket. I didn't have the timing tensioner tool so I'm wondering since the timing was done half assed maybe its not spot on. But anyways tomorrow is my day off so ill probably check my timing, plugs, and take it for a spin and I will run a data log. I haven't checked the a/f ratio when it starts missing, but I did notice at idle b4 it was running 14.6, 14.7. Now it's around 12.5-13.6 at idle. Ill have to search for testing for boost leaks but ill check that tomorrow too! Thanks for the response!

So I noticed today before I started tearing stuff apart that a hose popped off. It's the small hose at the end of the feul rail that plugs into a diafram and runs to a junction box deal on the fire wall. It came off at the diafram. Would that have been causing my problem? I have yet to take it on the highway and get on it hard cause I want to go over some more things on my car while its cooled off. Not really sure what that hose is for, or how long it has been off. I know it was hooked up when I put everything back together but I didn't put a zip tie on it like it had before. Would heavy boost have pushed that hose off?