timing issues redtop sr20det

[zaneithan]

ok i tried searching but cant find this specific problem

so im stumped...hardcore, ive tried following the frsports walkthrough on setting the cas and everytime i stab it its a little skewed (not straight up), when trying to set the timing with the timing light, it acts really weird....the closer to TDC you try to set it, the worse the idle gets (eventually stalling) but if you go to the full extreme opposite direction (away from the second notch in from the left) it will idle better but still shakes like crazy, i dont know what it could be...

could it be the timing chain is off? because the two different colored timing chain links arent lined up with the notches on the cam sprockets but they seem to also be way too far apart to line up anyway (like 20 links apart).

the only thing ive ever done as far as messing with the head is put in rocker arm stoppers, which we torqued hand tight, not to spec (9lbs according to FSM)..im stumped, do i need a new timing chain? would not torqueing the cams to spec cause it not to want to go into timing? what could it be =\

i counted 20 links in between the two notches on the cam gears and the first set of lobes are pointing away from each other

[cotbu]

* " * * ' * TDC = " you want 15-+2 deg which = ' +-2 deg second mark from the right GL.

[jdmized240sx]

i had this same exact problem on my redtop sr. and so did my brother on his s13 black top. car would run shitty when set to stock. i finally got tired of trying to figure it out and brought it to carluch. dont know if you guys know him on these boards but when i get there. its doing the same exacty thing. tried checking for codes but none. so i finally just left the car with him and when i got it back he said he finally got it to read right, and the car ran great after that. never checked it with the timing gun after that but i sold my car so no more timing woes for me at this point.

[zaneithan]

not sure if this is related but i had to rewire up the TPS due to having an automatic sr wiring harness, could i have wired this wrong as well? (we only used 3 of the wires because thats all that was on the wiring harness)

[RedtopTech]

after you disconnect the tps per instructions, make sure that your idle is dead on. Sometimes it ends up being slightly higher or lower. Simply turn your idle screw to get it right about 850 rpm. Also make sure car is fully warmed up. Some people use the black wire on the rear of the engine as the timing light hook up but i prefer to remove the coil and use a spark plug wire between the coil and plug. Also dont use an electronic advance light. It doesnt work well. Just use a crappy old light from advance hardware.

[zaneithan]

so we set the timing mechanically to TDC (second notch in from the LEFT) and tried setting it electronically using a timing gun to (second notch in from the RIGHT as told), this is where it started acting really weird, it would not stay steady and would jump around a degree or two literally while watching it

it stutters at idle, idles really low, when you rev it up it seems to clear out (around 2k+ rpm id say)

the cam cap bolts were retorqued PROPERLY this time following FSM specs 1.4 first torque, 4.6 second torque and 8.7 for the final torque

we fiddled with the tps and it seems to be getting a signal (voltage, perhaps not proper voltage, not sure how to check this)

[zaneithan]

plugs are gapped to 32, and 2 of the coilpacks have cracks on the outside casing, not sure if that is effecting anything or not

[zaneithan]

anybody help please, im thinking that its either the cas is not working properly or something is wrong where the ecu is actually rapidly advancing and retarding the timing

[zaneithan]

so yesterday i ran diagnostic mode on the ECU and it came up with 55....no malfunctions

i ran a bottle of injector cleaner through the system and the car started spitting out all sorts of carbon build up and the idle seemed to calm down and wasnt so bad

3 of the coilpacks have cracks in them so i need to replace those, i took it for a drive and it started sputtering and backfiring and even though the idle has evened out a lot it has a misfire every now and then and when you rev it up, plugs could be fouled as well, need to check them

[drift donkey]

back firing could mean you have you timming to far advanced especial if the car feels like it has no power. Are the crank agnle senor mounting bolts postioned about in the center of there adjustment? Accourding to FSM they should be. Also if you are concered about the chain being off you can pull the valve cover and rotate the engine until the marks line up. It just might take you a minute. Pull the spark plugs it makes it easier.

[unicoladron]

are you locking the timing by unplugging the TPS to set the timing? that's how the aussies do it. check out this link:

http://plmsdevelopments.com/sr_setup...ign_timing_adj

[zaneithan]

we tried that and it didnt work, im going to try their suggestion of holding it at 1100 rpm

[Gjohnson7]

Originally Posted by zaneithan

3 of the coilpacks have cracks in them so i need to replace those, i took it for a drive and it started sputtering and backfiring and even though the idle has evened out a lot it has a misfire every now and then and when you rev it up, plugs could be fouled as well, need to check them

Have you replaced the coild packs yet??? I'm working on my first SR build now, so I'm not intimately fimiliar with the Sr timing. But on my old 94 Maxima, I had coilpacks and having cracks in the coil packs could cause major hesitation and stalling issues. I've always been told that if there are cracks in the coils, the spark can jump through the crack and never make it to the sparkplug, thus you are getting spark in your cylinders on every stroke.

[zaneithan]

just bought some actually, so im going to try that and some new plugs

[Chrischeezer]

the timing marks will never line up with the marks on the gears (it would take 100 rotations)

-remove the valve cover and make sure all the valves are closed on cylinder 1!
-put motor to TDC
-both cams should be facing outward and u should be able to slightly shake the rocker arms (indicating there is no cam pressure on it) both sides, intake & exhaust side on cyl 1
-at this point Then reinstall your CAS, make sure thoes dots go in perfectly.

[EATthis]

^ pretty much what he said... from enthalpy

http://www.rs-enthalpy.com/tuning/sr-cam-alignment.doc