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Advancing my timing issues

6K views 22 replies 7 participants last post by  200sxOuTKasT 
#1 · (Edited)
Advanced my timing but noticed strange problems.

So I advanced my timing today, or at least tried to...I did as was instructed. I started by making sure I'm running high octane (92) gasoline. I let my car cool down while I played video games with my friends for a bit. After my car had cooled down, I went outside and turned the car on again and let it warm up to operating temperature with no accessories on at all. Five minutes later when the car is warm again I turn the car off, and go under the hood and unplug the TPS sensor. I turn the car on again and the car is just about to stall, but when I hit the gas it dies. So I turn the car again but as the needle starts to drop from the initial rev when starting the engine, I give it a little gas all the way to 3k on my tachometer and then let it idle again. The car again goes close to stalling but does. I then rev my engine up 3 times past 3k rpms to lock it in timining mode. I check my timing and it is on the 10 degree mark, the 4th mark from the left. I had a friend loosen my distributor and turn it to advance it 5 degrees to 15 degrees (the 5th mark). At that point I ask him to tighten the distributor again while I kept my eye on the engine's timing to make sure it doesn't move around. Once this is done I turn off the car, and replug the TPS sensor again and restart the car to go measure the timing to ensure its still at 15 degrees; and to my shock I realize I don't see the timing marks anymore. I decide to just unplug the TPS sensor right then to see whats going on. My idle again drops to the point of stalling and I check the timing to see that its at 15 degrees again. I don't quite understand why I can't see the timing marks when the TPS sensor is connected but I can see it when its not. And since I was going to PIR (Portland International Raceway) today, I decided that I would, just to be on the safe side, retarded my timing back to 10 degrees basically doing the same thing as before as when I was advancing it but retarding the timing instead. When I reconnect the TPS sensor and start the car, I can check my timing and again I had set it back correctly to 10 degrees and can clearly see it. What I don't understand is what I'm doing wrong? I listed out exactly what I did as detailed as I could to make sure that anyone reading this could tell me what step I skipped or what I could've possibly done wrong. Or should I not be able to see my timing when I reconnect the TPS sensor back on? I can't seem to figure it out. Thanks in advance for any help I receive.
 
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#3 ·
Sethticlees said:
Ok, maybe I should get this straight. I advanced my timing but don't know if it was done correctly cause of the results in the end. I followed AznVirus and 1997GA16DE both and received the same results both times. I couldn't see my timing marks after I plugged my TPS sensor back in and turned my car on after I had advanced my timing.
 
#4 ·
Same thing happened to one of my buddies cars. After we advanced the timming, we couldnt see the marks anymore. Unless we unplugged the tps, then the marks reappeared again. He said he could tell the difference, but we still were not sure if it was done correctly. I guess thats why I have never attempted to advance my timming. Can anyone else explain why this would happen?
 
#6 ·
200sxOuTKasT said:
I'm sortof suprised, plenty of people who advanced their timing on this forum yet not a single person experienced this?
this situation kinda happened to me , i say kinda because it was a symptom of a bigger prob. ..... In my case , after i did my jwt cam install i noticed some pinging so i checked the timing , and to my surprise the marks were on the opposite side of the mark , later on i found out my chain jumped a tooth... so that was a diff prob.

but after reading this post , i finally decided to try advancing my timing as well so i went through the procedure :: idle car , rev 2-3 times shut off. unplug TPS , restart , rev 2-3 times , check timing , adjust. I now just did this 5 mins ago :) and now my car is happily running at 15º with the marks in the right place !

while doing this i noticed one thing that could be the cause of the prob. ... Ill ask this question , not to insult anyone's intellegence :) .. did you who are having this prob with the marks , unplug the right sensor ? The TPS is the plug on the TB (throttlebody) the plug/sensor under the IAC valve. I remember b4 when i unplugged the IAC plug the car would not idle and would just die. When you unplug the TPS the car should idle normally.

i can provide pic if needed.

hope this helps some1

:D
 
#7 ·
is your timing gun functioning properly? and is the signal source coming off of the #1 wire? if you notice an abnormal rythem to the strobe of the light then that could be screwing with your mind.

my other guess is that when the tps sensor is plugged in the ecu may advance/retard (don't know which one it is specifically) your timing at idle. Try adjusting your idle speed before you adjust the timing.
 
#8 ·
I might've unplugged the wrong sensor especially if its suppose to idle normally still after unplugging it. My car has 3 plugs in that general area, two brown and one gray. From the driver side looking at my car the two brown plugs are closest and one is on top of the other. I thought the pictures I saw at the guides point at the lower brown plug, but am I wrong? Should I take a picture as well? Any pictures and such would be greatly appreciated.

And yeah my timing gun works, it works during every phase until the very last part when I plug back in what I think is the TPS sensor and check the marks only to find that theres nothing there at all. Also I can't seem to find this idle adjustment screw that has been mentioned before. There aren't any pictures of it and I'm just too dumb to see it myself. Could you possibly give me a detailed description of its location as well? Thanks.
 
#9 ·
Oh my god... I just reread 1997GA16DE's guide again, and it says its the top plug, and I unplugged the bottom one :dumbass: . Damn my dyslexia. So yeah, I'm going to have to wait till tomorrow to do it again because the timing light is at my friend's garage... Could anyone who's reading this please confirm that its the top brown plug? I have a 98, and according to 1997GA16DE's site, I have two brown plugs while most people have one?
 
#11 · (Edited)
James said:
your car won't always idle perfectly if you unplug the tps.... you have to make sure its in timing mode and that your idle speed is normal... if your IACV is clogged your idle may be low and stalls out when the TPS is unplugged.
yup thats what happened to mine .. my IACV was all clogged with some black crap, when i cleaned it out it now idles good when i unplug the TPS

ill take some pics of the plug and screw ... ill edit this post in a min :)
edit :: pics as promised
 
#12 ·
Wow thanks OmegaManEX, you're freaking awesome :thumbup: .

Oh and James, I noticed you have a 300zx fuel filter and radiator cap, does that help any? I've never heard of them as a performance modification before. Always thought fuel filter was more of a maintainence thing, which I need to have done soon, probably by fall or winter. If its actually better than I'd get one myself heh :) . And to clean the IACV, should I just take something like a toothbrush and scrub at it or is there a better way to do it?
 
#14 ·
Alright, sounds like work my lazy ass will put off till tomorrow when I try to advance my timing again perhaps, thanks a lot for your assistance James. If its not too much of an intrusion, may I ask if you'll take your car to the tracks as well? :) I'm really curious how the GA16DET's hold up in the quarter mile still :rolleyes: just can't help it.
 
#16 ·
James said:
Yeah I really want to... Just to skeered cuz I suck at driving the manual! hehehe but I will go... :thumbup:
i need to do that 5spd swap to ... someday ...
 
#17 ·
Wait wait, I'm being a dumbass again, the bottom connector is the TPS according to your picture? I'm so confused, 1997GA16DE's guide says the top one, AznVirus's guide points like in between, and your picture points at the bottom one, all have one less plug than I have. If you could please look at this picture, the plug with the blue arrow pointing at it is the one I should unplug no? And could anyone tell me what that plug the green arrow is pointing as is? and red arrow's plug? Sorry I'm wasting so much of your time.


 
#18 ·
you got one of those two plug newer TPS's... I don't remember if you unplug that one you have in that arrow or both... (I'm saying both that unknown plug and the one you have marked for the TPS are BOTH the TPS...) AznVirus (Deric) also has that same TPS. The red arrow is the IACV.

the idle adjustment screw is slightly to the left and up of the ???? green arrow... under that little black cap.
 
#19 ·
Wow, posting this picture did prove worth it now :thumbup: No one ever said exactly where that idle adjustment screw was, I thought it was more out in the open, now its under that cap, thanks again I've learned something new. Now for my TPS sensor still...geez...I dunno how to deal with this thing, that gray plugs a total ass to remove, I hope AznVirus sees this and decides to help a fellow brother out; or hopefully I can figure it out on my own.
 
#22 ·
se7enty7 said:
uh bump


which of the two is it? or both?
You unplug the blue and green one theese are both the TPS sensors! I finally figured out how to do mine and set it to 10
it was at 8. I'm running 91 with some sunoco 104 oxygenated race gas in the tank (like 5 gallons). How much advance is safe/optimal on a GA16DE anyone know? I think 12 should be my next setting. Anyway I'm datalogging it with the G-tech Prometer and a Car-chip EX so I should be able to figure it out soon enough. Ow-yeah the sensor up by the Idle adjustment screw (red arrow) should be left plugged in. It's only the screw you adjust. Be sure the engine has been thoroughly warmed up too. Have fun.

P.S. The timing marks disapear when the TPS is plugged in because the ECU adjusts the timing constantly and often times at idle the timing is unable to be viewed.
This is totally normal.
As long as your settings are correct in Timing mode you can tighten your distributor down, double check timing, turn off the engine, plug in the tps(S) yes, there are two on our cars because they were made in mexico. I dunno if thats a reasuring thought but it's still a good car.
 
#23 ·
Ah that was very clear and thorough, I hope I can do the same for you. I have heard of people going up to 19 degrees with 92 octane gas (I think Ninety-Nine-SEL was doing this on his old GXE), but people say 15 degrees is just enough for 91-92 octane gas and should be definently safe. My 98 GA16DE was set at 10 degrees stock when I was using 87 octane regular gas before. So your gas is definently overkill for 10 degrees, 15 degrees or more is definently possible, but most people just set it at 15 to be safe.
 
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