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Ignition timing

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XiKeiyaZI

15+ Year Contributor
6,967
55
Dec 28, 2008
Goldsboro, North_Carolina
I know this isn't as delicate as LINK or anything like that, but it's got my engine running poorly. It Sounds and feels decent, but I know that it doesn't have the power that it needs to.

I noticed that after I got my car up and running that it did run pretty good. I installed my MBC and related gauges and have been seeing boost between 10-15 PSI. At the moment, I have it turned down to around 10.

I can feel the car Miss. I can audibly hear it, but it isn't in a pattern, it's more of a stumble every now and again. New plugs/wires did not fix this. I then recalled, through all of the excitement of doing my first rebuild, that I didn't time the engine via a timing light and CAS.

I went to check the timing. It's WAAAY off, unless I'm not doing it correctly. On the Lower Timing cover, where the block is for the timing advance, it's at the top left, forward to the radiator. Well, my timing mark on my crank pully (inline with the timing mark used to make sure everything is in line when putting on the timing belt, is opposite of the timing block on the cover.

So say, the timing block is at 11 o'clock. My Timing mark on the pully is at 2 o'clock. No matter how much advance or retarding that I do with the CAS, it doesn't change.

Now I know there is a wire you have to ground, but I can't entirely be sure that I'm using the correct one. The harness in this car was pretty bad, but I was able to save it. Then again, I can't see this causing the timing to be off THAT bad, right?

This is a 90' GSX. I can't be 100% sure if it's a 90' engine. I just want to get this thing running as close to perfect as I can. =/ Any input would be lovely.

I also wanted to add that the old knock sensor in the engine was pretty burnt up and wired incorrectly. So I replaced it, and I BELIEVE I wired it correctly. One thing I've noticed is that every once in a while, my CEL will come on and I'll get a code in regards to the knock sensor every once in a while. I take it that the timing being off would cause this?
 
You need the timing adjustment connector which is located on the main wiring harness just behind the battery. There is only 1 prong on the plug. Ground that to the battery with a set of alligator clips. Also make sure you have your timing light connected to the spark plug wire on the #1 cylinder (the on closest to the timing belt).

I hope this helps!
 
You need the timing adjustment connector which is located on the main wiring harness just behind the battery. There is only 1 prong on the plug. Ground that to the battery with a set of alligator clips. Also make sure you have your timing light connected to the spark plug wire on the #1 cylinder (the on closest to the timing belt).

I hope this helps!

Do you happen to know what color that wire is? The plug...is unfortunantly missing. I also, sadly, have 2 other loose wires over there. -.-;;
 
You are welcome! Also you need to make sure that you are at normal operating temperature, your idle is set at 750 rpms, all accessories are off, and the transmission is in neutral.

Thankfully my Idle is perfect at 750-800.

I won't be able to try this until I get home today at 5:00pm, but....would grounding that one clip REALLY cause the location of the timing mark to be off THAT far?
 
No, this is not the fix. You should time it, but the engine will normally idle at 5* but when you gnd the connector it locks it a 5* so if the rpm changes it should stay right at 5*. There was another that had this issue and it turned out his pulley had spun where the rubber is in the middle.
 
pulley had spun where the rubber is in the middle.

To my knowledge that entire pulley is solid?....and is locked in place with a dowel pin from the crank?...
 
No, this is not the fix. You should time it, but the engine will normally idle at 5* but when you gnd the connector it locks it a 5* so if the rpm changes it should stay right at 5*. There was another that had this issue and it turned out his pulley had spun where the rubber is in the middle.

You are incorrect. When you ground the ignition timing adjustment connecter it takes the ECU control away so you can see the true timing. Then you advance or retard it with the CAS until you get it to 5* BTDC. Once you remove the ground from the connecter the ECU takes over control again. Grounding the ignition timing adjustment connector does NOT lock the timing to 5*. Keep in mind that we are talking about a 1g here.

To my knowledge that entire pulley is solid?....and is locked in place with a dowel pin from the crank?...

The crank pulley, aka harmonic balancer, does have a rubber damper in the middle of it. They have been known to fail, especially on engines with over 100,000 miles. I new factory one is about $100 and if you can’t get the timing set then it could very well be the problem.
 
just a quick question here im running a 1g nonturbo ------ seems if i set my ignition timing to 10 degrees i get better power?.......is this possible or am i imagining this should i go back to 5 degrees or really doesnt it matter ?.thanks
 
just a quick question here im running a 1g nonturbo ------ seems if i set my ignition timing to 10 degrees i get better power?.......is this possible or am i imagining this should i go back to 5 degrees or really doesnt it matter ?.thanks

Yes, you can gain power by adding timing, but 10* seems a little high. I'd back it down to 7 or 8* to stay on the safe side.
 
You are incorrect. When you ground the ignition timing adjustment connecter it takes the ECU control away so you can see the true timing. Then you advance or retard it with the CAS until you get it to 5* BTDC. Once you remove the ground from the connecter the ECU takes over control again. Grounding the ignition timing adjustment connector does NOT lock the timing to 5*. Keep in mind that we are talking about a 1g here.

Look at the timing map and tell me i'm incorrect. The timing is obviously not realisticly physically locked to 5* but as far as the ecu knows, it's locked at 5* so you can match it with a light.
 
I went home and took a look at the pulley. I DID notice the rubber ring, so I fess up and admit that I was wrong for assuming it was solid and humbly accept that it's seperately pieced together.

The one thing that doesn't make sense...

The center will ALWAYS be in the same location as the crank due to the dowel that comes out of the crank to help line up the pulley. I also freshly marked the timing notch position on the pulley, so no matter what, it should be the same. I also have another pulley from the 91' that I kept just in case, but it also looks like the positions are the same.

It doesn't make sense how if I JUST marked the position of the timing mark, that it would be off, period. ??
 
Look at the timing map and tell me i'm incorrect. The timing is obviously not realisticly physically locked to 5* but as far as the ecu knows, it's locked at 5* so you can match it with a light.

To clarify that a little...

Under normal conditions, the ECU constantly adjusts the timing (and ICS) at idle to maintain a steady RPM. It uses timing to instantly provide more or less torque as loads change, and you will normally see it fluctuating between 7-12 degrees or so, depending on what the mechanical base timing and the ECU's timing maps are set to.

When you ground the diagnostic connector, you are simply telling the ECU to not make any adjustments to the timing. So what you will see on the timing light in this case is whatever the timing is mechanically set at... which may be 5* BTDC or any other value.

So the proper way to set the timing is to take the ECU out of the loop, set the base (mechanical) timing to 5* BTDC, and then re-enable the ECU timing control so that it can adjust the timing (torque) as needed to maintain a steady idle.

*****

On the balancer issue.... if the rubber fails to the point that the outside can spin enough to throw the timing marks off that far, you probably would have noticed it by now if you've been running the car after discovering the timing issue. It probably would have completely grenaded on you and made a helluva noise. (Not that you shouldn't check it to be sure LOL.

If your timing is that far off and it's not something in the ECU causing it, I would start looking to see if your timing has jumped and make sure all the timing marks line up correctly.
 
Now, I drive the car. o.o Period. I check it daily for anything odd.

All timing marks are fine. Also... isn't the timing belt behind the pulley on the actual teeth of the crank pully? Not the Harmonic balancer >__> That would ONLY effect the AC and Alternator belts.... right? So even if the outside were to spin... it wouldn't damage the timing one bit. -_-a Or maybe I'm just not thinking of the exact thing you guys are talking about.

All I know are the facts -

1 : There is a small miss
2 : The CEL has come on twice now with a 200 Mile gap between each. Timing was retarded, so it was obviously knock.
3 : I CANNOT apparently get the timing correct? But I can get the car idling perfectly...
4 : Car was prevously pushing 14-15PSI. I turned down the MBC to 10ish. Car seems to enjoy that better. What it enjoys, I enjoy.

I know there is power missing. I just know it. I've missed something so obvious and I can't resolve it. I just don't have the hands-on experience to know what the hell to do. One of you guys needs to come here and show me how the hell it's done.
 
All timing marks are fine. Also... isn't the timing belt behind the pulley on the actual teeth of the crank pully?

Your last question there means that you aren't sure of the first statement. :)

Yes...the t-belt is behind the cover. By "all the marks aligned", what I mean is you need to pull the timing cover (total PITA the first time you do it), put the motor at TDC (top dead center), and check the timing marks that are cast onto the front cover and the cam gears to make sure the t-belt hasn't jumped.

Assuming we're not missing something and you are checking it correctly...

If the harmonic balancer has not spun and the mark on it is that far off from the timing marks on the cover, and the CAS can't be adjusted enough to bring it close with the ECU out of the loop... that means that the crank is out of position in relation to the cams (or CAS).

That would be a pretty big jump in timing based on what you described, and it seems unlikely that the car would run at all if it's that far off. (At the very least I think you would hear some valves clanking against the pistons LOL. But I would still pull the cover and see what's going on with all the timing components and make sure everything lines up as it should.

You could also have something flaky going on with the CAS...is there anyone around there that has one you could swap out? That would be way easier than pulling the cover, and you might get lucky.
 
Your last question there means that you aren't sure of the first statement. :)

You're absolutely correct. I am FAIRLY sure of what I said, but I wasn't 100% sure. I'm just leaving room for me to be corrected if I'm wrong.

I just did the timing belt this past weekend. Surely it couldn't have jumped timing? The car still runs damned good...I just know that the timing is pulled on it at the moment. I also tried to time it directly after I finished the t-belt and let the car warm up to Op-Temp.

I have a spare pulley, and THANKFULLY, a couple of spare CAS. Is installing a CAS simple enough? o.o Just wanna be sure before I go ripping things apart.

Note : If I rip off the Cover again, I'm drilling view holes and placing clear plastic over them so I can visually inspect the timing parks anytime.
 
Is installing a CAS simple enough?

Yep. Just be sure to align the mark on it correctly so that it's not 180* out. Here is a link with pics showing how it should be aligned:

RRE Instructions

Did you do the timing belt job or did a shop? Logic says that since this was just recently done and you are now seeing this issue....something didn't go back together quite right. :)
 
I did it.

I've done 2 before as well. The Only reason I did this one was because I threaded the wrong bolt into the oil pan and carved a nice groove in the last belt. =/

When I did it.. I made sure the Cam Gears were properly lined up. Dowel pins on top, timing marks lined up with the head via a straight edge. Made sure Oil Pump sprocket was in phase. Replaced Balance Shaft belt, timing mark lined up. Crank Lined up as well. Got the entire assembly back together and rotated 6 times. All timing marks lined up perfectly. What could I have forgotten?

I'll certainly be attempting a CAS swap when I get home.
 
the timing still could have jumped. i'd at least pull the crank pulley and line the tdc mark up on the crank sprocket and check the cam gears.
 
Ahhh...ok. One of your posts up there led me to believe you weren't familiar with the timing stuff. My bad.

Sounds like you covered the bases, and like I mentioned I don't really think it's a jumped time issue being that it is so far off, but it wouldn't hurt to check it again. Are you absolutely sure the outer balancer ring didn't spin? Normally it would just come completely apart, but I guess it could have just spun and then locked itself back up (temporarily).

I would definitely start with that and the CAS. If that outer balancer ring did spin, you want to replace it before driving the car. When they come apart at 5000 RPM's, it isn't pretty. :)

EDIT:

^^^ +1 on what ramsack said. It definitely wouldn't hurt to at least check the crank and cam marks, just to be sure.
 
the timing still could have jumped. i'd at least pull the crank pulley and line the tdc mark up on the crank sprocket and check the cam gears.

Likely gonna do that anyway. I tend to get nervous about things. -.-;;

I just looked at the CAS adjustment thing by RRE... I'm sorry but I don't see the difference between the pictures with one being 180* out and the one that is lined up properly other than Camera angle?

If that outer balancer ring did spin, you want to replace it before driving the car. When they come apart at 5000 RPM's, it isn't pretty

Oh.. God. xD Nice thought.

I'll remove the crank pulley and make sure that it's fine. I may go ahead and replace it with the spare that I have. I looked at it yesterday and it looked perfect, just a little dirty. I did notice, however, that on the one that's installed on my GSX, there are 4 circle indentions on the outer ring. On the OTHER pulley, there are only 2 and they are in a slightly different location.

Hrm..
 
I did notice, however, that on the one that's installed on my GSX, there are 4 circle indentions on the outer ring. On the OTHER pulley, there are only 2 and they are in a slightly different location.

Those are just machining marks from when they are individually balanced. They will all vary some.


I just looked at the CAS adjustment thing by RRE... I'm sorry but I don't see the difference between the pictures with one being 180* out and the one that is lined up properly other than Camera angle?

Click on them so they are full size, and look closely at the ends of the "tabs" that go into the cam. One side has a groove, and the other doesn't. That groove should be aligned with the small mark on the plate just below it.

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