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5.0 Timing Question- help appreciated!

Old 02-22-2016, 01:56 AM
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Default 5.0 Timing Question- help appreciated!

So I can't for the life of me figure out what's going on with my timing. I pull the spout connector, attempt to set it to 10*, but as I'm moving it to 10* it just sounds like it wants to die. It sounds like it's choking out and grasping for air. The more timing, the happier it is. How can this be? I'm not too familiar with the motor, I just know it's a 93 5.0 with gt40p heads and a gt40 intake. Maybe it's the cam? Maybe the timing chain? I'm stumped. I've done a good bit of googling but can't come up with it. Any ideas or help would be greatly appreciated!
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Old 02-22-2016, 08:45 AM
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Could be that your factory balancer has slipped & is now junk.
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Old 02-22-2016, 11:57 AM
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Originally Posted by tbone heller View Post
Could be that your factory balancer has slipped & is now junk.
I should've mentioned that I stuck a dowel in cylinder 1 until it was at TDC and the mark on the balancer was at 0. So I'm guessing it's lined up.. But it would by be the first time I was wrong.
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Old 02-22-2016, 04:16 PM
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Its normal for the idle to drop way down when pulling out the spout connector. Does it idle back up and run smooth after you plug the spout connector back in? If so, I wouldn't worry about it......

10 degrees base is really low though. I know 10 degrees is factory but I like to run more base than that......
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Old 02-22-2016, 04:25 PM
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Originally Posted by Five-o-joe View Post
Its normal for the idle to drop way down when pulling out the spout connector. Does it idle back up and run smooth after you plug the spout connector back in? If so, I wouldn't worry about it......

10 degrees base is really low though. I know 10 degrees is factory but I like to run more base than that......
Unfortunately I can't really even get it to 10 degrees because it wants to die.. Like really die not run good at all die. Lol it sounds terrible not like a low idle. Maybe I'll try and get a video. But its definitely not normal, I just don't know why... 😕
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Old 02-22-2016, 04:30 PM
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Balancer could be spun like tbone said. Is it a stock balancer? If so, how old?
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Old 02-22-2016, 05:15 PM
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Originally Posted by Five-o-joe View Post
Balancer could be spun like tbone said. Is it a stock balancer? If so, how old?
I don't know much about the motor, but I believe it's getting to be old and tired. But the marks at 0 when its at TDC on cyl 1. So that seems to mean it's not spun.. Or is there something I'm missing?
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Old 02-22-2016, 06:18 PM
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If to were me I'd put a new balancer on it, reset timing to TDC, and re-time it.

If you don't want to do that, then I'd keep bumping the timing up until it pings under wide open throttle, then back the timing down 2 degrees and just ride out like that.
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Old 02-22-2016, 08:56 PM
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This may be a totally dumb thing to say, however I was timing a Pontiac 400 a while back and by habit I put the timing light on the front passenger side spark plug (I'm a Ford guy). Same exact kind of issues you point out here. Of course, on the Pontiac 400 number one cylinder is on the driver side (I realized my mistake while on a beer break). Good Grief!

So make sure you have the timing light on number one! Passenger side front cylinder!
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Old 02-23-2016, 02:20 AM
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Originally Posted by V8MiataMike View Post
This may be a totally dumb thing to say, however I was timing a Pontiac 400 a while back and by habit I put the timing light on the front passenger side spark plug (I'm a Ford guy). Same exact kind of issues you point out here. Of course, on the Pontiac 400 number one cylinder is on the driver side (I realized my mistake while on a beer break). Good Grief!

So make sure you have the timing light on number one! Passenger side front cylinder!
I can totally see this happening and being super frustrated! However, in my case I'm confident the timing lights on plug #1, passenger side. I wish this were my problem!

I Think I may pull the balancer and timing belt, reset them with a new one, and try again. I just hate throwing parts at something without an official diagnosis. :/
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Old 02-23-2016, 08:56 AM
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I replaced tps, dizzy, plugs, wires, coil, and found I had plugged injectors. Still wouldn't go right, I had swapped 4 and 5 wires. Also discovered wobbly balancer. Symptoms were different though.
Good luck, you have my sympathy.

Last edited by Lateralgeez; 02-28-2016 at 09:24 AM.
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Old 02-23-2016, 10:26 AM
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Originally Posted by nnowa07 View Post
So I can't for the life of me figure out what's going on with my timing. I pull the spout connector, attempt to set it to 10*, but as I'm moving it to 10* it just sounds like it wants to die. It sounds like it's choking out and grasping for air. The more timing, the happier it is. How can this be? I'm not too familiar with the motor, I just know it's a 93 5.0 with gt40p heads and a gt40 intake. Maybe it's the cam? Maybe the timing chain? I'm stumped. I've done a good bit of googling but can't come up with it. Any ideas or help would be greatly appreciated!
Go back and check the basics: Plugs, wires, cap, rotor. Also checking for the proper firing order. It's often the simple stuff that gets us.

Originally Posted by Five-o-joe View Post
Its normal for the idle to drop way down when pulling out the spout connector. Does it idle back up and run smooth after you plug the spout connector back in? If so, I wouldn't worry about it......

10 degrees base is really low though. I know 10 degrees is factory but I like to run more base than that......
It should be at 10*. Once it's plugged in, the computer will take over and control the timing.
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Old 02-28-2016, 09:29 AM
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Hey now did you figure it out? Curiosity is killing me.
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Old 02-28-2016, 07:25 PM
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Originally Posted by Lateralgeez View Post
Hey now did you figure it out? Curiosity is killing me.
Unfortunately no :/ I'm replacing the TPS, but I'm not convinced it's going to fix it, but I know it needs to be replaced since one of the wires is barely hanging on. It wants crazy amounts of timing to run "right". Definitely open to more ideas..
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Old 02-29-2016, 09:42 AM
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Originally Posted by nnowa07 View Post
I should've mentioned that I stuck a dowel in cylinder 1 until it was at TDC and the mark on the balancer was at 0. So I'm guessing it's lined up.. But it would by be the first time I was wrong.
It is lined up when sitting still, but what about when it is running?
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Old 02-29-2016, 11:29 AM
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Originally Posted by tbone heller View Post
It is lined up when sitting still, but what about when it is running?
Is there an easy way to tell that I can't think of? I was just assuming if it's lined up when it's not running then it's lined up when it is. But maybe not.. ?
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Old 02-29-2016, 01:40 PM
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Originally Posted by nnowa07 View Post
I should've mentioned that I stuck a dowel in cylinder 1 until it was at TDC and the mark on the balancer was at 0. So I'm guessing it's lined up.. But it would by be the first time I was wrong.
I think I see your problem. This is not how you find TDC. You do need a piston stop. You can buy one, or make one out of a spark plug.

Screw in the piston stop, and then rotate the engine until the piston hits the stop, and you can't rotate the engine any more.

Make a mark on the balancer.

Turn the engine the other way until the the piston hits the stop again.

Mark the balancer again.

Exactly half way between these two marks is TDC for that piston.

It's more accurate with a degree wheel. But you can do it with masking tape, a pen, and a ruler.
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Old 02-29-2016, 04:14 PM
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Originally Posted by .boB View Post
I think I see your problem. This is not how you find TDC. You do need a piston stop. You can buy one, or make one out of a spark plug.

Screw in the piston stop, and then rotate the engine until the piston hits the stop, and you can't rotate the engine any more.

Make a mark on the balancer.

Turn the engine the other way until the the piston hits the stop again.

Mark the balancer again.

Exactly half way between these two marks is TDC for that piston.

It's more accurate with a degree wheel. But you can do it with masking tape, a pen, and a ruler.
I appreciate the help! That would certainly be a much better way of confirming TDC. However, I was able to feel the piston moving, and feel it stop moving, so I'm pretty confident in the TDC reading. It's at least close enough (+ or -1 or 2 degrees maybe?) to confirm that the marks are on point with the motor not turning. It read 0 when I could feel the piston at the top.
The motor wants to run at more like 20* ATDC, as opposed to 10*BTDC.

Thanks though, and the more brains on it the better. I'm just really hoping I don't have to pull it all and rebuild...
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Old 02-29-2016, 06:30 PM
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Yup, that's close enough.

Pull the valve cover and put a dial indicator on the #1 intake rocker arm. Using a degree wheel, make sure the valve events are happening pretty close to where you want them to. If not, then the cam could be installed wrong. Or it has the wrong firing order. There were a couple of different firing orders for Windsor cams.
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Old 02-29-2016, 09:00 PM
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Timing chain off by a tooth?
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Old 03-02-2016, 12:09 AM
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Just remembered something that might help! I had TDC on the exhaust stroke instead of the compression stroke. Stuck finger in spark plug hole and turned crank until pressure built up. Then used that TDC to set dizzy.

Now unless you've had the distributor out (I did) then the previous owner would have screwed up. Hopefully you have a way to contact them. Might be helpful. I learned some important things from both the builder and previous owner of my pos lol.
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