One last shot... Breaking up!

BoostedSUV

Active member
Re: One last shot... Breaking up!

Well being as I changed the wires, plugs, dist cap, rotor, coil, coil pickup, and ign module I almost want to rule out igntion mechanics. I used the VOM and checked voltage at the coil, MSD box, and injectors while the truck breaks up and nothing crazy happens. Reads 13.8 to 14.2 depending on if fan is on or not. If I had a stock dizzy I would change it just to see but seeing as I changed the vital "organs" of the MSD one it would be hard for me to believe its the dizzy. Also when I scoped the dizzy with the timing light on each wire I did not get any spark drop out. Unless things are crossing up inside the cap and I can not see it. Its almost like the truck starts mixing up cylinders... I really need another pair of eyes, hands, and knowledge to help at this point. I'm lost :dunno:
 

WyoSyclone

Active member
Re: One last shot... Breaking up!

Well being as I changed the wires, plugs, dist cap, rotor, coil, coil pickup, and ign module I almost want to rule out igntion mechanics. I used the VOM and checked voltage at the coil, MSD box, and injectors while the truck breaks up and nothing crazy happens. Reads 13.8 to 14.2 depending on if fan is on or not. If I had a stock dizzy I would change it just to see but seeing as I changed the vital "organs" of the MSD one it would be hard for me to believe its the dizzy. Also when I scoped the dizzy with the timing light on each wire I did not get any spark drop out. Unless things are crossing up inside the cap and I can not see it. Its almost like the truck starts mixing up cylinders... I really need another pair of eyes, hands, and knowledge to help at this point. I'm lost :dunno:

Just a thought... I've seen a few threads talking about the metal contact at the end of the rotor not being wide enough to pick up the spark events/timing. When you take the cap and rotor off and look at the burn marks where are they in relation to the center of the contacts on the rotor and cap? Could it be that your timing is just far enough off that you're barely jumping the gap between the rotor and cap? Have you tried changing the timing a bit and seeing if that changes the breakup?
edit... did you put one of the composite gears on the MSD?
 

SloGN

9Sec Alky V6
Re: One last shot... Breaking up!

Well being as I changed the wires, plugs, dist cap, rotor, coil, coil pickup, and ign module I almost want to rule out igntion mechanics. I used the VOM and checked voltage at the coil, MSD box, and injectors while the truck breaks up and nothing crazy happens. Reads 13.8 to 14.2 depending on if fan is on or not. If I had a stock dizzy I would change it just to see but seeing as I changed the vital "organs" of the MSD one it would be hard for me to believe its the dizzy. Also when I scoped the dizzy with the timing light on each wire I did not get any spark drop out. Unless things are crossing up inside the cap and I can not see it. Its almost like the truck starts mixing up cylinders... I really need another pair of eyes, hands, and knowledge to help at this point. I'm lost :dunno:


could the phasing of the rotor to the spark lead in the cap be causing the issue? if there is toop much of a gap between the rotor button and the cap lead @ 0 degrees just thing how much it moves when the ecm calls for say 30* of timing.

It's very possible that the spark is actually arcing to the wrong/next adjacent cap lead.

There are so very good pics talking about this on here.

one way to find out is go buy a very cheap/ old dizzy cap and drill a large hole under the # 1 tower and then set the timing @ 0 degrees with the engine @ tdc and then you can see where the rotor button is at in relatenship to the #1 tower. could be a issue there.


http://www.syty.net/forums/showthread.php?t=67715&highlight=rotor+phasing
 
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BoostedSUV

Active member
Re: One last shot... Breaking up!

Rob I left the brass gear that the dizzy came with...

Rob and Pat, those are good thoughts and you are both thinking along the same lines. I put a new cap so I should be able to see the track marks clearly at this point. I will pull the cap off tomorrow night when I'm home and take a look. Jumping the spark across terminals would make some sense. I did not try to adjust the timing, just set it at zero and let the ECM control it. I guess I could back off the timing manually but I wouldn't know how to back the timing off using the .bin file. I think I have all the tools to do it but I just never messed with changing the tune.
 

SloGN

9Sec Alky V6
Re: One last shot... Breaking up!

not to ask a stupid question but you did double check that the wires in the correct order 165 432
 

BoostedSUV

Active member
Re: One last shot... Breaking up!

Yup, I have the chevy v8 and v6 firing orders memorized at this point. Lol
 

dgoodhue

BuSTeD 4.3
Re: One last shot... Breaking up!

This thread is so long to catch up on. Any chance of a summary, maybe start a new thread?
 

BoostedSUV

Active member
Re: One last shot... Breaking up!

This thread is so long to catch up on. Any chance of a summary, maybe start a new thread?

There is certainly a lot of reading on here. I wish I had the ability to go through and clean it all up so those who haven't followed can catch up. I wouldn't even really know how to sum it all up. Truck breaks up and shows going lean on O2 and WBo2 at very specific RPMs. Seemed to try and go over everything with out any luck.
 

dgoodhue

BuSTeD 4.3
Re: One last shot... Breaking up!

There is certainly a lot of reading on here. I wish I had the ability to go through and clean it all up so those who haven't followed can catch up. I wouldn't even really know how to sum it all up. Truck breaks up and shows going lean on O2 and WBo2 at very specific RPMs. Seemed to try and go over everything with out any luck.

You mention in the first post that Nolan Tuned around a similliar problem. Any chance you fixed the problem and the issue is 'tune band aid'.
 

BoostedSUV

Active member
Re: One last shot... Breaking up!

You mention in the first post that Nolan Tuned around a similliar problem. Any chance you fixed the problem and the issue is 'tune band aid'.

That idea has certainly come up. I have changed tunes all together with new injectors a few weeks ago and the issue still exists. I even tried running truck on the stock memcal with no luck.
 

jpalmer

New member
Re: One last shot... Breaking up!

man i wish you would find the problem. i can't even imagine how you feel. sorry bro.
 

BoostedSUV

Active member
Re: One last shot... Breaking up!

I took the dizy cap off tonight and I didn't see any track marks across the plastic like I have seen on a few caps but I did find what looks to be 2 spark contacts points on the terminals which could be normal? The cap was brand new and has only been on the truck while it's been breaking up. Let me know what you guys think??

SU1HMDAxNjAtMjAwOTExMDQtMTk1NS5qcGc.jpg

SU1HMDAxNjEtMjAwOTExMDQtMTk1Ni5qcGc.jpg

SU1HMDAxNjItMjAwOTExMDQtMTk1Ni5qcGc.jpg
 

SY2455

70's Veteran
Re: One last shot... Breaking up!

The buildup in your cap and rotor looked strange. Mine don't look like that after 15,000 miles and the current ones have 10,000 miles on them and look like new still. Are you sealing the cap with RTV ? The build up in the center of the cap and on your rotor may be part of the problem.
 

BoostedSUV

Active member
Re: One last shot... Breaking up!

The buildup in your cap and rotor looked strange. Mine don't look like that after 15,000 miles and the current ones have 10,000 miles on them and look like new still. Are you sealing the cap with RTV ? The build up in the center of the cap and on your rotor may be part of the problem.

I figure the build up is just from moisture from the truck sitting since june. I've put maybe 2 miles on it that since then trying to figure it out. I don't seal the cap with RTV....
 

SloGN

9Sec Alky V6
Re: One last shot... Breaking up!

I noticed that your msd dizzy has a accell ignition module in it. Have you tried another module?


The local advance auto,autozone can test them.

hell i have stocker that i replaced when i was having troubles with my sy. i swapped it out and it was not the problem but i kept it anyway. It turned out to be the pick-up coil bad so i just replaced the entire dist.
 

BoostedSUV

Active member
Re: One last shot... Breaking up!

I noticed that your msd dizzy has a accell ignition module in it. Have you tried another module?


The local advance auto,autozone can test them.

hell i have stocker that i replaced when i was having troubles with my sy. i swapped it out and it was not the problem but i kept it anyway. It turned out to be the pick-up coil bad so i just replaced the entire dist.

Thats the ign module I threw in there to replace the one that came with the MSD back when I was trying things... Changed that and the magnetic pickup.
 

WyoSyclone

Active member
Re: One last shot... Breaking up!

The dual traces (upper and lower) on the plug contacts look like your rotor wasn't fully seated down onto the dizzy at one point... the center contact of the cap looks like the center wiper of the rotor was actually rubbing against the cap.

Do you have another cap and rotor you could throw on real quick... if not, take and bend the center contact (if it's a raised flap type contact) on the rotor upward to make sure it has enough contact pressure against the cap... it definitely looks screwy.

Just looking again at the rotor... it looks really gunked up for just having a few miles on it.. I'd definitely put a new cap and rotor on it.

edit.... You can't take the dizzy shaft and pull it up and down can you?? Even the reluctor ring looks like it has operated at a high and low position. And what is the black crud under the pickup coil?
 

BoostedSUV

Active member
Re: One last shot... Breaking up!

The dual traces (upper and lower) on the plug contacts look like your rotor wasn't fully seated down onto the dizzy at one point... the center contact of the cap looks like the center wiper of the rotor was actually rubbing against the cap.

Do you have another cap and rotor you could throw on real quick... if not, take and bend the center contact (if it's a raised flap type contact) on the rotor upward to make sure it has enough contact pressure against the cap... it definitely looks screwy.

Just looking again at the rotor... it looks really gunked up for just having a few miles on it.. I'd definitely put a new cap and rotor on it.

edit.... You can't take the dizzy shaft and pull it up and down can you?? Even the reluctor ring looks like it has operated at a high and low position. And what is the black crud under the pickup coil?

The black "crud" is RTV from when I changed the magnetic pickup
 

SY2455

70's Veteran
Re: One last shot... Breaking up!

The reason I ask about the RTV was all the black that is pile around the pickup coil in your picture and it looks like the dist cap was tighten down on it at the edge.

A few questions for you.

1. When you changed the magnetic pickup coil, Did you check the gap between each of the timer core teeth ? I had 1 that varied as much as .045 on some of the teeth and as little as .005 gap on others.

2. When you change out the ign module, Did you use the die-electric grease on the bottom of the ign module ?

3. Did you test each of the wires and connections going to the dist ? You may have a loose connection.

4. All of the build up inside the dist is not good if it is from moisture. It has alot where it should be dry. With that much moisture you may have what is call the Corona Effect going on inside the dist cap.
 

BoostedSUV

Active member
Re: One last shot... Breaking up!

The reason I ask about the RTV was all the black that is pile around the pickup coil in your picture and it looks like the dist cap was tighten down on it at the edge.

A few questions for you.

1. When you changed the magnetic pickup coil, Did you check the gap between each of the timer core teeth ? I had 1 that varied as much as .045 on some of the teeth and as little as .005 gap on others.

2. When you change out the ign module, Did you use the die-electric grease on the bottom of the ign module ?

3. Did you test each of the wires and connections going to the dist ? You may have a loose connection.

4. All of the build up inside the dist is not good if it is from moisture. It has alot where it should be dry. With that much moisture you may have what is call the Corona Effect going on inside the dist cap.

Yes I used dielectric grease that was supplied with the ignition module and I also checked all the connections going to the dizzy and I couldn't find anything loose or broken. I'm going to check the gap of the magnetic pick up next and try moving the dizzy shaft up and down. I don't like the look of all the build up either but the cap/rotor are only a few months/few miles old. I changed tham after the problem started so I doubt they are causing the problem.
 
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