Installing and correctly setting a vortec distributor

[MILLCMACK]

Hello all! Thanks for the help with this - this thread got me out a bind when my cap finally let go (looks like the last guy had a heck of a time getting the screws in and over torqued) anyways, I replaced the cap and rotor and was able to fire it right up, no CEL. Ran rougher than I’d like but not terrible. Did some adjustments by ear but didn’t want to risk not knowing for sure. Ordered a Obd2 cable from obdlink and dash command for my laptop (50$ for the cable 40$ For dash command), installed, plugged in and fired the truck up. Initial reading was -17* @ ~1200rpm. Doing it by myself I shut down, rotated a little and restarted and got -27*. Repeated going the opposite way (towards passenger side) and got the same -27*. Thought maybe i was being shy and did a little more and still -27*. Went back the other way to confirm and still -27* @1200rpm. Clearly doing something wrong here, any help/suggestions appreciated. Truck is obviously running slightly different in different positions (was really happy with the set after adjustments by ear honestly) but I’m not getting a good readout(?)

Edit: I do have some documents from previous owner where the shop he had it into said maybe the long crank when warm was distributor related. About 20k ago. Should I go ahead and replace the distributor? Can this be done without removing the plenum? After reading here and on gmtruck i am suspecting fuel pressure regulator due to the other symptoms I get

update- another user pointed out i was reading timing not offset. after a few failed attempts at getting it set via dash command using an OBDlink SX and veepeak ble, i was finally able to set it using dash command on the IOS app and a OBDLink MX+

 

[Mangonesailor]

Initial reading was -17* @ ~1200rpm. Doing it by myself I shut down, rotated a little and restarted and got -27*. Repeated going the opposite way (towards passenger side) and got the same -27*. Thought maybe i was being shy and did a little more and still -27*. Went back the other way to confirm and still -27* @1200rpm. Clearly doing something wrong here, any help/suggestions appreciated.

Glad to see you got it figured out.

See, for whatever reason if the computer sees that the cam retard offset is too far off, it'll limit your timing advance to 27*, period. I'm not sure why you saw "Negative"27*, but nevertheless it's good to hear that's done. Torque, for me, has always shown a positive number for timing advance (unless i'm on DFCO) as well as HP tuners (Again, unless i'm on DFCO)

Did you take any screenshots of what you saw on the scanner(s)?

 

[MILLCMACK]

Glad to see you got it figured out.

See, for whatever reason if the computer sees that the cam retard offset is too far off, it'll limit your timing advance to 27*, period. I'm not sure why you saw "Negative"27*, but nevertheless it's good to hear that's done. Torque, for me, has always shown a positive number for timing advance (unless i'm on DFCO) as well as HP tuners (Again, unless i'm on DFCO)

Did you take any screenshots of what you saw on the scanner(s)?

no its been a busy weekend and after finding a little coolant down by the oil fill tube i parked it and reached out to a few shops over the weekend to have the intake gaskets looked at. its ALMOST a job i could do comfortably but with warm temps coming i really dont have the time to take my time and learn anything new via mistakes as this is my primary backup for my other 3500.

i will report doug working for palmer ended up going the extra mile and got all of my packages re-licensed and working 100%

 

[Mangonesailor]

No sweat.

Redoing the intake gaskets properly and living a normal life takes a couple days, as I am one to let the RTV fully (24hrs) cure before putting coolant or pressure on it. Mine are seeping a bit of oil out the front (or maybe its a valve cover gasket tricking me) but I can live with it as I did it 7-ish years ago.

If you look around on here i'm sure I left some notes about doing the job. At the same time it's nice to be able to blame someone else if it's wrong.

When its being done HAVE THE OIL BAFFLE REMOVED AND INSPECT THE CAMSHAFT FOR WEAR.

Part numbers for intake gaskets, if you're interested:
Upper plenum: Felpro ms95787
Lower: Felpro ms95826

 

[MILLCMACK]

no its been a busy weekend and after finding a little coolant down by the oil fill tube i parked it and reached out to a few shops over the weekend to have the intake gaskets looked at. its ALMOST a job i could do comfortably but with warm temps coming i really dont have the time to take my time and learn anything new via mistakes as this is my prim

No sweat.

Redoing the intake gaskets properly and living a normal life takes a couple days, as I am one to let the RTV fully (24hrs) cure before putting coolant or pressure on it. Mine are seeping a bit of oil out the front (or maybe its a valve cover gasket tricking me) but I can live with it as I did it 7-ish years ago.

If you look around on here i'm sure I left some notes about doing the job. At the same time it's nice to be able to blame someone else if it's wrong.

When its being done HAVE THE OIL BAFFLE REMOVED AND INSPECT THE CAMSHAFT FOR WEAR.

Part numbers for intake gaskets, if you're interested:
Upper plenum: Felpro ms95787
Lower: Felpro ms95826

thanks! once we get the garage up this summer ill be a little more confident taking on this stuff. ill add that to the notes for them. i was going to wait and have it in at a performance shop next month but my soon to be wife's car is finally giving us grief so i got it in at a GM dealership my buddy has been working with for a few years now with his trucks. about an hour away but after talking with her there im comfortable and confident they arent shooting from the hip. i have on the list right now- gaskets (upper and lower), injector set, fuel pressure reg, Dist, wires, plugs and other relevant parts/seals. anything else i should add while they are in there?

 

[Mangonesailor]

thanks! once we get the garage up this summer ill be a little more confident taking on this stuff. ill add that to the notes for them. i was going to wait and have it in at a performance shop next month but my soon to be wife's car is finally giving us grief so i got it in at a GM dealership my buddy has been working with for a few years now with his trucks. about an hour away but after talking with her there im comfortable and confident they arent shooting from the hip. i have on the list right now- gaskets (upper and lower), injector set, fuel pressure reg, Dist, wires, plugs and other relevant parts/seals. anything else i should add while they are in there?

MAP sensor, replace the entire dizzy with a new metal unit from Auto-zone (It's a duralast gold, so dizzy caps and rotors for life), T-stat, what kind of injectors are you getting... bosch yellow-tops?

 

[Chevyman71892]

Hey fellow owners. I'm having a hell of a time with a timing issue as well on my 97 350 vortec Havent gotten around to messin with the distributor because it looks to be in the right position-but my cmp offset is running -66-70* no check engine light. Runs pretty decent still.. just don't like that it's so far off.. think it could be the distributor? It's a few month old accel. Any ideas guys. Thank you

 

[Mangonesailor]

Hey fellow owners. I'm having a hell of a time with a timing issue as well on my 97 350 vortec Havent gotten around to messin with the distributor because it looks to be in the right position-but my cmp offset is running -66-70* no check engine light. Runs pretty decent still.. just don't like that it's so far off.. think it could be the distributor? It's a few month old accel. Any ideas guys. Thank you

The dizzy body could seem right, but the rotor could be off a tooth. I would advance the rotor a tooth and recheck. If it increases the CMP then obviously retard it two teeth.

Either way, since you're able to see engine data take a look at your spark advance. Does it go any bit past 27* advanced? Mine would not if the CMP was too far off.

 

[vort97]

So I got the reader today, and downloaded DashCommand and Torque Pro. DashCommand isn't working at all for me, created an account, but I can't login or change my password. That's as far as I got with it.

Torque Pro worked. I manually added the PID for the CMP Offset and it seems to be working. I am trying to learn/understand the App a little more. I really like what if offers so far though.


I feel dumb asking, but can you walk me through how to set up the misfire stuff? You can PM me if that's easier. Disregard I figured it out

Hey there, newbie here and going through the many joys of haveing become a vortek owner... lol.. recently swapped dizzy also,, go the torque pro,and a dongle,, works, reads ecm and timing.. I also found 3 different versions of manually adding cmp but not getting any read with ether..did you need to add gm pid,s? and would you care to share the manual cmp program code?? I 've got the gauge on the screen,, just no go... I'm about to go out n find me a old ass carburated,timed, WITH points truck so I can just use a f,,,en screw driver n f,,,n timen light!!!!!!!!! n be done with... btw,, it should be close, but seems not enough. My hold down plate has some adjustment to it... also rememer driving my old duster slant 6 about million miles with no tune up,,, you guy ever change the cap, rotor on one of those??? pain in ass but still easier than this techno lucky charms secret spy ring b.s. gm came up with,,,,,, I've also heard that on some of the 97's that data was turned off for some reason,,coud I be the lucky lottery winner??? if youd rather pm or email,, let me know.,,, sorry bout the rant ya'll,,, but been deallen wth this fer months,,, luckily have a small truck to run(needs work also, ) so dont mess with the the ĉhev,, often , enogh maybe, but it needs to stop being yard art.

 

[SB71]

I wrote this article about setting a vortec distributor and thought it might be useful for y'all. I wrote it and coded the page on the tail end of a 14 hour graveyard shift, so let me know if you find something that needs correction, my brain starts to get fried at those hours.

http://www.gmtruckcentral.com/articles/distributor.html

The article won't pull up on my android phone any suggestions? Don't see any pictures in this thread either what am I missing?