Setting distributor timing without $$$$ scan tool? 1999 5.7 Suburban

[Schurkey]

1. Turning the distributor on a 5.7L Vortec DOES NOT CHANGE THE TIMING. The ECM reads the crank sensor to determine timing, not the cam sensor.

2. Turning the distributor on a 5.7L Vortec DOES change the rotor-to-distributor cap terminal alignment. If the alignment is too far "off", it encourages the spark to jump to the wrong terminal. It also increases the voltage required to jump the larger gap; which is hard on the ignition coil, and the insulation of the secondary side of the ignition system.

3. The ECM uses information provided by the cam position sensor to determine which of the eight cylinders is misfiring. If the crank sensor/cam sensor alignment is wrong, the computer could be blaming the wrong cylinder for a misfire.

But the big deal is #2.

If you don't bother to check the cam sensor to crank sensor synchronization, how do you know you have a problem until the coil or the secondary insulation fails? Just because it's not setting a code, doesn't mean it's optimum. You can stab the distributor a hundred times, and maybe the engine runs OK. Until you verify the cam offset, you've NOT done the job properly.

 

[97 bowtie]

I recently had to replace my crank sensor cuz my old one took a crap on me on the parkway at 70mph, the truck started rite back up and drove home and even drove to work the next day it had the Infomiss cam/crank correlation code. Before the sensor crapped out I had put an msd distributor in it and had to use the scanner to get the check engine lite off and the cam retard to 0deg.

after we put the new crank sensor in the check engine light would not stay off and kept throwing the same code, had to re set the cam retard again with the scanner to get it back in spec, it was running and compensating for about 35deg but the starter was grinding like a bit*h at times until I got the timing back in spec and it’s been perfect ever since

 

[Iknownothing]

So now I'm going to ressurect this post an prolly have nothing to add for anyone to learn from but , I have pulled my dist 3 or 4 times in the past day and yes I drilled holes out in the cap to watch the spark travel to the pin in the cap , that being said you can clearly see the spark in advanced or retard AT IDLE but at idle is not what your going to be causing at in over drive or in 1st 2nd or 3rd , now when I line up the mark on the harmonic balancer with the V notch to get tdc on the compression stroke , you can line up the rotor to point at the #1 pin on the cap and it will start and run and my cil even went off but I just drove it and now cruising at 50 -60 in OD ON a back road with the rpms around 1200 it's misfiring and almost a stumble , so the best way to do it if you don't have a scanner is to drill a hole in your cap by the #1 pin , point the rotor dead at the #1 pin start it up , and then you must rev your engine above 1000 rpms just like when using a scanner because on 99 an 2000 cam cam sensor coralation is want comes into play it may be timed at idle at 750 rpms but when into the gas that timing will advance or retard above 1000 rpms I found , and I can tell because I drive a 2000 c3500 with a utility bed loaded with tools an it weighs in around 11,800lbs and with the timing off even. +/- 2 I can tell cause it sputters when I need power going up a hill , and I even set it my sight through the hole above 1000 Rpms , but it stills needs to be set with scanner , but it is possible to get it to run. And to the untrained ear or someone not used to having the power that it should you may never notice , once I got mine set correctly I was amazed at the difference and the gas milage before I could literally drive around my neighborhood and watch my gas gauge drop prolly getting 6 or 7 mpg before maybe 12 or 13 now

 

[Iknownothing]

1. Turning the distributor on a 5.7L Vortec DOES NOT CHANGE THE TIMING. The ECM reads the crank sensor to determine timing, not the cam sensor.

2. Turning the distributor on a 5.7L Vortec DOES change the rotor-to-distributor cap terminal alignment. If the alignment is too far "off", it encourages the spark to jump to the wrong terminal. It also increases the voltage required to jump the larger gap; which is hard on the ignition coil, and the insulation of the secondary side of the ignition system.

3. The ECM uses information provided by the cam position sensor to determine which of the eight cylinders is misfiring. If the crank sensor/cam sensor alignment is wrong, the computer could be blaming the wrong cylinder for a misfire.

But the big deal is #2.

If you don't bother to check the cam sensor to crank sensor synchronization, how do you know you have a problem until the coil or the secondary insulation fails? Just because it's not setting a code, doesn't mean it's optimum. You can stab the distributor a hundred times, and maybe the engine runs OK. Until you verify the cam offset, you've NOT done the job properly.

So are you saying if you can get it close enough to run by pointing the rotor at the #1 pin on the cap and having the #1 cylinder at tdc cs that it will time itself ? Because before my CIL was on , I did exactly what I just explained and the CIL went off but now there's a misfire I can feel and hear when in OD at around 50mph and low rpms but the CIL has not came back on so I know it's out of time and it's chugging gas

 

[RedBurb]

I recently set the CAM Retard to 0 degrees on a L29 Vortec using a Snap on Solus (which I bought two weeks ago). Prior to that I had been driving blindly for a few months with the CR at -14 degrees without a code being thrown! Amazing. Therefore the engine will run by stabbing the distributor back in place and "eye ball" adjusting the rotor to the #1 Cylinder mark on the housing. That would explain why many folks here have gotten away with just eye balling it. However in my case there was a night and day difference in how smooth the engine ran and felt once the CR was properly set within the +-2 degree spec.

 

[454cid]

I recently set the CAM Retard to 0 degrees on a L29 Vortec using a Snap on Solus (which I bought two weeks ago). Prior to that I had been driving blindly for a few months with the CR at -14 degrees without a code being thrown! Amazing. Therefore the engine will run by stabbing the distributor back in place and "eye ball" adjusting the rotor to the #1 Cylinder mark on the housing. That would explain why many folks here have gotten away with just eye balling it. However in my case there was a night and day difference in how smooth the engine ran and felt once the CR was properly set within the +-2 degree spec.

The code doesn't get triggered until the low 20s, Ive read.