4.3L Vortec Getting a Rebuild
#241
If this checks out, I suspect the outer ring on your balancer has slipped a bit. It happens
If this is the case I would then pull the distributor out and reinstall with the rotor turned 1 tooth clockwise to compensate for some slippage of the balancer ring. (If ring slips and you use marks to install distributor, distributor gets installed in a rotor-retarded position)
If this is the case I would then pull the distributor out and reinstall with the rotor turned 1 tooth clockwise to compensate for some slippage of the balancer ring. (If ring slips and you use marks to install distributor, distributor gets installed in a rotor-retarded position)
Last edited by LesMyer; 05-15-2022 at 05:00 PM.
#242
Another check is to pull the coil wire and see if you are getting a nice steady spark out of the coil while cranking. This should functionally check the crank sensor mounting in your new front cover.
#243
Thanks Les, been raining all day today but I got out there and checked to make sure the distributor is in correctly. I felt the puff of air come out the spark plug hole right as the distributor was coming back around to the 6. It seems to be as close as it will get to the 6 while the marks are lined up on the balancer as well so I’m not sure here now… Should I try moving it one tooth up? I will see about checking the coil later today.
#244
If it actually will run on its own (even a little), check cam sensor retard. IIRC you have a capable scanner, right? Also check for codes, even pending codes can give us a clue. Or you can punt and move the distributor rotor 1 tooth clockwise from its current position and see what difference that makes.
Last edited by LesMyer; 05-15-2022 at 09:51 PM.
#245
Thanks Les, I, unfortunately, don't have a scanner to read cam retard. I was wondering if you know if Dash Command supports reading that on the iPhone version? My scanner reads spark advance but I don't think that will be much help to me here. Now I've done a fair bit of research about this, mainly about all the smoke coming from the intake, and keep ending back up at the same conclusion that it must be my ignition timing is off? I haven't tried testing my ignition coil yet, I don't really know how to is the problem. I'm thinking I can just plug the coil wire into a spark plug, but then how could I easily ground the spark plug out? When I get home from work later I will give everything another look through and see about moving the distributor one tooth clockwise.
#246
I agree. Distributor not in right is almost certainly the culprit.
Dash Command iphone supports cam sensor retard if you have purchased the enhanced GM PIDs for your vehicle (from within the app). Extra $10 per vehicle.
Do me a favor and grab hold of the balancer outer ring and see if it can be turned on the center (with some effort). They are rubber mounted and the rubber degrades.
Remember that on your vehicle the timing of the ignition coil firing is determined only by the crank sensor and PCM. On your vehicle the distributor only gives the spark a path to the correct spark plug. If the rotor isn't pointing at the correct terminal, its not going to run (even if spark is delivered at the correct time). This is a pretty unusual setup for modern fuel injection, but was done so multiple coils were not required.
If you want a different check on your crank sensor, just see if your current scanner will read RPM when engine is cranking. That will do the same check on crank sensor as the ignition coil test.
Dash Command iphone supports cam sensor retard if you have purchased the enhanced GM PIDs for your vehicle (from within the app). Extra $10 per vehicle.
Do me a favor and grab hold of the balancer outer ring and see if it can be turned on the center (with some effort). They are rubber mounted and the rubber degrades.
Remember that on your vehicle the timing of the ignition coil firing is determined only by the crank sensor and PCM. On your vehicle the distributor only gives the spark a path to the correct spark plug. If the rotor isn't pointing at the correct terminal, its not going to run (even if spark is delivered at the correct time). This is a pretty unusual setup for modern fuel injection, but was done so multiple coils were not required.
If you want a different check on your crank sensor, just see if your current scanner will read RPM when engine is cranking. That will do the same check on crank sensor as the ignition coil test.
Last edited by LesMyer; 05-16-2022 at 06:10 PM.
#247
Thanks Les, I'm going to look into getting Dash Command here, I'll need a Bluetooth adapter too, unfortunately. I forgot to say in my last post but it didn't pop any codes when I started it. Les, this whole time I thought you meant the balancer moved a bit when I was putting in the distributor, like the engine just rotated a bit, not that the marks on it slipped out of position! This would make more sense being that all the marks seem to be lined up right now and it still doesn't run well, I will check this now and let you know. My scanner now definitely reads RPM so I will crank it a bit more and make sure it will read properly.
#248
Les, checked balancer by trying to turn it and it wouldn’t budge. However I have found something here. Scan tool hooked up looking at RPM while cranking and it showed a steady 0. Hmmm, I really thought the tach on the dash was working when I started it but I guess not! Now I’m just wondering how it even ran for a few seconds then if my crank sensor is not working at all?
#249
Les, checked balancer by trying to turn it and it wouldn’t budge. However I have found something here. Scan tool hooked up looking at RPM while cranking and it showed a steady 0. Hmmm, I really thought the tach on the dash was working when I started it but I guess not! Now I’m just wondering how it even ran for a few seconds then if my crank sensor is not working at all?
#250
I just checked and my bluetooth scanner showed 150 rpm when cranking on my 2001 Blazer. Please see if yours is putting out any spark and if so is it steady?
Last edited by LesMyer; 05-16-2022 at 09:23 PM.