Can timing be verified with a timing light
#11
p.s. both George and I are old school and old farts!
Here's some old school for ya! https://blazerforum.com/forum/street...rs-seat-94815/
Last edited by LesMyer; 09-09-2021 at 09:03 AM.
#12
Ok I purchased the bafx adapter from Amazon the one you suggested. I have installed it and finally figured out how to add the cpm gauge and rpm gauge. I'll check it today and see if I need to rotate the gear 180. I'll let you know how things worked out. Thanks for all the help ! You guys are amazing !
Last edited by jasondis; 09-11-2021 at 08:46 AM.
#13
Making gauges is the hard way to display a PID but you can do it that way. There is a different function under diagnostics menu that lets you choose and list multiple PIDs very easily. Either way use the CMP Retard PID that has the single asterik (*). No need to check if 6 lines up - that is only useful for initially installing distributor. If engine runs then CMP retard will do that for you much more accurately.
Go ahead and report CMP retard using the gauge. For your reference I'll post a step by step for displaying PIDs through the diagnostics menu later today. Right now we're going out to a brewpub for a few hours.
Go ahead and report CMP retard using the gauge. For your reference I'll post a step by step for displaying PIDs through the diagnostics menu later today. Right now we're going out to a brewpub for a few hours.
Last edited by LesMyer; 09-11-2021 at 11:11 AM.
#14
Here's the two PIDs displayed in the Diagnostic Function for my Blazer. I believe you have to Scan All and then save the PID list before this is activated. Then you can go in and select the ones you want to display.
Last edited by LesMyer; 09-11-2021 at 02:12 PM.
#15
Ok this is what I did today. I checked the CMP retard and is was -17. I pulled the distributor and lined up the crank on compression stoke and reinstall the distributor gear 180. The rotor is bang on pointing to the the arrow on the casting of the distributor. I rechecked the CMP retard and now I'm +10.5 . I then checked to see if there was any play in the timming chain. Everything looks ok with the timming chain. I'm don't know where to go from here other then modifying the distributor hold down.
Last edited by jasondis; 09-11-2021 at 05:28 PM.
#16
Just want to make sure you are using the CMPRET PID. Can you screen shot your gauge please? If so you will either need to modify or replace your hold down clamp with one that doesnt lock distributor in place. -17 degrees (or +10) is definitely enough to cause a misfire.
Last edited by LesMyer; 09-11-2021 at 05:06 PM.
#17
I'll give Les an assist to keep you going. We usually either replace the hold down with an adjustable one:
or elongate the hole in the OEM hold down to gain more adjustment range. You should be able to make up the rest of the spec with the hold down adjustment.
Edit: I see Les answered as I was typing. Carry on.
George
or elongate the hole in the OEM hold down to gain more adjustment range. You should be able to make up the rest of the spec with the hold down adjustment.
Edit: I see Les answered as I was typing. Carry on.
George
#20
If you want your misfire detection to work properly after changing (or even disturbing) a crankshaft sensor, you will very likely need to do a crank sensor relearn. I see it is on your list of replaced parts.
As a test, pull off each plug wire and see if it is detected as a steady misfire. IIRC Car Diagnostic Pro gets the positions of #1 and #2 cylinders mixed up (unless you use the alternate PIDs).
However please know that a crank sensor relearn does not affect how the vehicle runs - only how misfires are detected.
Do you feel any misfires with the current CMP retard setting? Anything different about the way that it runs?
As a test, pull off each plug wire and see if it is detected as a steady misfire. IIRC Car Diagnostic Pro gets the positions of #1 and #2 cylinders mixed up (unless you use the alternate PIDs).
However please know that a crank sensor relearn does not affect how the vehicle runs - only how misfires are detected.
Do you feel any misfires with the current CMP retard setting? Anything different about the way that it runs?
Last edited by LesMyer; 09-11-2021 at 07:15 PM.