To test the output of the cam sensor and get an accurate reading with a meter, you need to disconnect the coil wire, turn the key on, rotate the crank with a wrench and read the peak voltage. When running, the meter averages the signal since it is pulsed DC.
The scope will tell the tale. Be ready to see a lot of stray voltage.
The cam position sensor read well on the scope, stayed steady at 5v with good looking intervals inbetween when I went to scope the crank sensor I was putting my lead into the signal wire at the plug on the main harness side and the jeep stalled. I took the plug apart and found that the signal wire had horrible terminal tension so I adjusted that and put the plug back together, I did not have time to try and scope it again today so that's another project for tomorrows list. I took it for a drive and it stalled about 3 times in a 5 mile distance with the only difference being I could just turn key and it would restart and I did not have to get out and pull a fuse out. Gonna do some more testing tomorrow as time allows
No real new updates to report. Everything seemed normal in the scope sadly I am unable to print any data or save live screen because um using the bear system with software from the mid to late 90s and when I try to take a picture of the screen with my phone the picture comes out with black lines across the screen I ended up adjusting the terminal tension on the crmank position sensor plug with neither positive of negative results I took the jeep on a 150+ mile roundly trip Sunday and it stalled only one time on the highway at about 70mph and started back up in under two mins with no fuse removal needed. It stalled once on me this morning in traffic but I have noticed that I can almost catch it before it stalls. It spikes in rpms before it dies about a 500-1000 rpm spike and if I tap the gas I can catch it but it seems to have a two stall attempt to it, once I catch it and give it gas to stay alive I have about a 2-3 second grace period before it isles up and tries to stall again so long as I catch it both times with the gas pedal it continues to run fine and even if it did die without me catching it all I have to do is firm the key too off and to run again and it starts right back up I have not had time to do further diag with being so bust in the shop and the intense heat outside.
I love this write up and now, I'm now going to do the unforgivable, ask for advice, even though I've read and re-read the dirty dozen. The problem is so simple. 97/98 ZJ that loses it's settings, or so it appears.
Starts running like a dog, stalling every time you slow down, basically showing all the symptoms that I once would have ascribed to a blocked idle jet. Take the battery terminal off, leave for a few minutes, re-connect. Problem solved, for a few weeks.
Now, taking a battery terminal off is not hard. Every few weeks is not too big a deal, but now it's every few days and I can see where we are heading!
This is a RHD vehicle and the black boxes are out there in the open. All looks really solid and so far wiggling hasn't indicated anything. At first I looked at battery terminals and earthing points but I've worked through those. I'm wondering about a cracked solder joint somewhere in the brain but tracking that down is an escalation of the campaign so I'm asking for help from anyone who's had a similar problem and nailed it?!
I think they call it ADHD, Zeejay. We have meds for that, but a well placed thump on the noggin' usually works. ( I know, because I've deserved quite a few in my lifetime...usually administered by an old Master Chief)
Back to the stalling issues....
Here's another one for the endless list of possibles:
Since the PCM gathers data from the TPS, Crank Sensor, Cam sensor and Coolant sensor at start up and then adds the upstream o2 sensor at warm up, it's critical that all those connections be secure. That's a given.
I found a new one today. The black/light blue wire on my TPS connector is funky. It's also the Ground ( through the PCM) for ALL of the above mentioned sensors. I isolated the single wire by removing the outer sheath and wiggled it up close to the TPS while the engine was idling. Guess what ? The idle picked up as if I had pressed the gas pedal. I think Rockauto sells those connector ends and if not, I'll snatch one from a junk yard. One more problem down....100's to go.