CognizantPotato

I was getting spikes to around 0.7V when cranking. That’s pretty much all I tested on the new CPS.

I just tested and there is continuity between terminal A and the negative battery terminal

Yep. Just tested again with that procedure and it’s still reading low. I verified the multimeter is working correctly so it looks like it might be time for a new MAP sensor Thanks for the help

I did backprobe the MAP sensor. The highest I’m reading right now with the hose hooked and unhooked is 0.35V

Hi all! I recently bought an 89 Comanche with the 4.0. I drove it about 70 miles home. When I was roughly 3 miles away from the house, the truck started bucking and then just quit. After I got it home, I was able to start the truck by wiggling the CPS Connector. I looked at the pins in the connector housing and saw that one of them was melted or bent. I got a replacement CPS (I think the brand was BWD) and installed it... still no start. I’ve since then replaced the ICM because it looked like it had overheated at some point, but that didn’t help either. I just tested the MAP sensor with the key in the on position and got around 1.5V - 2V from the b terminal. From everything I’ve seen online the MAP sensor should be around 5V. I’ve also tested the new CPS and its spiking to around .7V when cranking. I’m wondering if anyone has any tips for me, or anything I can do to try to further diagnose the problem.