You should see a bunch of knock counts from starting it too.
Printable View
You should see a bunch of knock counts from starting it too.
i get zero knock counts all of the time. I will start by knocking on the engine and the sensor. If that does not work i will test the wire going to the sensor. I will ohm the sensor and i will check if its putting out an ac voltage when tapped.
I routinely get about 1000 knock counts shown in TunerPro just starting my engine.
Ya, it's not working right now.
so here is where i am at. I think their is a problem with the electronic spark control module. The module gets 12v with the key on. Their is a good ground from the module pin d to engine. Their is continuity between the module pin c and pin b7 on the ecm and their is continuity between the module pin e and the other end of the wire where it plugs into the knock sensor. The problem is is the escm is not giving out 5+ volts on pin e that goes to the knock sensor. Can i call that a bad escm?
Also when i take my dvom and check ohms between the center pin of the knock sensor and the body of the knock sensor the dvom shows a constant open.
That doesn't sound right.
I just want to verify that the blue wire coming out of the esc module going to the knock sensor is supposed to have at least 5 volts on it. Also i want to verify that i should get 100k ohms between the center pin of the clock sensor and the engine block.
The ESC gets a full 12 volts, I've never measured the wire going to the knock sensor to see what voltage it gets, however. Normally 100k is correct for the knock sensor, but there were a good number of knock sensors used and I believe that most manual transmission versions were 4k. If you're showing no resistance or infinite, it is definitely bad (assuming that your meter is working properly).
I have never measured the wire from an ESC to the knock sensor either so can't help you there. Considering the circuit, I wouldn't have expected that wire to have a voltage on it.
The knock sensor should measure 4k ohms or 100k ohms though. Offhand, I just don't know which one your EFI system should use.
Ok so i do need a new knock sensor and esc. I found this list of knock sensord and esc modules. ESC Module Knock Sensor Motor
----------------------------------------
16052391 ....10456287 ....5.0L V8
16052401 ....10456288 ....5.7L V8
16128261 ....10456288 ....5.7L V8
16065711 ....10456288 ....4.3L V6 and 5.7L V8
16128251 ....10456288 ....4.3L V6 and 5.7L V8
16131171 ....10456288 ....7.4L V8 I never saw one on a Big Block?
My current esc module is the 16052401. I found some new old stock modules on ebay. I was looking at a 16128251. Would that esc module work ok with the 7747 with a 5.7 v8. I know it says it will work i just want to be sure because it also mentions its for a 4.3. Also if i get a knock sensor at the junk yard i know to test it for 100k ohms but what ac voltage should i be getting out when i tap the block or the sensor? Thanks
I managed to score the metal bracket that bolts to the intake manifold that holds the map sensor and the esc module and the other vacuum thing with all three of those parts still attached for $17 shipped. Anyway i put in the new used esc module and i still dont have 5v going to the knock sensor. Can someone test their blue wire going to the knock sensor on a known good system and let me know if there is any voltage. Thanks
Can someone with a working knock system test their blue wire going to the knock sensor and let me know if it reads any voltage? Thanks
Just a few millivolts with key on engine off. Don't have a throttle body installed at the moment, so can't check engine on.
Thanks. I bought a new knock sensor off of amazon. It's supposed to arrive Saturday. I hope that's all I need to get my knock sensor circuit working.