redbird_400

Dealership wants over 100 for it so I figured I'll just get one from a junkyard. If anyone could help me find a pic or tell me where it is located that would be cool. Only got a few hours left to find out so if you know real quick please post.

thanx

Trickster

Are you sure you've got the right terminology here? The knock sensor is located in the engine block on the passenger side just in front of the starter. It only costs about $12.00 + tax. Maybe you are talking about the Electronic Spark Control (ESC) module. It is located on the driver side firewall behind the fuel pump relay, MAF sensor power relay, and MAF burn-off relay. Still should not be $100.00, I think mine only cost $48.00 + tax.

redbird_400

The wording maybe wrong, these are the words from the dealership. "I found code 43 -knock sensor module circuit- I tested and found the knock sensor module was not seeing a trigger all the time and the knock sensor had high resistance."

This is from http://www.thirdgenresource.com/tpi_facts

"The electronic spark control components provide maximum advance, if engine knock is detected the spark is automatically retarded."

In the link above and from some other research on forums here, this error code comes in tie when the temp of the engine rises and the knock sensor sends the ECM a signal indicating a knock or just some kind of irregular voltage.

Things that I have tried to do
>swap out the ECM with another that I had laying around, came from either the original 89 bird or a camaro of the same year. Same engine.
>change the oxegen sensor
>unplug the knock sensor and drive the car to see that the error came up under the same condition
>swaped out the ESC Module with another that was from the 89 Camaro

Things I should do
>follow the wire from the knock sensor and make sure its not near any spark plug wires or any other wires that would put out highvoltage.

redbird_400

k, I've got the dirrections to about 10 different boneyards, all pretty much on the same street. There so many 3rd gens out there its just... crazy.

SO all I need is to know where all these moduls are. I'm just going to buy a load of them and throw them on. They are pretty cheap from the junkyard.

Things where I know where they are
>Knock sensor (bottom block, pass side)
>ESC module (driver side, flat black module behind a couple others)
>oxegen sensor (haha.. that was almost worthless to type)

Things that I have no clue about
>Knock sensor control module (honestly never herd of it)
>Anything other module that would affect and adjust the cars timing. Modules and sensors that would have to do with spark control.

-----------------edit/add----------------------------------------
This link may help.

http://www.thirdgenresource.com/sens...ays__etc__?b=1

Few things that I have replace I see on there such as the ECS, TPS, and oxegen sensor. Are these the only sensors that may be causing this issue? I'm going to try to replace the ESC and the knock sensor, also reroute the wire away from other wires to see if this will solve the problem. Please, with any info reply if you know something more or think you might and are not sure, reply anyway. All tips are welcome.

Trickster

Here is a troubleshooting chart for you to look at. Another board member who was having a similar problem found a broken wire going from the ESC to the ECM was his problem. The wire goes through the firewall on the passenger side to the ECM. BTW, there is no knock sensor control module on our cars. You will notice in this chart that I am sending you, that the knock sensor is tied into the ESC. That is the control module they are talking about, just bad terminology on their part.

Trickster

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redbird_400

wow... that was extreamly helpful. Thanx dude, though it still may only be the way the wiring is routed I'm going to go ahead and pick up another ESC and new Knock sensor. Replacing these two and rewireing should fix it up. I'll post later today what happens. Thanx for all the help and those two pages, wish I could print them out, need a printer. Well off to the Junkyard, Thanx again!

redbird_400

k well.. I put in the ESC module that in that I got from the junk yard. Has the same numbers on it as the current one in my car. Bought a new knock sensor from pep boys. Coulnt get the old knock sensor off so I ended up rerouting the knock sensor wire away from every wire possible under the hood. Since I coulnt get the old knock sensor out lol I just put the new one on the end of the wire, surrounded it in blue paper towles an stuffed it in a corner for now. I'm not sure if it needs some kind of vibration but how it sits now, just for testing, its getting no vibration at all but is hooked up. Drove the car for about 15 miles before the error code 43 came up again. Tomorrow I'm going to track down these two wires that go to nothing near the ecm. There is a grey one and a black one I belive, mgiht have something to do with it. Enoguh for me tonight, I'll post updates tomorrow and if you have any helpfull tips, please let me know.

eric305TPI

If the sensor isn't mounted in the block then it will not register knock when the ecm performs the knock test.

redbird_400

I'll try to pop it on today after work. Havnt had to much time latly. But the sensor has to read some kinda vibration you say? I was under the impression that it just had to have a 12v current and that would drop lower if it read a knock, then send the signal to the ecs, I'm not sure though.

RB83L69

From the ESC module's point of view:

knock sensor wrapped in paper towel with body not grounded = disconnected, even if the wire is plugged in

That's why you're getting the code. AFAIK the ECM doesn't do a "test" of actual knocking; i.e. advance the timing until it hears knock or whatever.

redbird_400

k so here is the latest. I tried to follow the wires from the ESC to see if they were either grounded out or drawling current from another wire. Coulnt really see so I cliped two wires from the ESC, the ground wire (brown) and the white wire (goes to knock sensor) I wired the knock sensor to the ESC with my own wire that is less then a foot long. Grounded the ESC ground wire to a ground point over there near the ESC itself. Messing around with these wires and the other two from the esc (pink wire 8 Volts, and black wire 12 Volts) On random starts the check engine light would come on. Sometimes after the 5 seconds sometimes after much longer. Everytime I would test the voltage to the Pink wire the check engine light would come on, and possibly for the black wire also. Both with error code 43. I started to follow the pink wire to see if it was possibly grounding out somewhere but didnt see much after pulling on it a bit to see where it was going. The last time I started the engine the check engine light didnt come on, reved it up quite a bit, started taping on the knock sensor which was just laying there and no error code. Drove it around romping on it quite a bit which before would for sure pop up that error code, the code didnt come up. Stopped at the cornerstore shut off the engine, started up drove around more with heavy acceleration, still no error code and no timing readjustment. Maybe there the black or pink wire was grounding out somewhere? But this doesnt prove anything yet, I'll have to drive the car for long distances before I really know if this has solved it, if not I'll probably clip the black and pink wire and just rerun new wires to the ECM. Its just to hard to find shorts in those wires that go behind the engine and through the firewall.


So the Knock sensor should be grounded? the metal sensor itself? ok well I'll ground it if that code pops up again. Do you think the readings below are corect?

Voltage test while idle at the ESC
Pink wire= 12V (ignition)
Black wire= 8V (Spark retard signal wire)
Brown wire= 0V (Ground)
White wire= =V (Knock sensor)
>With the check engine light on or off the voltage stayed the same

redbird_400

k, I solved it over this week end.

Parts used,

650 Holly carb
Aluminum GM intake manifold
Accel distributor with coil ontop
Fuel pressure regulator
some wire and hose


I know the 650 is a bit much for the 305 but it only seems to bog down after the auto 700R4 shifts from 1st to 2nt. Just a lil, not to bad. I'll work that out later. But I just drove it back from my brothers, about a hour and 45 minutes, ran just fine. Thanks for all your help everyone but trying and replacing every sensor, problem going on for years.. I just had to give up on it.