how to test knock sensor
Thread Starter
Burning Brakes
Joined: Jul 2013
Posts: 1,027
Likes: 30
From: Granite City Illinois
how to test knock sensor
My car has been pinging lately or knocking, on acceleration and right when it shifts gears. Its an 84 auto car.
I know the egr isnt connected up, but it never did it before. My oil temp gets high, about 225 degrees while the engine is around 200 even.
But I think the first thing I should check is the knock sensor, if its easy enough.
Someone qouted me $60 to test it
and said he used a voltmeter. I want to see if the engine is being controlled by it so I need a different test.
DMM`s I have, timing light I dont have. Any suggestions?
P.S. the car had a bad head gasket almost 2 years ago I think it was, might have been bad since I bought it a year before it got real bad. Blue Devil still working.
I know the egr isnt connected up, but it never did it before. My oil temp gets high, about 225 degrees while the engine is around 200 even.
But I think the first thing I should check is the knock sensor, if its easy enough.
Someone qouted me $60 to test it
and said he used a voltmeter. I want to see if the engine is being controlled by it so I need a different test.DMM`s I have, timing light I dont have. Any suggestions?
P.S. the car had a bad head gasket almost 2 years ago I think it was, might have been bad since I bought it a year before it got real bad. Blue Devil still working.
Last edited by ToniJ1960; May 28, 2016 at 09:21 PM. Reason: P.S.
Melting Slicks
Joined: Dec 2009
Posts: 2,244
Likes: 290
....with the timing light pointed at the balancer.
I'd hook up the egr again. It doesn't hurt your power.
I had some spark knock issues last year, seems like the engine was lugging because the torque converter locks up in 2-3-4gears. I unplugged the ttc connector & the knock is mostly gone. I'm looking into a kit that locks up the converter only in 4th & at around 55mph.
Gas isn't what it used to be either.
I'd hook up the egr again. It doesn't hurt your power.
I had some spark knock issues last year, seems like the engine was lugging because the torque converter locks up in 2-3-4gears. I unplugged the ttc connector & the knock is mostly gone. I'm looking into a kit that locks up the converter only in 4th & at around 55mph.
Gas isn't what it used to be either.
Team Owner
Joined: Sep 2003
Posts: 25,413
Likes: 2,745
I believe that early KS should OHM 100K +/- 5K terminal to housing.
I believe that many defeated the KS by disconnecting the ESC module that listens for the knocks. There should be threads.
I believe that many defeated the KS by disconnecting the ESC module that listens for the knocks. There should be threads.
Last edited by WVZR-1; May 28, 2016 at 10:05 PM.
Melting Slicks
Joined: May 2014
Posts: 2,898
Likes: 592
From: New Port Richey FL
My car has been pinging lately or knocking, on acceleration and right when it shifts gears. Its an 84 auto car.
I know the egr isnt connected up, but it never did it before. My oil temp gets high, about 225 degrees while the engine is around 200 even.
But I think the first thing I should check is the knock sensor, if its easy enough.
Someone qouted me $60 to test it and said he used a voltmeter. I want to see if the engine is being controlled by it so I need a different test.
DMM`s I have, timing light I dont have. Any suggestions?
P.S. the car had a bad head gasket almost 2 years ago I think it was, might have been bad since I bought it a year before it got real bad. Blue Devil still working.
I know the egr isnt connected up, but it never did it before. My oil temp gets high, about 225 degrees while the engine is around 200 even.
But I think the first thing I should check is the knock sensor, if its easy enough.
Someone qouted me $60 to test it
and said he used a voltmeter. I want to see if the engine is being controlled by it so I need a different test.DMM`s I have, timing light I dont have. Any suggestions?
P.S. the car had a bad head gasket almost 2 years ago I think it was, might have been bad since I bought it a year before it got real bad. Blue Devil still working.
I suppose you could test a Knock sensor with a DMM by seeing if it makes a minimal voltage or Resistance change when someone makes a Knock.
But honestly Timing lights are cheap enough new even cheaper at Garage Sales and thrift/Pawn shops. The test is very easy put the timing light on # 1 cylinder, Check the timing is correct (remember to disconnect the EST plug) if base timing is good. turn off car reconnect the EST plug. start car rev. motor observe the timing mark should move some, Than raise idle to about 1500 / 2000 RPMs hold steady there look at timing mark have someone tap on the Head Bolt above the Knock Sensor with a long socket extension and small hammer, timing should jump with the taps.
Last edited by s carter; May 28, 2016 at 10:15 PM.
Team Owner
Joined: Oct 2004
Posts: 81,241
Likes: 3,063
From: altered state
St. Jude Donor '05
Get the EGR working could solve your problem
What the difference between him charging you to ck it and buying a new one. Save your $ for now
Having the oil temp a litle higher than coolant isnt abnormal
What the difference between him charging you to ck it and buying a new one. Save your $ for now
Having the oil temp a litle higher than coolant isnt abnormal
Last edited by cv67; May 28, 2016 at 10:08 PM.
Thread Starter
Burning Brakes
Joined: Jul 2013
Posts: 1,027
Likes: 30
From: Granite City Illinois
Thank you everyone. I can get a timing light I guess, but I havent checked timing on a car in so long and it was a `different` brand.
If I can find the timing marks I can do it. Should I get some chalk or a white crayon?
Anyone have a photo of where the knock sensor is?
The egr solenoid isnt hooked up wasnt when I got the car. One of the thin hard plastic lines snapped on it too. So this should all be corrected no doubt.
What bothers me is hearing four or 5 raps or knocks or whatever. Wouldnt the computer catch it before that many?
The tcc isnt hooked up on the car but hasnt hurt it in the three years I had it. It has a broken pigtail and no vss so I know it never worked since I bought it, and drove it home from Michigan to St Louis.
If I can find the timing marks I can do it. Should I get some chalk or a white crayon?
Anyone have a photo of where the knock sensor is?
The egr solenoid isnt hooked up wasnt when I got the car. One of the thin hard plastic lines snapped on it too. So this should all be corrected no doubt.
What bothers me is hearing four or 5 raps or knocks or whatever. Wouldnt the computer catch it before that many?
The tcc isnt hooked up on the car but hasnt hurt it in the three years I had it. It has a broken pigtail and no vss so I know it never worked since I bought it, and drove it home from Michigan to St Louis.
Race Director
Joined: Apr 2002
Posts: 10,036
Likes: 346
From: Anaheim CA
Just in front of the starter above a shield bolted to the oil pan rail. My car is an '86, so it might be different (knock sensor location is the same):
Not having the TCC connected will affect your gas mileage. You do need the VSS to make it work.
Not having the TCC connected will affect your gas mileage. You do need the VSS to make it work.
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Thread Starter
Burning Brakes
Joined: Jul 2013
Posts: 1,027
Likes: 30
From: Granite City Illinois
Not as much as those leaky o rings did though, but Im still working on things as I go with this car, at least it didnt get parted out.
Race Director
Joined: Oct 2008
Posts: 17,982
Likes: 1,074
From: Lansing MI
Would you put new wiper blades on a car that had a broken windsheild ????
Seriously ...... forget about the knock sensor until your tcc is functioning properly. That's good advice even though it may not be the advice your looking for.
Seriously ...... forget about the knock sensor until your tcc is functioning properly. That's good advice even though it may not be the advice your looking for.
Last edited by PatternDayTrader; May 29, 2016 at 07:42 PM.
Race Director
Joined: Oct 2008
Posts: 17,982
Likes: 1,074
From: Lansing MI
At no point did I get the impression this was an excessive amount of spark knock. If excessive is the correct description of the condition, then it won't be a knock sensor problem anyway.
Team Owner
Joined: Oct 2004
Posts: 81,241
Likes: 3,063
From: altered state
St. Jude Donor '05
got a Toni here