VG30 knock sensor

aaronford · Aug 14th, 2003, 09:11 PM

Ok, this is on a Merc Villager, but it is essentially a rebadged quest with the 3.0 V6, so here goes. The check engine light came on and ther code reader said it was a knock sensor circuit malfunction. Is there a typical problem with this? I would rather not remove the intake manifold if the is something simpler to start with. I looked in the manual and it showed the harness and which pin in the connector, but there are two connectors with the same 4x2 configuration coming from that harness. It showed a pic of the harness but not of the connector. The setup in this van looks identical to a Pathy or Hardbody, so if you have experience with this, please share. Thanks

nissannut · Aug 25th, 2003, 04:04 PM

I have a 94 Quest. Unfortunately the check engine light did not come on, I had to check the codes. This code will not light the light on a 94. It has been bad for years..

You need to test the knock sensor at the harness connector for resistance. Mine shows none.. I bought a new knock sensor ($100.) Bosch makes it...

I plan on changing soon, its mounted under the intake on the top of the block..

lewisnc100 · Aug 26th, 2003, 07:17 AM

OK, I think I can help. Sounds like you already know exactly where the knock sensor subharness connector is, just to the left of the left row of spark plugs. When you disconnect the harness and look inside the knock sensor subharness connector you should see two rows of 4 pins. The pin you want is the lower right pin, number 5. Check resistance between the pin and engine ground, should be 500 - 620k at 77 degrees F.

nissannut · Aug 26th, 2003, 07:55 AM

I checked mine.. no resistance.. I will have to remove intake to confim the sensor itself is bad...

aaronford · Aug 26th, 2003, 09:01 PM

Well, I forgot to mention that this code also popped up with an EGR flow fault. So the prob may be in EGR flow and thus causing a ghost fault in the knock sensor. Thanks for the info, though

lewisnc100 · Aug 28th, 2003, 01:22 PM

I'm betting it's a phantom error and not worth the time to check the subharness until you get the EGR error cleared up. I get a knock sensor error with an intermittent vent control valve error and others get it with the purge control valve. Clear up the EGR valve and your knock sensor error will probably go away.