morbid
Hard-core CEG'er
Ok... this issue is really pissing me off, and I'm running out of ideas. Here's the problem:
My car has run unusually slow since I got it (15.8-16.0 quarter mile - stock). I've since added headers and a bunch of other performance stuff... and it STILL runs 15.8-16.0!
Even though I've had datalogging capabilities for a while... I never thought to check the knock sensor, until recently. As soon as I get on the gas... the knock sensor reads positive up until around 4,000rpm, then goes negative until around 6,600rpm. From 6,600-7,000rpm, it reads 0 and I actually get a bunch of timing. Below 6,600rpm... I have no timing. This happens when it's cold or hot out... and with part throttle and WOT.
So... here are some things I've done to troubleshoot it... and some stuff I fixed. But I still have a big "N" shaped knock sensor reading when ever I get on the gas.
* Oh... first off. I don't have any CEL codes.
* To eliminate the possibility of my brenspeed tune being the problem (and to support my thoughts that this problem has been around for a long time), I put the factory tune on. Datalog looked the same.
* To eliminate/reduce the possibility of it being a true ping/knock, I ran a full tank of 100 octane. No change to datalog. This, from what I've read here, should have also eliminated EGR as a suspect.
* I've had a rattle in the engine bay for a while... which I thought was coming from my relocated IMRC. Turns out it was my waterpump (reducer cone came off the housing and was bouncing around in the pump. I was really hoping this was my knock problem... but it didn't do a thing.
* From searching, it looks like hardly anyone has ever had a knock sensor fail... but since a new one wasn't that expensive, I got a new one. Also... a couple threads in the archive said to put a plastic washer inbetween the block and the sensor to reduce the over sensitive sensor. The new sensor with a plasic washer on both sides didn't change the datalog.
With the WP rattle gone... there is only 1 other sound which *might* be causing mechanical knock. There's a "ticking" sound coming from directly under the center of the UIM, under the 2nd runner group from the TB. From what I've read, this is not uncommon for the Contours, and isn't bad either. But from that sound location, I think it could be injectors, valve train, and that EGR box thing (which is covered in oil) is under there too. Could one of those items cause the knock sensor to go nuts? I think the tick is loudest at idle.. but I'm not sure if the engine sounds are drowning it out off idle... or if the tick is less loud off idle.
This knock sensor is very frustrating now. I'd really appreciate any help or suggestions!
My car has run unusually slow since I got it (15.8-16.0 quarter mile - stock). I've since added headers and a bunch of other performance stuff... and it STILL runs 15.8-16.0!
Even though I've had datalogging capabilities for a while... I never thought to check the knock sensor, until recently. As soon as I get on the gas... the knock sensor reads positive up until around 4,000rpm, then goes negative until around 6,600rpm. From 6,600-7,000rpm, it reads 0 and I actually get a bunch of timing. Below 6,600rpm... I have no timing. This happens when it's cold or hot out... and with part throttle and WOT.
So... here are some things I've done to troubleshoot it... and some stuff I fixed. But I still have a big "N" shaped knock sensor reading when ever I get on the gas.
* Oh... first off. I don't have any CEL codes.
* To eliminate the possibility of my brenspeed tune being the problem (and to support my thoughts that this problem has been around for a long time), I put the factory tune on. Datalog looked the same.
* To eliminate/reduce the possibility of it being a true ping/knock, I ran a full tank of 100 octane. No change to datalog. This, from what I've read here, should have also eliminated EGR as a suspect.
* I've had a rattle in the engine bay for a while... which I thought was coming from my relocated IMRC. Turns out it was my waterpump (reducer cone came off the housing and was bouncing around in the pump. I was really hoping this was my knock problem... but it didn't do a thing.
* From searching, it looks like hardly anyone has ever had a knock sensor fail... but since a new one wasn't that expensive, I got a new one. Also... a couple threads in the archive said to put a plastic washer inbetween the block and the sensor to reduce the over sensitive sensor. The new sensor with a plasic washer on both sides didn't change the datalog.
With the WP rattle gone... there is only 1 other sound which *might* be causing mechanical knock. There's a "ticking" sound coming from directly under the center of the UIM, under the 2nd runner group from the TB. From what I've read, this is not uncommon for the Contours, and isn't bad either. But from that sound location, I think it could be injectors, valve train, and that EGR box thing (which is covered in oil) is under there too. Could one of those items cause the knock sensor to go nuts? I think the tick is loudest at idle.. but I'm not sure if the engine sounds are drowning it out off idle... or if the tick is less loud off idle.
This knock sensor is very frustrating now. I'd really appreciate any help or suggestions!