scoobywagon45 Posted April 30, 2013 Share Posted April 30, 2013 (edited) My wagon has some leg in accelerating. It is a stick and around 2,000 rpms there is a lag, it does not want to go any faster. To me it feels like an auto tranny not wanting to downshift on a hill. After 3400 rpms the leg is gone and the power is back. It has a completely rebuilt engine, seals, gaskets, a new crank and one new rod. I found out the answer to this problem and it was the knock sensor. Below the knock sensor someone helped me place a small donut shaped gasket and this immedialetly fixed the problem. I just got a new knock sensor today and thought that it would solve the problem for good but it is back. The homemade gasket is not underneath the knock sensor. Has anyone had a problem like this and could it be part of the rebuilt engine? Edited April 30, 2013 by scoobywagon45 Quote Link to comment Share on other sites More sharing options...
lmdew Posted April 30, 2013 Share Posted April 30, 2013 Is the CEL on? If the Sensor is bad, you should get a CEL. Did the new sensor get properly clocked so it's setting flat? Did you read the resistance of new sensor before you installed it? Just some thoughts. Quote Link to comment Share on other sites More sharing options...
scoobywagon45 Posted April 30, 2013 Author Share Posted April 30, 2013 the check engine light was on before then I reset the ecu, and installed the new sensor and it was torqued down to the correct amount. Could this be part of the ecu relearning timing? Quote Link to comment Share on other sites More sharing options...
scoobywagon45 Posted May 1, 2013 Author Share Posted May 1, 2013 I put the small gasket back on today and it seemed to fix it. It just worries me that it thinks that there is a knock. Quote Link to comment Share on other sites More sharing options...
scoobywagon45 Posted May 1, 2013 Author Share Posted May 1, 2013 Nevermind did not fix the problem, does anyone know what the torque is on it? Quote Link to comment Share on other sites More sharing options...
mikaleda Posted May 3, 2013 Share Posted May 3, 2013 Hand tight plus a quarter turn, is what I torque knock sensors to. No gasket under the knock sensor that will cause problems since the - negative side is conects through the block. Make sure the sensor has a good clean connection to the block and is sitting flat. Also what code are you getting? Quote Link to comment Share on other sites More sharing options...
scoobywagon45 Posted May 3, 2013 Author Share Posted May 3, 2013 I dont what the number of the code was, someone else hooked up the reader. K thanks ill try it without the gasket underneath. Quote Link to comment Share on other sites More sharing options...
Fairtax4me Posted May 3, 2013 Share Posted May 3, 2013 Pretty sure it's 17ft-lbs which is basically just snug. 1/4 turn after hand tight may be a bit too much. Hand tight, put your palm on the head of the ratchet and turn your wrist and it will be tight enough. An actual code would be helpful. Some other possibilities: A dirty MAF sensor can cause hesitation like this. Vacuum leaks. A plugged PCV valve can cause all sorts of issues. When did it last get filters, plugs, and wires? Quote Link to comment Share on other sites More sharing options...
scoobywagon45 Posted May 8, 2013 Author Share Posted May 8, 2013 It has new everything, could this be part of the ecu? Everytime I reset the ecu it goes away for a little while and the it comes back again. Quote Link to comment Share on other sites More sharing options...
mikaleda Posted May 8, 2013 Share Posted May 8, 2013 (edited) Are you getting a knock sensor code? If you are I would think its probably a bad wire to the sensor or maybe a dirty connection. Edited May 8, 2013 by mikaleda Quote Link to comment Share on other sites More sharing options...
Fairtax4me Posted May 12, 2013 Share Posted May 12, 2013 If the code is for the knock sensor it's a resistance issue with the circuit. The ECU either can't detect the sensor or the voltage signal is out of range due to poor connection or corrosion. Quote Link to comment Share on other sites More sharing options...
scoobywagon45 Posted May 14, 2013 Author Share Posted May 14, 2013 solved the problem!! I just moved the knock sensor to a new location. Its nice to have a car that finally has some power! Thanks for all the input! Quote Link to comment Share on other sites More sharing options...
presslab Posted May 15, 2013 Share Posted May 15, 2013 Something in your engine is making a noise that is tripping the knock sensor. Quote Link to comment Share on other sites More sharing options...
scoobywagon45 Posted May 15, 2013 Author Share Posted May 15, 2013 nevermind it started back up again. could it be the rebuilt engine? everything just settling in still? Quote Link to comment Share on other sites More sharing options...
Fairtax4me Posted May 15, 2013 Share Posted May 15, 2013 Do you still have a CEL? It would be helpful to know exactly what codes are current. The issue may be due to another sensor. If the current code is for the knock sensor it could be a faulty sensor. Quote Link to comment Share on other sites More sharing options...
presslab Posted May 15, 2013 Share Posted May 15, 2013 Yes, you need to get the CEL code. Does the engine sound quiet? If it's got tappet noises you should check the valve lash. The knock sensor is a microphone, it could be hearing other noises and thinking it's knock. Quote Link to comment Share on other sites More sharing options...
scoobywagon45 Posted May 17, 2013 Author Share Posted May 17, 2013 The code was for a knock sensor, I cleared it by resetting the ECU, there is a noise with the engine but it does not come up every time. I can only hear it while it is idling and it is very slight, could this be piston slap? Quote Link to comment Share on other sites More sharing options...
mikaleda Posted May 17, 2013 Share Posted May 17, 2013 The code was for a knock sensor, I cleared it by resetting the ECU, there is a noise with the engine but it does not come up every time. I can only hear it while it is idling and it is very slight, could this be piston slap? How long has it been since you adjusted the valves? Quote Link to comment Share on other sites More sharing options...
scoobywagon45 Posted May 17, 2013 Author Share Posted May 17, 2013 I dont know I was not the one who rebuilt the engine, I do know that some new valves were put in though. Could this be the problem? Quote Link to comment Share on other sites More sharing options...
mikaleda Posted May 17, 2013 Share Posted May 17, 2013 It couldn't hut to check the adjustment Quote Link to comment Share on other sites More sharing options...
Fairtax4me Posted May 18, 2013 Share Posted May 18, 2013 Need to know year and engine size to know if valve adjustment is even possible. Still want to know if the current CEL is for the knock sensor. I have a feeling it may be something else like a dirty MAF sensor or maybe even a misfire because of fouled or old spark plugs. If the code is still for the knock sensor it's either a wiring issue or a bad sensor. Quote Link to comment Share on other sites More sharing options...
mikaleda Posted May 18, 2013 Share Posted May 18, 2013 Title 98 legacy, interferance adjustable valve clearance. Quote Link to comment Share on other sites More sharing options...
scoobywagon45 Posted May 20, 2013 Author Share Posted May 20, 2013 I cleared the CEL and it was for a knock sensor, I moved it up a bit to where the clutch cable goes by and that diminished the lag a lot. Going to move it to another place if I can. Quote Link to comment Share on other sites More sharing options...
Fairtax4me Posted May 21, 2013 Share Posted May 21, 2013 If the code is still for the knock sensor it's either a wiring issue or a bad sensor. Quote Link to comment Share on other sites More sharing options...
scoobywagon45 Posted May 21, 2013 Author Share Posted May 21, 2013 The code went away when I cleared it for the first time, it hasn't come back since, sorry I should have clarified that. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.