I'm getting CEL from knock sensor, please help.

[kchaazz]

Ok, so im driving to work yesterday and its raining like hell and all of a sudden, my cel comes on, so i check my logger and its the knock sensor. So, when i get to work, i check it to be sure it didnt come unplugged somehow and its plugged in. I just replaced it because i was getting phantom knock bad, the new sensor didnt fix my pk but 3g lifters did the trick. ok, well, the thing is, i tried resetting my ecu and the knock sensor works fine for a few minutes according to the logger, then up goes the cel again! so it gives me 9 counts of knock with each little blip of the throttle now. well, i got mad and unplugged the knock sensor and just revved in neutral and what do you know? 9 counts of knock !
so, is my ecu dying or what? please help me, guys.


thanks, charles

 

[andymoraitis]

Charles,

Are you sure the knock sensor was torqued properly and hooked up correctly? Sounds like it's either defective or improperly installed. I would try replacing it with another new knock sensor as you also may have received a non-functioning piece. If you replace it with a new knock sensor and it still does the same thing, I would start looking at swapping another ECU to see if it makes a difference.

Let us know what you find,

Andy

P.S. In the future, please use a more descriptive title about the real issue as there are some highly qualified tuners on the site who aren't necessairly wisemen, but would be able to help.

 

[44pirate]

I had a similar situation with 9 count knock. That is a default the ECU use's when it doesn't see the Knock sensor. I had taken mine out completely to check it. When I reconnected back to the harness I had mistakenly connected it to the california emission connector that is right next to the knock sensor connector. They look similar. You can, with little force, plug it in the wrong one. I have a 92 not sure if this applys to a 90.

 

[Mike Marnik]

my car was doing the same thing when my capacitors began to leak. Is it showing any other cel?? I would pull the ecu and check to see if the caps are leaking at all. eventually the car will get worse and worse and eventually not want to start good luck and post up pictures of the ecu if you cant tell.

 

[kchaazz]

Update,

Well, I pulled my ks off today to go exchange it for a new one, but before I went to the Advance Auto Parts store, I decided to ground the ks to the battery and plug it in. Well, I start my car and the cel was gone and on my logger it said that the ks code was no longer active. So, I then started logging for knock and revved the car a couple times and the 9 count deal is gone? So, perhaps there was a problem with the connections or something or possibly the ks wasnt grounding to the block. Also, when I put in the sensor, I cant get a torque whench in there to be exact, so I just hand tighten it then give her a quarter turn with the wrench, which is ok, right?
I mean, I dont want to go too tight and induce phantom knock, right?

Also, its a good point that checking the ecu for bad caps was noted, I think it should be checked regardless of whether or not its the probelm just to catch possibly leaky caps before they destroy my ecu.

Thanks, everyone, for your help, Ill let you know if the promlem persists.

 

[Mike Marnik]

I know when i was having the same problem with the ecu and knock sensor that it would come and go. i could go a day or two or more with out it then bam it would hit. i would let the car sit overnight and in the morning it was fine go figure after i while it got more frequent and then finally was there all the time i would still check the ecu asap.

 

[kchaazz]

Update 2

Well, the ks problem is still gone, but i pulled my ecu to check it and my caps are leaking, the board doesnt look fried, but the brown gunk is there, its an eprom too, so i really dont want to lose it. im gonna get caps asap, but where can i get them replaced? Any electric repair place, or what?

 

[andymoraitis]

Go head and PM our Wiseman Steve who can help you with capacitor repair.

Glad you're working towards a positive solution.

Andy

 

[Mike Marnik]

Go head and PM our Wiseman Steve who can help you with capacitor repair.

Glad you're working towards a positive solution.

Andy

Yep pm steve like andy said he did a great job cleaning up my ecu and replacing the caps. Since its an eprom i would have him socket it at the same time also. Good luck!

 

[1gcrazy]

First off what's socketing an ecu? Also, why wouldn't mitsu create a recall on the leaking caps?

 

[kchaazz]

Yep pm steve like andy said he did a great job cleaning up my ecu and replacing the caps. Since its an eprom i would have him socket it at the same time also. Good luck!

Right on the mark there, id really like to get the stage 3 chip while im at it, just comp for the 66occ injectors and such to ease tuning and get a better timing curve for starters.

 

[Mike Marnik]

First off what's socketing an ecu? Also, why wouldn't mitsu create a recall on the leaking caps?

look it up and i dont know why theres no recall its probally because the cars are 12-16 years old

 

[andymoraitis]

Right on the mark there, id really like to get the stage 3 chip while im at it, just comp for the 66occ injectors and such to ease tuning and get a better timing curve for starters.

Why stop at custom timing tables only? I have custom A/F maps as well and no other fuel control and it works like a champ. Drop me a PM if you need a hand.

Andy