I know there are alot of mechanics and people that know alot about cars on here so heres my question.

I rebuilt my friends head on his gsr b/c he bent some valves. While taking it apart i noticed there wasnt a connector for the knock sensor on the back of the block.

His motor is obd2 but was converted to the obd1 p72 ecu when it was put in. I have heard that if you are running obd1 that the knock sensor isnt necessary but wasnt too sure about that.

The car has been running good before and pulled a 14.3 with bolt ons. I have heard that if the knock sensor wasnt hooked up than it would run in limp mode but havent seen that yet.

So my question is... is it ok to run with no connector on if it was converted to obd1? Also i know that the knock sensor retards timing up to 3 degrees i think but wasnt sure if this would do anything. I heard you could splice the wire that is used for the knock sensor coming out of the ecu and run it to it but if its not necessary id rather skip it.

 

depends on what ecu he's running. If its chipped and knock sensor disabled. Is it throwing Cel??

 

Its not chipped (as far as we can see.) and its the obd1 p72 ecu. It does throw a cel about 5 min or so after it runs which im sure is probably the knock sensor since it doesnt come on right away but havent checked it yet since its obd1 and i hate checking obd1's lol.

So he has had the swap for about a year now and its ran fine. I was just wondering if running no connector on the knock sensor would hurt anything. I figured it would put the car in limp mode or run funny but ended up pulling a better 1/4 mile than i thought.

Car is just i/rh/e p72 obd1 ecu with no tune.

 

Anyone else have any info? anything that helps would be appreciated

 

well i have the same gsr in a eg just check what code the check engine ligth gives you its easy to check go under the glove box and theres a green boot with 2 plugs get the plug that has to pins or wires better said and jump it with a wire with the ign on the on position and the ligth will flash you the code if its the knock sen dont waste your time to wire it just get a p28 chipped revs to 9grand also doesent see the intake butterflys the gsr has if you have the stock intake mani is your vtec kick in?? start by checking the code n let me know wassa

 

i'm pretty sure you are right. check the codes.

it is highly unlikely that you'll actually be able to hurt anything because factory honda knock sensors are about as useless in knock prevention/protection as blind people in flight school. as long as your timing isn't sent to the moon while running boost/nitrous.. you should be okay

 

I have heard that the p28 doesnt read the gsr butterflys as well. So i guess the gsr manifold will still work the butterfly's wont open? I guess if he wants to put out the money for a skunk2 mani he can go that route. Also its the p72 obd1 ecu and vtec kicks in at 4.5k. I will check the code tomorrow when i go over there and see what it shows. Thanks for all the help. I know hes been driving it without it hooked up for over a year and still ran a 14.3 with i/h/e which i thought wasnt bad for what he had...

 

yah tell him to get a p28 chipped thats what i run you really dont need knock sensor by the time the motor knocks that bitch is toast so just keep ears open for a knock haha but he be fine yah swap that stock manifold with a skun2 or vitor x if hes gonna boost let me know what it throws up

 

Ya friends got a b18c5 in a 92 hatch and hes running the p28 with the s200. Is the hondata the main chip you use to chip the p28's or are there cheaper ones. Hes got kids and i dont think hes got the extra money to spend on that but ill tell him thats an option. I think he'll run it how it was for now since it ran fine and i just rebuilt the head but ill tell him whats up. Also he has hasport mounts and i heard those throw the knock sensor as well so id say their pointless once you mod.

Ill post the code tomorrow. It won't start right now also. lol think the starter went out but were checking our options. It used to just click and after about 20 clicks it would finally turn over but now i just clicks. Gunna bang on it a bit and see if i can free it up... maybe its just stuck.

Thanks for the info. Also have you tracked the car yet or any 1/4 mile times. My friend with the b18c5 in the 92 had a gsr (98) in it before and only pulled a 15.2 in the 1/4. Was suprised when he pulled the 14.3 Thats why i thought his ecu was chipped at first too. lol

 

Ok I didnt check for the code yet. We got it all together and tried to start it and it sounds good and turns over but doesnt start. (close but doesnt start) When the distributor is more forward it would backfire and when i have it all the way back it just turns over and almost starts... Does this sound like maybe the cams might be a a tooth off from the crank because the cams are good just so ****ing hard to align the crank up with the block still in the car. It was what we thought to be top dead center when we took the head off. Im not sure what else it could be. Any help would be appreciated!

 

Would the car still turn over fine and sound good if the cams were a tooth off from the crank? The cams are on time but you just cant see the crank with that plastic cover in the way. The backfire while the distributor was back and just cranking when its in the middle or forward is leading me to believe this but not sure how much room there is between the valves and pistons to where they could both be a tooth off.

If anyone has had the similar problem or could know what else it could be i would appreciate it.