gene

oh its one of those. that is a EMI issue. not a hard code but a pre code. the ecm is seeing a spec just outside of that sensor, whether its noise feeding back to the ecu or a dirty or bad sensor reference ground. common on alot of pr3/pw0 ecus. those ecu's are very sensitive to noise, but ive had that happen to me once and turns out the ecu was bad

DORKO

well maybe...


im running open header at the moment, no interior, no carpet, and its been wire tucked. so everything is sitting on the passenger side floorboard, tiewrapped to my cage.


any suggestions?

Fabrik8

You might have a problem from the wire tucking. Once you start moving the location of wires, and bundling things together that weren't bundled together before, you may find you have unexpected noise issues. I'm not really a fan of wire tucking, I was an electronics technician for too many years to accept the problems/compromises with noise and service access that are created when doing wire tucks. If the wiring is stock and works great, don't cut it, extend it, move it, change it, whatever. Any modification is usually asking for reliability and performance problems, and that's a risk that you choose to accept.

You only need the one wire coming from the plug going to the ECU, and it should really be a shielded cable like the stock knock sensors use. You've verified the pinout of the knock sensor at the ECU, and done all of that stuff, so that you can try another ECU without damaging it, correct?

DORKO

i can try another pr3/pw0 ecu, but i dont know anyone with a JDM obd0 b16.


and the wire is shielded. its running directly from the KS, to the ECU. i believe its a 14-16ga. wire.

i mean its crimped/heatshrunk and everything.

but the ECU is sitting on the floor, on top of the fusebox from under the hood.

like i said i didnt do the wire tuck, but this is the only problem im having at all.


its retarded. ill try another ECU.

gene

sorry never a big fan of crimping... soldering is the only way for excellent connections. btw the shielding on the wire only works if its grounded

DORKO

ok, well then , its insulated


and i bet if i solder it, the CEL will still be there.

xeno

try another ecu ... i did this fucking song and dance and even assumed the motor must be knocking ... and the fuckin ecu was bad ..but you said the two wires on the knocksensor are running to one? one is the ecu wire and one is the ground i believe.

DORKO

no on obd0 KS, there is only 1 pin. on the obd0 KS plug there is only 1 wire that runs directly to the ECU.


im using a obd1 KS plug right now. and its running straight to the ECU.

Fabrik8

I know you're probably talking about the red/yellow/blue insulated butt splices, and you're right, they're bad. But the fact is that using a proper uninsulated crimp splice, which starts as a "U" or "V" and crimps into a "B" shape, is far superior to soldering. Soldering is easy and cheap, and you don't need any special parts, so that's fine, but it's not superior to crimping by any means. Solder joints wick flux up into the wire strands, and cause horrible corrosion problems (solder flux is pretty corrosive), and the soldered portion does a really poor job of transferring vibrational fatigue across the joint. Basically, soldered splice joints corrode and break. The crimp splice I'm talking about is the type that Honda uses to splice a few wires right at the ECU, such as the shield for the knock sensor wire, and are usually brass. I use them for all of our race harnesses, and I've never had one fail at the joint, unlike the solder joints on the rigged-up dyno harnesses. These crimp splices are very widespread across the automotive industry, which is why I know about them and the reasons they are used.

If you've never had a soldered wire splice fail, good for you. It's only a matter of time, and the car may never see enough use for the solder joints to fail. But don't say crimping isn't the way to go, because the entire automotive and motorsport industry would disagree with you. Underhood harnessing is not the place to solder.

gene

i can agree and disagree. ive never had a solder joint fail but most guys use the standard "butt splices" for splicing so i was referring to that as a poor way of splicing. i can agree about the corrosion issue but then again how long would it take for the corrosion to eat up the wires? years? and copper corrodes too i can agree that crimping the ecu pins is the way to go (i do that when i can). But i am a mfg rep for Tyco/Amp and Molex and crimping pins is reliable but that isn't why mfg's go that route, they do that for cost savings. its faster and easier. so before i get off topic about this... we are talking about splicing/crimping in two different categories. im talking about harness joints and lap joints and you are talking about pin termination, either way, its always better that wire nuts or butt splices



but to get back to dorko, try another ecu