WHAT THE CRAP>.... ECU under carpet

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No, J1 only affects the "aftermarket" chip. The area outlined where the chip is usually has nothing. When J1 is jumped, the ECU reverts to the installed chip vs the map already on the ECU. If you take out the chip without disconnecting J1, the engine wouldn't even run since the ECU has no map to read off of.
 
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so then usually the J1 isn't even "installed" or connected?

(sorry to rephrase what you just said, but I want to make sure I'm going the right direction)

the ecu is allready mapped for a factory motor. The issue is if this isn't a p08 like the motor calls for wouldn't I be screwed?
 
If you cut the J1 it may be a bad idea. We dont know what Base Map it was before the chip. It will revert back to what ever it once was (in which we do mot know) I would truly have a programmer look at it before I cut it.
 
In a stock ECU, J1 is not connected(everything in the outlined area is empty). It does not matter what base map was in it before because it will revert to a "stock ECU" state. So, if it's a P28 ECU, cutting it turns it into a regular P28 regardless of what chip is in there.
 
In a stock ECU, J1 is not connected(everything in the outlined area is empty). It does not matter what base map was in it before because it will revert to a "stock ECU" state. So, if it's a P28 ECU, cutting it turns it into a regular P28 regardless of what chip is in there.

but does the P28 have the same basemap as the P08 that should be for that block?

Thanks for staying in this thread. I don't mean to ask so many questions over and over again. But like they say, measure twice cut once
 
No, but at least you know what map it'll be running. My suggestion is to try running the P28 base map since it should run slightly richer, adjust ignition timing, and see if that reduces NOX.

J1 can always be reconnected. Cutting it will not permanently disable the circuit(as stated before, stock ECUs do not have this jumped to begin with).
 
a p28 is a usable ecu for the d15b, so if it is a p28, you should be good. p08 is the right ecu, but plenty of people run the p28 with no probs.
 
No, but at least you know what map it'll be running. My suggestion is to try running the P28 base map since it should run slightly richer, adjust ignition timing, and see if that reduces NOX.

J1 can always be reconnected. Cutting it will not permanently disable the circuit(as stated before, stock ECUs do not have this jumped to begin with).

would I want to retard the timing or advance it?
 
What if its a P06? (which is pretty common OBD1 chipped ECU) It will work too but no VTEC for sure.

I guess you can try it....but like I said before....hook up/fix the VTEC plugs
 
What if its a P06? (which is pretty common OBD1 chipped ECU) It will work too but no VTEC for sure.

I guess you can try it....but like I said before....hook up/fix the VTEC plugs

its running seemingly normal without vtec (as it isn't connected). My thought is cutting the j1 and rerunning a smog test. If it passes, reconnect j1 and get a new chip, get vtec connected. Right now it is running "ok" without it. For now I just need to get it to pass smog. The "performance" stuff can all be figured out after the stupid thing becomes legal to drive.

and do I want to retard the timing as it will cause less fuel thus equalling the extra fuel of having it potentially too rich?
 
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SON OF A @$#@#($. !!!
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So I pulled this thing out with the wiring and found this whole section that isn't connected to anything. I am thinking and hoping these wires are all vtec related. All of the non yellow wires are not connected to anything in the vehicle

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You wont use a few of those. But four are for 02 sensor I know that. Thats your problem, you have no 02. Find a pin out and hook up those wires are you should be good.
 
You wont use a few of those. But four are for 02 sensor I know that. Thats your problem, you have no 02. Find a pin out and hook up those wires are you should be good.

any idea which four go to what sensors? I know one of the o2 sensors is wired via speaker cable and a twist tie (no crap...). I imagine there would also be a downstream sensor?

Would I wire these wires directly to the sensor?
 
also, I don't know if anyone noticed. The ECU has a PR4 stamped on it. It couldn't be a PR4 though as it wouldn't have the obd1 harness setup.
 
I noticed that earlier and talked about it in a post but not sure if its just a ECU cast (like a general casting) or if its specific. If it truly is a PR4....thats an LS ECU so its not VTEC ready and means the chip has some VTEC map on it
 
I noticed that earlier and talked about it in a post but not sure if its just a ECU cast (like a general casting) or if its specific. If it truly is a PR4....thats an LS ECU so its not VTEC ready and means the chip has some VTEC map on it

That is my fear with cutting the j1. Would the pr4 have the mapping needed to run the d15b?
 
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