Today I learned the wiring in this car is HELLLLLLLLL!, I rewired d17 19 d21 to the MAP sensor on the TB. the motor is a d15b single stage vtec obd1. Running on a p28 chipped with a decent p08 basemap and tune.. I regapped all plugs to 0.44 but im having a lag/hesitation in most gears.. brand new map sensor. TPS sensor is fairly new also. Clubbed inc burnt the p08 base map to the chip and it ran great at first. then idle went whack, cel kicked, popped MAP sensor code #3 obd1, replaced with brand new functioning sensor, reset ecu ( didnt pull fuze but disconnected battery for 30 min with key on. after time had passed, car started amazing, no cels, idles at 900 rpm smooth. go to drive, and its hesitant as in gear at times then will run like a scolded dog at other times. in the same RPM band it will stutter and go. no CELs at all? motor is a JDM d15b single stage vtec p08 head, p28 ecu, as explained, just wired MAP sensor today. everything else seems to be functioning proper..

is anyone familiar with the JDM d15b obd1 timing? I've read to go by d15z1 motor, then d16z6 guide, then so on so fourth. so my question, does anyone KNOW, that has done, helped do, knows without a doubt what belt it is? or should I just buy an adjustable cam gear and new belt and go from there?

 

have you replaced the iacv. You're asking alot of different questions

 

So your running a P08 basemap tune for a jdm d15b vtec? That doesn’t seem correct, the p08 map is a nonvtec gas saver like 90hp.

 

Did it run fine on the old ecu? Have you checked basics like ignition timing and making sure your plug wires are in good shape? Any vacuum leaks?

 

Should be running a p28.....ON A P28. But I guess since its chipped a little fine tuning won't hurt.

 

I'm running a y7 with a p28

 

I think you are confusing the P06 D15B7 ecu (102 BHP) for the P08 which is the JDM D15B vtec ECU. Or maybe the P05 D15B8 (92 BHP) ecu is the one you are thinking of.

P28 is the D16Z6 ecu not the JDM D15B single vtec ecu. P28 runs the D15B a little rich from all the old timers findings. And thats why they would chip an ECU and run a P08 basemap when they had the D15B vtec motor.

The belt will be determined by the tensioner you use. If I recall one tensioner has a larger diameter than the other. So if you use a D15B7 tensioner you would use the B7 106 tooth belt. If you use the Z6 tensioner then you use the 104 tooth belt.

From what I've seen most people find the 104 tooth belt too tight so I believe the JDM stock tensioner is more in line with the D15B7 tensioner.

 

Is that so? wow, interesting. Wonder what the jdm ecu code is...

 

The 103 tooth D15Z1 belt is the correct belt to use for an obd1 vtec d15b. Nothing else. The mechanical timing is also set the same as the D15Z1.

No stock map with idle the engine right, I even had issues using the jdm p08 ecu. It will need to be tuned to idle correctly.

 

Is the JDM P08 ECU an OBD2 ecu?

Why would the JDM ecu not run the JDM motor is was meant for? That doesn't make sense to me.

 

It's the factory ecu for the obd1 d15b vtec.

 

I knew it was the factory ecu for the JDM D15B vtec. I just wasn't sure if it was obd1.

So being OBD1 I am even more confused the stock JDM ECU had troubles running the stock JDM D15B for you. That really doesn't make sense.

 

I had the same issue trying to use a jdm p30 and b16a in another hatch so I gave up trying to use jdm ecus and moved on.

 

You right Tom, I was thinking of the p06, nice catch and thanks for the info!