EF-YOU!

Noobie smokin a doobie
First time poster

Just bought a 93 cx sedan with a jdm vtec-e (d15b) in attempts to get extreme mpg. Long story short, the ecu i am currently running is a chipped p28 ecu, unknown mapping, 4k launch control, vtec kicks over at 5. Car kind of lags. Searched everywhere! (googled, honda tech etc.)

d15b, p07 head. thats all i know.

i've seen post saying that you would need a p07 ecu, bought one today and now i got cel. (havent checked cel code) although it does run a little bit smoother

Diagnoses? suggestions? anything helps thanks in advance

HondaPartsHero

Can you take a picture of your motor? I'm kinda confused on the one you have since there are a few variations of the D15B?

EF-YOU!

sorry thats all i got for now. it says vtec-e on the valve cover, p07 on head, d15b on the block

i can take more pictures tomorrow

hatchaddict01

he is correct he has a jdm d15b vtec-e it the same as a usdm d15z1, now with you p07 that ecu is looking for a egr valve and a 5 wire o2, and im willing to bet you dont have the control box for the egr and the wiring for it and also you probably have a 4 wire o2. ive been down this road with a coupe i bought for 200 bucks it had the same jdm d15b vtec-e in it and was on a stock p28 but ran like ****, i fixed it with a different engine cause i wasnt concered with mpg

aaronhume

is there a way to disable the egr valve in it? I am about to buy this same engine for my eg, and I have the ecu and all but the egr is my only concern for a CEL at this point.

EF-YOU!

yeah, whats the easiest, but correct way to fix this problem? I bought the car for cruising, not performance. i just want it to run right and save gas.

hatchaddict01

go to junk yard and find the egr control box and cut the harness to get the plugs and wire it in to the ecu and also run the wiring from the ecu to support the 5 wire o2 thats the correct way. othe then that get a p28 chipped with a p07 map and lower vtec engagement to 2500 you will be able to keep the 4 wire o2 and not use the egr

Former User

1) Pull the CEL codes.

2) How old are the plugs, wires, cap, and rotor? Have you inspected them?

3) Is the ignition timing set to spec?

EF-YOU!

cel code came to be the oxygen sensor.

just bought the car about two days ago so i dont know. it all looks new.

i am checking the timing tomorrow.

anywho, so i went to Fluid Motorsports in Tacoma, WA. Alex there said it could just be the o2 sensor, stripped it by trying to taking it out, then clipped the wires, and said it will be fine. They didnt have a p07 mapping for my ecu and said to just get new headers and o2 sensor. jeez. these guys. i only went there because the previous owner said corey the owner would put the p07 mapping in the p28 ecu. so now im running my p07 ecu with my cel. are they telling the truth? and this would not ruin the car in any way?
also when i run my p28 ecu, no cel. alex said also because its chipped... ??

sorry for the noob questions. what the heck do i do now?! thanks again everybody for being so helpful

EF-YOU!

hatchaddict01 was right,

it has a 4 wire o2, td-42u distributor if that helps any

so would the best route be:

1)get new o2 sensor (maybe new headers if i cant get it out)
2)get p28 ecu chipped (with p07 or p08 mapping?)

and go from there to see if any cel comes up?

biggest concern;
driving the car the way it is? (only way of transportation)
if it is okay, what ecu for now? p07/p28/does it matter?

EF-YOU!

bump

aaronhume

if you want my two cents, I would recommend buying a p07 ecu and sell the p28. this way you can run the 5-wire o2 sensor and use the engine as a proper lean-burn engine and save more gas than just swapping to a p07 fuel map. the p07 ecu actually has a separate processor just for the o2 sensor in it. however if you go this route you will have to figure out the EGR connection.

I am about to put this same engine in my 94 lx and am working on ideas for the egr myself.

EF-YOU!

Wished I saw aaronhume's post earlier.

But Brian from H & A imports hooked it up with a p07 mapping for just 30 Bucks!
I ask how long? He told me 20 mins. I wasnt even there for more the 10! Cool guys, great service.

Car runs great now thanks everone again.

aaronhume

let us know what kind of economy you get with just the mapping on that p28... I am very curious

EF-YOU!

Okay now what?!

Thinking everything was fine a little too soon.

It runs and drives great now. BUT, it died out 2 times on me today. When it dies out oil and battery light comes on. Why? I checked my battery terminals and everything is nice, tight and good. (like my gf)

I start it right back up and continue on.

HELP!! Maybe the ecu again?

EF-YOU!

bump because im stumped

EF-YOU!

It happened again! When it dies out, im in neutral. why is that?

Help! any diagnoses?