miltown

So i have a 1998 civic cx and just dropped a d16z6 in it after being in the garage for 3 years. Before being in storage it had a b16a2 and it was running fine. Today when I finished doing the swap in the afternoon and checked and rechecked everything before starting it, I go to turn on the key and I don't hear my fuel pump priming or my main relay clicking. I went ahead and did some research and found that it could be a main relay issue or fall of the pump fuse or my back up/radio fuse. I replaced all of them with new ones and im still having the same issue. So i dugged a little deeper and found the I can check to see if the fuel pump is working by putting a paper clip between pin 1and 7 or 5 and 7 on the main relay harness. When I did that, the fuel pump did prime. So i connected the new main relay back and i got nothing. I have used two types of ecus one is a p28 with a baseman for the engine and the other one is a p2p from an civic ex that i have as a daily.

Well as you can see Im in a bit of a frustrating situation as i don't know what else it could be and im coming to you guys to see if any one has seen this problem before and could help a fellow honda enthusiast with his problem.

Thanks again

Former User

You don't need a chipped P28 for the D16Z6. Please explain.

Do you have an OBD1-OBD2a conversion harness for the P28 ECU?


What CEL codes are thrown?

miltown

The p28 i have is chipped and i do have an obd2a to obd1 jumper harness on it. The only codes that the computer is throwing is oxygen sensor codes.

Former User

Chipped for what?

Post all the actual codes.

miltown

it is chipped for a d16z6 with a 255 walbro fuel pump.
the codes that i get are from when i hook up my p2p
those codes are p0135 and p0141
i haven't checked with the obd1 ecu by jumping the blue connector on the passenger side by where the computer goes

Former User

Why would you need to chip a P28 ECU that was already made for the D16Z6 engine?

Did you connect the crucial G101 ground on the thermostat housing?

For those two OBD2 CEL codes, check whether dash fuse 15 is blown.

Does the CEL work? If so, hook up the P28 and pull the codes. Post them.

miltown

The only reason why i used the p28 is because the car has a walbro 255 in it thats about it i know that it is already made for the z6 but just wanted to be right with the fuel pump you know.... I did rechecked my grounds and even recleaned them to make sure. I will check fuse number 15 tomorrow morning and i will also post the codes that it throws with the p28. Hey man thanks again for all your help and i hope that this helps.

tony_2018

I didn't know there was an option to configure the fuel pump. Damn must be bad ***.

miltown

is on crome. tuning shop did it for me for my b16 with a basemap, then i told him to reburn it so i can use for the z6 with the walbro pump.

mk378

If the fuel pump doesn't even turn on, you have a more fundamental electrical problem than having the fuel map wrong.

The properties of the fuel pump don't matter for tuning. The fuel pressure is controlled by the regulator on the fuel rail, not the pump. Use a stock regulator. Third-party adjustable regulators cause a lot of problems.

miltown

It does turn on if I use the paper clip on the electrical main relay harness. If I hook up everything back and go and try to turn it on I get nothing from the pump. I'm not using an aftermarket regulator is all stock.

Former User

P28 CEL codes?

Was fuse 15 blown?

miltown

Haven't checked those cuz I'm at work. As soon as I get out I'll be doing those things.

Former User

Be sure to check this too as you can't pull OBD1 codes if the CEL doesn't work.

miltown

P28 codes are 41 and 48. Fuse 15 was not blown.

mk378

If ECU is booting up to blink the CEL, it should also be going through the fuel priming sequence. Check the wiring between the ECU and the relay coil. The ECU pin supplies a ground to the relay which energizes the coil, closing the relay contacts which starts the pump. The OBDII main relay is considerably different from the OBD1 one, but the concept is the same.

Former User

You MUST be using the wrong D16Z6 basemap to get code 48 (VX O2 sensor).

miltown

So I just finished working on the hatch about an hour ago. The whole day I went through checking diagrams, checking fuses relays power and grounds. And nothing that I was doing seem to work. So I decided to completely start over. I redid my engine wire harness, clean the grounds again and reinstalled the wire harness. Decided to use my spare p2p and try it again. I went to turn on the ignition and the greatest sound I've heard this week the fuel pump priming sound and the sweet sound of the engine starting. I do wanna give thanks to all you guys who helped me through this I couldn't have done it without you guys. Thanks again.