Michaelfinn95

This originally started last friday, I was on my way home from work on the interstate when the engine stuttered a bit. I didn't think anything of it and kept driving. Later that night when I was closer to home I stopped for gas, then started back on the way home. As soon as I tried to accelerate out of the parking lot the engine loses power, I let of the gas and it goes back to idle. Tried one more time, got up to second gear and it happened again, only this time the engine stalled. Pulled over and tried to crank the engine and it would not start, waited 30 seconds or so and then tried again. Still wouldn't start, so I gave it a little gas and it finally started back up. It will idle fine when this happens, but as soon as you accelerate it bogs out. And it only dies this after driving it for more that 20 minutes. Also, when turning on the ignition after all of this, the fuel pump still primes the engine.

I know thats a long story and hard to read, so here is the just of it, the engine bogs out in low gears when accelerating after driving for 20 minutes.

I have not done any troubleshooting yet due to the lack of time. The car has new wires, plugs, distributor is about 1 year old, air filter, fuel filter is 8 months old, stock fuel pump.

Thanks in advance for the help!

Former User

Which of the two D15B VTEC engines do you have?

What ECU?

What CEL codes are thrown? You would only know if the CEL works.

Michaelfinn95

I want to say the ECU is a P06 or P26. Ill double check that this evening.

Its not throwing any codes.
The CEL does work. It comes on when priming the engine then goes of when done.

D15B out of the JDM VTI, not sure what the difference is there. If there is an article about it, I would love to know.

Former User

You probably mean P28, but do check.

This^ may be the D15Z1 engine equivalent rather the D16Z6 equivalent. If so, you have the wrong ECU, assuming you have a P28.

Check the head code:

https://honda-tech.com/forums/honda-.../#post48684945

https://honda-tech.com/forums/honda-...-here-3210150/

Also, check the mechanical timing, and whether unplugging the O2 sensor eliminates the issue.

Michaelfinn95

I apologize, thats my mistake... P08 or P28. I want to say it has the P08 in there more but I will check. Also, I will look into the engine a little more. This is what the shop that installed it told me it was:
"D15B VTEC (JDM)"
"92 VTi Auto--------------------------------P08-1"
However it is not an automatic transmission.
I am going to take the distributor off tonight and clean it, it has quite a bit of oil on and possibly in it due to a bad valve cover gasket and cam seal.

Thanks for the help BTW.

Former User

Post the head code and ECU code when you have time.

If the head code were P07, then you have the VTEC-e engine, which requires the P07 ECU.

Michaelfinn95

Will do, I get home at 9:30 CST so it will be shortly after that when I post them.

Michaelfinn95

Engine Head Code: P08


ECU: P28


Also found this... Maybe cracked header??

Former User

The ECU and engine seem properly matched.

The cracked header almost surely is making the engine run rich. Check for fouled plugs, and fix or replace the header.

TomCat39

Other than the alleged claim in the "post your head code", I have not ever found any evidence to indicate there was a vtec-e only version marked D15B. Even the non vtec D15B appears to be the carb version.

I've been trying to find some solid indications of all the variations of the D15B stamped JDM motor and for solid evidence so far I've only found 3 versions, carburetor non vtec, vtec, and dual vtec (vtec + vtec-e). I still suspect a fuel injected non vtec may be have been made but I am struggling to find solid evidence of it.

If you have any solid references please point me towards them.

The vtec-e JDM vti's appear to have been 1.6L not 1.5L

Michaelfinn95

If I replace the header I am going to replace the entire exhaust system, any suggestions on brand and type? I am looking for a nice low tone, nothing ricey and annoying.

Nave43

I would suggest buying the longest resonator you can find in your chosen diameter. Then acquiring a decent twin loop muffler. Have an exhaust shop fill in the gaps with piping add flanges/ hangers and you have a nice quiet performance exhaust. Just no mandrel bent piping plz. DC makes a good header, the ebay ones are pretty much DC clones. Any aftermarket header is going to make the car louder though so keep that in mind.

Former User

Is the D15Z1 (P07) or D16Y5 (P2J) a vtec-e engine?

Tyler Malan

I think the z1 is

TomCat39

As far as I know they both are but are stamped "D15Z1" and "D16Y5" not "D15B". Or am I misunderstanding?

Former User

There's an OBD2 D15B VTEC-e engine (P2J). I assumed that there is also a JDM OBD1 D15Z1 VTEC-e (P07) equivalent, but I could be wrong.

tony_2018

There is a d15b that has the vtec-e. Not much to go on but they are out there.

Former User

OBD1?

Michaelfinn95

So would the cracked header cause this issue? or is it just a contribution to it?

I will have the Mechanical Timing checked on monday, if there isn't an issue there, where would I need to look next? Its got good fuel flow, haven't check the pressure yet but the fuel pump sounds really strong still.

I can clean things and see if that helps (i.e.: fuel pressure regulator, map sensor, spark plugs, etc.) Do you think any of that would be worth the time?

I have heard the the Main Relay can be intermittent like that, is that a possibility or is that myth?

When I get home tonight I am going to check the spark plugs for fouling, I will clean when they are out also. What can I use to clean the FPR with?

TomCat39

Do you have a solid reference to point me towards for the D15B OBD2 vtec-e JDM engine? I know the information on Wikipedia is questionable and I have only found sales for the ones I mentioned previously.

If you haven't tested the pressure as per the FSM, how can you say it has good fuel flow?

Former User

https://en.wikipedia.org/wiki/Honda_D_engine#D15B

Michaelfinn95

Its a guess due to the fact the the car runs fine for a while before I have these problems. The fuel pump has no problem priming the engine when the car is cold or hot from what it seems. I guess I need to get a pressure gauge from autozone and test it. What is the FSM?

Nave43

If you suspect the main relay just pull and solder it, cant hurt and only takes 5 minutes.

TomCat39

Sorry Ron, but wikipedia only shows nonvtec carb D15B, vtec D15B and dual vtec D15B. That's the 3 I mentioned. and only the dual vtec (3 stage) is OBD2, the regular vtec is OBD1 and the Carb is PGM-Carb controller. No indication of a D15B vtec-e only motor in any obd format. Thus I question the accuracy of wikipedia and have been trying to find more than just mere claims to support the idea of a D15B vtec-e only motor in either the OBD1 or OBD2 flavor or both. No luck so far. Thanks though.

Fair enough. However, making assumptions without testing can be very problematic. I suspect in this case, your guess is probably quite accurate.

One thing that is supposed to change when car warms up that is not electronic on these OBD1 cars is the FITV. You might look into doing the FITV test once the cars warms up. If it is stuck open or closed, which ever the case is (don't remember off the top of my head) it can be too much for the IACV to compensate and cause issues only once the car is warmed up. It's rarer to mess up this way but is possible. Usually it causes symptoms when cold.

Former User

Correct.

The JDM OBD2 3-stage VTEC D15B engine, however, offers both VTEC-e and regular VTEC functions.

If one swaps this OBD2 JDM engine along with a D15Z1 P07 ECU into an OBD1 Civic, does it run well and only use the VTEC-e function?