Alright here goes. In no means am I a noob with Honda's, but I can not figure this one out for the life of me. We installed a D15B7 into my friends 93 Hatch for a DD. Well we installed the motor and had everything wired up in less than 2 hours..We were good to go. Upon cranking the car we had 2 CELS. One was an O2 sensor, and the other was the MAP sensor. I installed the O2 sensor and that CEL went away. I then had to install the MAP, because the motor came from a car that had the MAP on the fire wall, so I wired it up and that CEL went away. We have no CELs now of anykind. Heres the problem..Under any kind of load(above 3000 rpms) the engine cuts out. It pops, and has no power. We checked the compression and it was well within specs. We even removed the cat from the exaust system and the problems still remains. Hell my friend even bought a new distributor,plugs,wires,rotor & cap. We have tried both the P06 and a P05 ecu and have the same problems. Is it possible to have a blown headgasket and still have good compression #'s. Any help would be greatly appreciated.

 

That really sounds like a timing problem. I would check and make sure you are not a few deg off. Also you migth have a fuel injector sticking open causing a rich condition. But I would check the timing first and then go from there

 

damn jj, i hope ya'll figure this out, if not, i have another motor you can try if you want, if it works, you can buy it then if you want, cuz i dont know if it runs or not, but yeah, i was gonna say you might try doing the timing again, but i remember turbo said that you did it right, and the distributor thing, where you can move it all the way front and back, and it does nothing, still makes me want to say timing again. thats the only thing i can think of that wouldn't let it go above 3000, except limp mode, but you would have a CEL if that was the case right? ugh, i'm not helping, let me konw what yall find out, and if you need that motor, later,

 

Thanks guys, but the timming is dead nutts. Hell it starts right up, and runs with a slightly high idle. The idle is kinda screwy too though. It loops up and down. If you block up the EGR hose it idles almost right. It seems to be pointing to a falty headgasket, but the compression #'s dont seem to support that theory. Any more ideas guys?

 

Im guessing basically it's acting like a 3k rev limiter, only more abrupt and violent?

Since you've already replaced most of what I would have done, now we trickle down the line in other directions...

My next guess is fuel, or lack there of... Sticking or faulty injectors... A fuel pressure guage will not display this, since the regulator is there to return unused fuel to the tank. Above 3k RPMs the injector rate increases to compensate for the increase in engine rotational speed. If the injectors cannot open or close at the appropriate rate, or are sticking closed, you're experiencing a "fuel cut off" similar to your rev-limiter, only more violent because it isn't predicted by the ecu.

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Otherwise, here come the lame suggestions.. Make sure the alternator is rotating freely (but not loosely.) A jammed up old alternator with too tight of a belt could seize up an engine under low RPMs.

Tear the head off and check the valves and springs? Unless you can confirm this engine ran 100% fine before the swap, maybe under load the cam isn't kicking the valve closed like it should, causing a lack of compression under load and speed?

There's a handfull of other wierd things, but these are just brainstorming ideas? Random suggestions? Eh...

Good luck!

 

Thanks Hater those are some good ideas that I haven't thought of. Boy this is the way Honda-Tech is supposed to work. When we swapped the engine, upon initial start up we noticed that a few injectors were spraying fuel between the injectors and the fuel rail. So I grabbed a set off the shelf and we installed those. I bet the ones we put in are seizing up. They have been on the shelf unprotected for a year or so. Luckily I have plenty more. I will give the injector replacement a try. I will update as soon as I know more. Thanks guys.