codyisanidiot

I have a d15b7 sohc with a Greddy td04h-15g turbo. The problem is, I'm not running a vtec head. When I reach five pounds of boost at resonible throttle, my check engine light comes on. I think it's because my e-manage is sending more fuel, raising my air/fuel to 11.3 but I have no vtec to use more fuel. What should I do? Re-flash my ECU? Or send my e-manage in? Please help.


Much appreciated.

waaBAAH

what ecu you running? the only way for anthing to do with vtec on your non vtec motor is if you are running a vtec ecu. COMPLETLY take vtec out of your mind if you do not have a vtec ecu.

what are you running for a map sensor? this is where i think you problem is.

ffa710

Im having the same problem. Im thinking its the mass air flow sensor. Would I be able to get one that would work with the turbo, or how would i go about fixing it?

waaBAAH

i have been out of the loop for whats required with changin yoru MAP sensor for it to see boost so please forgive me. i will try to point you in the right direction.

i beleive anyhtign more then 7 pounds would require some form of modification to your MAP sensor routing.

from there i know of two options.

one is a one way check valve that will allow air in a vaccum state and will not allow pressure (boost) to reach MAP sensor. you can find them on ebay or the like. (before haters hate on ebay..its just a one way check valve..i dont think ebay could mess up a simple design liek that lol). i beleive the correct name is MAP bypass or MAP check valve

option two is to relocate yoru map sensor... you will need a different throttle body from another car that has an external MAP sensor design. accords come to mind but dont know fitment on a d series from the accords f series. older generations civics might have an external MAP sensor. from there you mount a couple check valves inside the rubber hose from your MAP sensor to your TB. i heard fish aquarium stores carry these check valves. this is kind of considered the "ghetto" version but it can get the same result as option one.

F20B-CX

iTrader: (1)

You've got it backwards. An AFR of 11.3 is pretty far on the rich side.

Next, as far as ECUs go, the trick mentioned above about keeping the MAF from seeing boost is a hack way to do it. This method is used in conjunction with an FMU, which is the dark age way of fueling for turbos. It nukes your motor if you are boosting without going WOT; when not at WOT, the ECU takes a signal from the oxygen sensor, and drives the air/fuel ratio to 14.7:1, which is far too lean of a mix in boost. You will detonate and be buying a new engine. At WOT, you set the rate of gain, and you're in the approximate area you should be. The ECU has no idea what's going on.
The correct way to do things is to have an ECU chipped, and have it tuned by a reputable tuner. That way you can boost at all times without worrying about detonation. The stock MAP will suffice; it can read boost. Stock ECU cannot, and this is where piggybacks come from.

waaBAAH

i did have it backwards..i will change it on my side.

i would listen to f20b over my advice....i have been out of the loop for quite some time.

codyisanidiot

I found out the problem and it IS an ecu fuel map problem. Because the fuel curve was set for vtec, at 5500 rpms wot the check engine light would come on because I was running too rich and my ecu thought that my vtec, which I didn't have, wasn't working right. It would hold my air/fuel running rich, waiting for vtec to work.

Instead of fixing the piggyback, I bought a d16z6 head and a p28 ecu and used my same piggy back. I now have vtec, which is what my piggyback was made for, and the correct ecu for that piggyback as well. It was a lot cheaper than sending in my piggyback or buying a new e-manage ultimate.