Hello all...

I am trying to sort out a problem I am having with a stock D16 ZC (SOHC Vtec).

The problem is simply this... It will idle (Although surge slightly) but as soon as the throttle body plate begins to open, it bogs and dies.

This is a non-turbo engine running a P-28 ECU.

Now, please read before making a suggestion...

Initially, I thought I had a throttle body problem so I cleaned and exchanged it with a good running engine in another car I have (Including the gasket)

Then I tested, and eventually exchanged the following parts:

MAP
IAT
FITV
IACV
Intake gasket. (3 times)
Intake
Dizzy
Wires
Injectors
Fuel dampener
Fuel Pressure Regulator
plugs
ECU
PCV valve
O2 sensor

I also checked every wire for continuity from each sensor to the ECU.

I also checked every hose running into the intake for leaks. (Hell, I even disconnected each one, one by one, and plugged the intake to see if there was a leak)

I have attempted an assorted variety of timing settings.

Basically, every part, minus the block and head has been swapped with a running engine and that engine is running fine.

The only difference between the two setups is that the good running engine has stock exhaust, and the one I am having problems with is running an open header and resonator.

I am just not getting it! It is a bone stock engine running a bone stock fuel map on a virgin P-28 that runs great on a similar setup, yet the engine is running so rich it fouls the plugs in a matter of seconds. I have even tried running different heat ranges of plugs.

So, anyone have any ideas? What the heck makes this engine run so rich? I dont have an A/F gauge to check how rich, but as black as the plugs are, I can safely say it is running rich...

Help a guy out...

Initially, I thought the problem was a vacuum leak, but I am now certain that I do not have one.