I recently bought a VAFC II with the Frog(something) PnP harness. I'm getting a new header this week and then going to get dyno-tuned. I decided to save myself some $$$ by installing just the PnP harness myself. I left the VAFC completely detached. Well, after completing the install, my CEL is on and the car is sputtering badly. I have no idea what the CEL code is because I'm worried about driving it.

So the question is, would installing just the PnP harness cause this? I really can't see why since it's not plugged up to anything yet, so no values should have changed.

A side note, I also noticed after lifting my hood that coolant had sprayed all over the engine bay. This includes on the strut bar, the IM, the TB, the ExM heat shield, rad shroud, CAI, hoses, etc. I mean EVERYTHING is covered with white dots. I checked the rad and it's still full. Is there something else that could have sprayed everywhere and then dried white?

 

If no one has any ideas, I guess I'll just remove the harness and see if things go back to normal. My threads never seem to get many responses.

 

question- you sd you have no idea what the cel code is because your afraid to drive it? Ive read on other threads that you could use the jumper method to test for cel even in the 5th gen. (I could be completely wrong about this.) Id goto your neighborhood Autozone and ask to borrow their reader. They had the loan a tool thing for awhile. Even if loaning their reader is not per their policy, i bet if you talk nicely to them (or slip them a 20) they may let you borrow it.

 

OK, I pulled the codes myself. CEL is blinking 22 followed by 3. ATTS is blinking 60 followed by 10. Where's that damn table that says what the codes mean?

 

When you install the VAFC without the harness, you cut some wires which run from the ECU to the VAFC to the engine sensors. The harness does the job without cutting the wires. The VAFC works by reading the output from the ECU, then makes the corrections that you specifiy, which then sends the alterned signal to the injectors, ect. It has to have the line run into the VAFC and out of the VAFC. You can't just splice into and add a wire running to the VAFC and leave a direct connection from the ECU to the sensor. So, with the harness installed, it's the same as hacking the wires as if your going to install the VAFC, but you haven't connected the VAFC to the cut wires yet. Basically, a few of your wires are open and not completing the circuit that the ECU sends and recieves from the sensors. Just plug in the VAFC and leave the settings alone. It should run fine.

 

The manual specifically states NOT to drive the car until the initial setup of the VAFC is complete. It says it can damage the engine.

 

Do not drive the car.... but have you tried plugging it in and starting the car to see if the CEL codes go away??
How hard is it to install the harness??
Can you not plug it in when you take the car for its tune??

 

The harness is cake to install. Just pull up the carpet, unscrew the 4 nuts, pull the footrest, unplug the 3 harness plugs, install harness, and then repeat in reverse order. Problem is that the 4 nuts were a PITA because of location and room to work.

I'm thinking about doing all of that and just leaving the ECU flopping, without the VAFC harness plugged in. Then Friday or Saturday when I take it to get tuned, unplug the ECU and plug in the harness right there in the shop.

 

Have you tried plugging in the VAFC and just starting the car to see if the CEL codes go away?
Would hate for you to go in to get it tuned and find that it costs you double because they have to repair the faults before the actual tuning can take place.

 

OK, I unplugged the harness and put everything back to factory. CELs are gone and engine runs normally again.

Guess I'll leave it like this until I take it to the shop.

I'm still not sure what sprayed all over my engine bay, leaving white spots everywhere. I wiped it all down so I can tell if it happens again.

 

Initial setup is simply telling the VAFC that you have 4 cyclinders, and then with the car off, press the gas pedal to the floor so that it calibrates to the TPS voltage. It has NOTHING to do with changing any fuel settings or anything. You hook up the VAFC, turn the key to accessories, then follow the instructions for initial setup. After that, you can drive around just like stock if you leave the fuel settings alone.