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People say splice into the MAP sensor
Some say splice into the turbo pressure sensor
Some call it the pressure exchange solenoid.

Tried the map sensor, car just dies after being started.

http://www.surrealmirage.com/vrg3/ecupins/

The white/yellow wires on the HKS FCD need to go to the

F47.20 Pressure exchange solenoid T

Yes?

Interesting how this is an issue between you and another user in the last couple days.

No it does NOT go to the pressure exchange solenoid.

I'll try to spell it out.

Our ECUs are factory set for 8.7 psi boost. We want to up the boost because we have this AWESOME block that likes a beating.

We up the boost.

Well the ECU doesn't want us to boost past (i think) 12.7psi? (might be off a decimal or two on that one.) The MAP (manifold absolute pressure) sensor monitors how much vac/boost is in the intake manifold (in conjunction with the pressure exchange solenoid.) The map sensor signal is a 0-5v signal reported to the ecu. Once the MAP sensor sees 5v (12.7psi) for 3 seconds, the ECU enables fuel cut. What fuel cut defenders/defencers do is clamp that 5 volts to say... 4.9? (I think that's what vrg3's FCD does (Cheap Electronic FCD in the Turbo section) ((Been talked about ALOT)) Anyways since I'm rambling on about how stuff works and not answering your question, the FCD interrupts the MAP SENSOR SIGNAL WIRE. If you follow the instructions on the Chris P FCD the only thing you need to touch on the Pressure exchange Solenoid is the +12 V Yellow/red.

However you seem to be installing at the ECU so, If you have a diagram for your HKS FCD, You will want to interrupt the MAP signal wire (Input and out are VERY IMPORTANT in this part) B48.4 based off of Josh's website http://www.surrealmirage.com/vrg3/ecupins/

I don't mean to question your ability or put you down at all. But if you followed the directions of your FCD and of the installation instructions of the FCD on this site, then it should work bud. If it doesn't work, do you know for sure you have a working FCD?

Double/Triple check each of your wires from the FCD to the Harness. Maybe you didn't get proper +12 or +5 v? I know it's a pain in the ass to wire something to the ecu harness because of the limited space.

cj91legss wrote:Interesting how this is an issue between you and another user in the last couple days.

No it does NOT go to the pressure exchange solenoid.

I'll try to spell it out.

Our ECUs are factory set for 8.7 psi boost. We want to up the boost because we have this AWESOME block that likes a beating.

We up the boost.

Well the ECU doesn't want us to boost past (i think) 12.7psi? (might be off a decimal or two on that one.) The MAP (manifold absolute pressure) sensor monitors how much vac/boost is in the intake manifold (in conjunction with the pressure exchange solenoid.) The map sensor signal is a 0-5v signal reported to the ecu. Once the MAP sensor sees 5v (12.7psi) for 3 seconds, the ECU enables fuel cut. What fuel cut defenders/defencers do is clamp that 5 volts to say... 4.9? (I think that's what vrg3's FCD does (Cheap Electronic FCD in the Turbo section) ((Been talked about ALOT)) Anyways since I'm rambling on about how stuff works and not answering your question, the FCD interrupts the MAP SENSOR SIGNAL WIRE. If you follow the instructions on the Chris P FCD the only thing you need to touch on the Pressure exchange Solenoid is the +12 V Yellow/red.

However you seem to be installing at the ECU so, If you have a diagram for your HKS FCD, You will want to interrupt the MAP signal wire (Input and out are VERY IMPORTANT in this part) B48.4 based off of Josh's website http://www.surrealmirage.com/vrg3/ecupins/

I don't mean to question your ability or put you down at all. But if you followed the directions of your FCD and of the installation instructions of the FCD on this site, then it should work bud. If it doesn't work, do you know for sure you have a working FCD?

Double/Triple check each of your wires from the FCD to the Harness. Maybe you didn't get proper +12 or +5 v? I know it's a pain in the ass to wire something to the ecu harness because of the limited space.

I'm being told by 2 people who have installed them and have had them working that it's going to go to the pressure sensor, not the map sensor.

I wasn't trying to be a dick.

cj91legss wrote:I wasn't trying to be a dick.

Oh sorry, almost came off that way. It's just getting annoying how I keep getting a bunch of different things from people. I just wanted to verify and splice into the correct things at once. If it isn't the pressure sensor for sure and it's the map sensor then I need to get a refund on this HKS FCD.

After reading over what I said, I can understand what you mean. The map sensor and pressure sensor is the same thing. The exchange solenoid is seperate. Check out the other fcd diagrams.

Maybe you do have a bad fcd?

cj91legss wrote:After reading over what I said, I can understand what you mean. The map sensor and pressure sensor is the same thing. The exchange solenoid is seperate. Check out the other fcd diagrams.

Maybe you do have a bad fcd?

Gonna check in a bit to make sure it was done 100% correctly.

Did you buy it used?

cj91legss wrote:Did you buy it used?

Yea

You can get a new hks fcd on ebay for 99, or a turbosmart for 152.99 if you think its damaged.

cj91legss wrote:You can get a new hks fcd on ebay for 99, or a turbosmart for 152.99 if you think its damaged.

If I do anything like that I'll probably look into the PnP FCD kit that goes for like $55 on these forums.

Do you have any soldering skills? I just built myself vrg3s cheap electronic fcd. I spent lesst than 10 at radioshack in parts.

cj91legss wrote:Do you have any soldering skills? I just built myself vrg3s cheap electronic fcd. I spent lesst than 10 at radioshack in parts.

Soldering no.

No soldering skills. I just went over and checked to see if I wired it wrong. No go still. Code 45. How do I even know if this fcd is powering on? The "PNP" kit I'm seeing that gets wired under the hood looks like a nightmare. Doesn't look clean at all.



That look like the right color wire?

I would have to pull my panel and look. I wired my fcd in at the sensor.

Okay let me know

Does the power need to go to a specific spot?

No, any 12v ignition switched will work.

Okay good. I used the cigarette lighter.

Tried a different connection at the ECU got it to work...For a few minutes then it popped a CEL and boom...no more boost. So I put it back together. This is a nightmare. I know more people have installed these dang things. Chasing this is not fun.

Anyone who has INSTALLED an FCD?

I installed my HKS one at the ECU. I can grab a picture tomorrow if you need it.

Please

Kinda shitty picture, but it is on B48.4. Black wire, with a red and white on either side of it. Purple wire from the fcd goes there, green should hook up to the input.

Sent from my mind using telepathy

In your second pic, it looks like you were counting from the wrong side of the plug. It's that same row, but 4th position in from the opposite side (not 4th wire, since the 1st position is unoccupied).

Oh, and in case you wanted some sort of assurance, I have been running this for at least 5 years with 0 issues. It is kinda annoying to set up initially (at least without someone else to help while you drive), but works like a champ once you do.

Forgot to mention I switched to that black wire and got it wired it. No CEL or anything. Took it for a test drive all was good then about half a mile later CEL popped on and car wouldn't boost.

Something not set right on the FCD? I had someone tell me it was the black wire in a message on a face book group and got the input and output wired right and had no issues till a minute into the test drive.

Would die when it would try to hit boost.