VPC Chance # 2

[supraguy31]

Ok all, I decided to install the VPC once more today. Car fired right up and I drove it around for about 15 minutes without any Problems at all. Idled at 14.7 and When I drove it, It ran around 14.4 to 15.0 and Boosted without fuel cut.

Ok, Now here is the Strange part,

I pulled back up to work and turned the car off, Went in for about 3 Hours and then came back outside. I started the car up and the Idle seemed to Drop down to 16.0 but Idled fine. Problem is if I even think about touching the gas, It will drop down to ---- on the A/F gauge and will not move reguardless of how I adjust the VPC or SAFC. I had to drive it home today with the A/F levels at ----. Sputtered all the way home. As soon as I let off the gas, The A/F moved back up to about 15.8. Im guessing it has something to do with the Throttle or something.

I adjusted the SAFC from 0 to +50
I adjusted the VPC and No change.

With this Information, Does it sound like the Pressure Sensor or something else?

Thanks for all than can Help
Robert

 

[starscream5000]

Have you checked the wideband sensor to ensure that it's working properly?

 

[supraguy31]

Its working fine. when I had the VPC off the car, I put the Stock Electonics back on and set everything back to Original. I Drove it around for a few days like that and never had a Problem, Wide band read correctly until I re-installed the VPC

 

[Adjuster]

Sounds like you have a short somewhere. Or a bad sensor. If the short is on the PCB, your not likely to fix it. (Inside of the VPC box.)

 

[supraguy31]

How do you check the Sensor to make sure?

 

[Bondango]

How do you check the Sensor to make sure?

Have you checked the car for codes??

If you hardwired the VPC i would be checking the wiring and also the Resistor for the air temp fix. there is also a resistance check for the Intake temp sensor which is on a datasheet somewhere... i need to dig it out.
If your pressure sensor was out you can test the voltage quite easily...will also need to dig the voltage chart out.

But i would definately check all the wiring/connections if its been hardwired.

 

[Bondango]

 

[supraguy31]

The VPC is connected to the Field Harness. The only thing Hard Wired in is the SAFC to the VPC harness.

I dont have any Codes and No check engine Light

 

[Bondango]

The VPC is connected to the Field Harness. The only thing Hard Wired in is the SAFC to the VPC harness.

I dont have any Codes and No check engine Light

Check those connections then. and do the pressure sensor test as above.

 

[dbsupra90]

just curious- where do you have the map sensor mounted?

 

[supraguy31]

Its mounted right above the engine at the back of the firewall with the Small line going into the back of the Intake. Thats the only place I have tried to install it. Do you think its a bad place for it?

Temp Sensor is mounted on the back side of the Intake pipe

 

[supra8795]

That is where mine is located at and i have no problems at all. Where did you mount the iat sensor at?

 

[jtamulis]

Sounds like a wiring problem. Make sure you give it a GOOD ground.

A dead sensor would be dead 100% of the time, I don't think it's that
maybe your AIT is getting heat soaked when the car is let sit for a while?

What happened to you friend who had a VPC running perfectly, since he
is local couldn't he help you troubleshoot?


Jeff

 

[supraguy31]

He is stumpted also. His is connected like mine and he is Pushing over 400HP easy with his.

 

[supraguy31]

Are you talking about the Grounding on the Harness for the safc.

There isnt any type of Grounding wire for the MAP or Temp Sensor. Not one that I have found anyways. Connect the Main Harness up to the Engine harness, Connect the ECU to the Main Harness, Connect the Harness that comes from the Pressure sensor to the back of the VPC and connect the other harness to the small harness coming from the Main harness. Tap the wires needed for the SAFC.