[J450N]

My stock boost guage was never hooked up when the engine swap was done. Lately the guage has started to move around and show either + boost and other times vaccum. Is this a bad ground? My shifter cables werent hot so I think the engine/tranny ground is ok.

What is wrong here? My guage is NOT attached but likes to show boost, the needle goes halfway up the guage and stays there for an hour or so durring a drive.

 

[billwot]

Where is it disconnected?

If its disconnected at the pressure sensor, or on the PIM circuit, it will read full boost all the time.

bill

 

[Byron]

Possibly the wires that would normally connect to the pressure sensor are shorting out somewhere.

By the way, you need to physically check the chassis to tranny ground cable under the airbox if you even suspect there is a possibility of it making a poor connection. If any control cables ever get warm due to that ground cable, it will manifest itself in far greater way than just making them warm, and it will only be when the starter is running.

 

[Sang]

Where is it disconnected?

If its disconnected at the pressure sensor, or on the PIM circuit, it will read full boost all the time.

bill

mines disconnected at the pressure sensor but it shows atmospheric pressure all the time. i think that's the first big hash mark from the bottom. not full boost?

 

[J450N]

there is no line running to the guage for pressure. I dont know if it is electircally hooked up in any way, Im not familiar with the stock boost guage

 

[billwot]

The OEM gauge does not have a "line for pressure." It is 100% electric.

bill

 

[billwot]

mines disconnected at the pressure sensor but it shows atmospheric pressure all the time. i think that's the first big hash mark from the bottom. not full boost?

If the hose is dosconnected at the pressure sensor, then the gauge always read atmospheric.

If the harness is disconnected, it will read full boost, and you will get fuel cut.

bill

 

[Sang]

^ ahh, i see the light now, haha. thanks for clearing that up for me.