I have vacuum every where else. how can I not have it at the throttle body? Its the two right on top.
no vacuum at tb!
- Thread starter 87supraturbo19
- Start date
Thank you. Wow! never even thought about that. So once you open the throttle there is no vacuum. what is the point of these? the one goes to the thermostat housing to the bsvp thing. What is that thing anyways? i need to buy a new one. I broke one of the plastic connectors off.
No, once you open the throttle there is vacuum. Ported vacuum refers to vacuum sources located upstream of the throttle plate. The two you have are for the BVSV and the EGR. Since both need to be off at idle their vacuum sources are located on the atmospheric side of the throttle plate when it's closed. When the throttle plate opens slightly the ports are uncovered and exposed to manifold vacuum.
The BVSV sends fuel vapor that was stored in the charcoal cannister (it came from the fuel tank) to the intake to be burned. It's an emissions thing. If that were allowed to happen when the engine was cold or at idle the mixture would be upset. The BVSV keeps it from happening with cold coolant and the ported vacuum keep it from happening when at idle with hot coolant.
The EGR also needs to be off at idle or idle quality will be effected. It also needs to be off when the engine is cold or above about 4000 rpm. That's done by ported vacuum when hot and by the ECU controlling a solenoid valve during the other two situations.
The BVSV sends fuel vapor that was stored in the charcoal cannister (it came from the fuel tank) to the intake to be burned. It's an emissions thing. If that were allowed to happen when the engine was cold or at idle the mixture would be upset. The BVSV keeps it from happening with cold coolant and the ported vacuum keep it from happening when at idle with hot coolant.
The EGR also needs to be off at idle or idle quality will be effected. It also needs to be off when the engine is cold or above about 4000 rpm. That's done by ported vacuum when hot and by the ECU controlling a solenoid valve during the other two situations.
Wait, didn't I already cover all of that?
Yeah, I did:
Seriously though, 87SupraTurbo19, don't feel too bad I almost posted the same thing a very, very long time ago... Luckily I spared myself the embarrassment and caught myself just in time. :biglaugh:
Yeah, I did:
CRE said:
Seriously though, 87SupraTurbo19, don't feel too bad I almost posted the same thing a very, very long time ago... Luckily I spared myself the embarrassment and caught myself just in time. :biglaugh: