Hopefully someone can answer some questions I have about the fuel pressure up vsv on my 87 7M-GE Supra. I have been having a hot start/heat soak issue, and I think I have finally found out what is causing it. I think it is the fuel pressure up vsv, because when you start it when it is hot, and pull the vacuum line from the vsv off of the fuel pressure regulator the idle instantly rises and smoothes out, and when you put it back on the idle drops to below 500 and it gets really rough. When the line was pulled off of the regulator there was vacuum in the line. I was able to repeat this test about ten times with the same results every time.
Now here are some questions that I have:
1. I noticed that there is nothing about the fuel pressure up vsv in the online 1990 TSRM for the 7MGE, but in the 87 TSRM there is information. I looked in the Electronic Parts Catalog, and saw that the 89 plus N/A Supras don't have the vsv, and it looks there is nothing attached to the vacuum line coming off of the fuel pressure regulator. So does this mean that the regulator just recieves constant atmospheric pressure, and has no vacuum applied to it?
2. This question goes along with my first question. Would there be any harmful side effects of disconnecting the vacuum line off of the fuel pressure regulator and let it go to the atmosphere, and leave the vsv down there with nothing attached to it's vacuum lines?
3. Instead of needing a replacement ($80 from Toyota), is it possible that the vsv is just clogged and stuck in the vacuum position, and therefore needs a cleaning so that it can switch back and forth between vacuum and atmospheric pressure?
Thanks in advance for any answers,
Gavyn
Now here are some questions that I have:
1. I noticed that there is nothing about the fuel pressure up vsv in the online 1990 TSRM for the 7MGE, but in the 87 TSRM there is information. I looked in the Electronic Parts Catalog, and saw that the 89 plus N/A Supras don't have the vsv, and it looks there is nothing attached to the vacuum line coming off of the fuel pressure regulator. So does this mean that the regulator just recieves constant atmospheric pressure, and has no vacuum applied to it?
2. This question goes along with my first question. Would there be any harmful side effects of disconnecting the vacuum line off of the fuel pressure regulator and let it go to the atmosphere, and leave the vsv down there with nothing attached to it's vacuum lines?
3. Instead of needing a replacement ($80 from Toyota), is it possible that the vsv is just clogged and stuck in the vacuum position, and therefore needs a cleaning so that it can switch back and forth between vacuum and atmospheric pressure?
Thanks in advance for any answers,
Gavyn