Vacuum hose – Free fix
Here is an oft overlooked fix you can do in less than 30 minutes. It eliminates a hidden performance/mileage thief. Unhook each vacuum hose end, snip off ¼ - ½ in and remount (assuming there is enough length in the subject vacuum line). This puts an unstretched tighter portion of hose on the vacuum outlet and reduces all of those fractional vacuum losses that add up. If this helps, you can then get new rubber or silicon hose and do a more lasting replacement.
I’ve always had lingering issues with my 7mgte for mileage and somewhat lame off idle throttle response. It just wasn’t what I’ve experienced for 20+ years with my 5mge’s. In the course of replacing my remote oil filter lines, a vacuum line was left unhooked. The feel and vac readings while this was unhooked pointed to a possible vac leak as my ongoing problem. So I took a casual look/see at the lines for a leak. When I pulled one off, I saw that the end remained stretched out in the shape of the line it mounted on. So, I went around and snipped off the ends as I noted above. Voila, yahoo, whoopee, I finally got the 7mgte I was looking for. The improved off idle throttle response and feel was very noticeable. I may have got another 1” or so of idle vacuum (the gauge markings are very small) to about 18” at 2500’ above sea level. I clearly have quicker vacuum recovery during routine driving pedal movements. I will report later about the mileage.
Here is a link to a 7mgte vacuum hose replacement DIY.
http://www.cygnusx1.net/supra/install/vacuume_hose.html
Here is an oft overlooked fix you can do in less than 30 minutes. It eliminates a hidden performance/mileage thief. Unhook each vacuum hose end, snip off ¼ - ½ in and remount (assuming there is enough length in the subject vacuum line). This puts an unstretched tighter portion of hose on the vacuum outlet and reduces all of those fractional vacuum losses that add up. If this helps, you can then get new rubber or silicon hose and do a more lasting replacement.
I’ve always had lingering issues with my 7mgte for mileage and somewhat lame off idle throttle response. It just wasn’t what I’ve experienced for 20+ years with my 5mge’s. In the course of replacing my remote oil filter lines, a vacuum line was left unhooked. The feel and vac readings while this was unhooked pointed to a possible vac leak as my ongoing problem. So I took a casual look/see at the lines for a leak. When I pulled one off, I saw that the end remained stretched out in the shape of the line it mounted on. So, I went around and snipped off the ends as I noted above. Voila, yahoo, whoopee, I finally got the 7mgte I was looking for. The improved off idle throttle response and feel was very noticeable. I may have got another 1” or so of idle vacuum (the gauge markings are very small) to about 18” at 2500’ above sea level. I clearly have quicker vacuum recovery during routine driving pedal movements. I will report later about the mileage.
Here is a link to a 7mgte vacuum hose replacement DIY.
http://www.cygnusx1.net/supra/install/vacuume_hose.html
