boost gage

soulreaver

New Member
Apr 4, 2005
15
0
0
when my car idles the boost gage reads -4. it wont go up when i rev it,it will sit there on -4 then jump up to over half way then go up normally the rest of the way when its in first and its being floored. when i take off like onto the highway and give it a little gas you can here the turbo charge but the gage doesent move . is this normal or is it broke or leak? anyone know
 

mkIIIman089

Supramania Contributor
Mar 30, 2005
3,061
0
36
Ohio
I don't know if it is malfunctioning or not but my car with looking at the stock guage behaves the same with hearing the turbo spool. I think its simply because of the range of the guage. -4 is not very much since I believe -16 - -21 at idle is best; driving its probably even more vacuum. So though you hear the turbo, it is still not enough to bring it above -4 at that point. I think its normal. Someone please correct me if I'm wrong.
 

Bigdough666

Picture Me Rollin
Apr 4, 2005
367
0
0
41
Corpus Christi, TX
Yea, the stock gauge is worthless. At idle my vaccum is around 18-20. With the stock gauge only reading 4, wtf is the point? And yea, its SUPER slow. Get a real gauge and you'll learn a lot more about how the car is boosting.
 

RIPDOTCOM

New Member
May 22, 2005
157
0
0
51
Tallahassee, FL
I dont know much about the turbo supra's but I do know that some boost gauges read in .hg and some read in psi. 4 X psi = about 17-18 .hg so that may be the answer. The supra gauge probably reads in psi both on vacuum and psi while typical boost gauges read in .hg for vacuum and psi for boost.
 

americanjebus

Mr. Evergreen
Mar 30, 2005
1,867
0
0
36
wa.
yea stock guage sucks my left nut, i will floor it and be at full boost and after a nap and a cup of tea the needle will finnally rise, the only time i ever see it on something other than -4 or full boost is on hills where i use medum throttle under load and i can wach the needle dance arround 0 to 4 psi.

yea stock sucks
 

chriso

Supranian
Apr 5, 2005
917
0
0
Bay Area, CA
My stock 87 gage would be slow to react when I initially start to boost then it would "jump" and finally start to move slowly. I replaced it twice with other 87 stock gages and had the same thing. I finally used an 89 stock gage and that one works smoothly the way it should. I will eventually go with an aftermarket gage and replace the stock one with a voltmeter from an n/a.