Ok well it seems that the car is not building boost at all. The boost gauge will only read right up to 0 vaccum and that is right about at 9k rpm. Has anybody had any experience with this happening to them. I am wondering if it could just be that the bypass valve is stuck open. Any help or ideas to what it could be would be helpful. I have done only a brief check of the vaccum lines and at first glance everything looks in place and no kinks. Thanks for the help in advance. I think if that is the problem I may just throw on the extra Turbo XS RFL that I have laying around here.

 

Belt and couplers are all in good shape?

Does the car feel like it's not boosting or are you just going by what the gauge says?

Is this a new install, have you had it in boost before?

 

where is your boost gauge tapped into? does the car feel faster? with the car off is the gauge at 0psi?

 

All of what is mentioned above is good.

Either it is not making boost, loosing boost or the gauge is not working.


Make sure the gauge is working.....is it stronger? Has it seen boost previously? Have you had it on a dyno?

Make sure the connections are tight and the blowoff valve is not open. Anyplace where boost can be lost should be checked.

Make sure the pulley is keyed and the belt is snug.

 

belts are snug. couplers are all in good shape. when the car is off the gauge reads zero.

it feels stronger but not nearly as strong as it was when the s/c was first installed. it feels like it is getting power starting around 8k and it used to really pull much earlier in the powerband. the car has not been dyno'ed but this difference in power is completely noticable from what it was.

I still need to check the bypass valve as that was the idea i felt was most likely the source. I should get to that tomorrow but wanted to get other ideas as to what or where the problem could be coming from.


thanks again for all the suggestions.

 

Just interested.... did you ever get this problem fixed?

 

Bringing it back from the dead!

Kind of having the same problem. The car will boost fine when it's cold. But when it is warm, the engine will hit VTEC and "fall on it's face"- meaning it will bog and have no boost. I notice that my dipstick is always up about an 1/8"

Could it be loosing boost through the dipstick?

Could it be the by-pass valve?

What should I check?

 

Bump for some help.

 

Bumping again.

 

sounds like you have a boost leak. check the bypass valve for cracks and warps.

the dipstick pop out i believe is caused from boost entering the crankcase (search supra PCV or crank vents for solutions).

did you ever try an aftermarket BOV?