I had my supercharger on for a while now and its been reading 0lbs of boost ever since. First I thought it was a leak in the vac. line but it wasnt. Today me and my friend tried out his greddy boost guage in my car with a thick rubber hose that came with it. We ran the line under my hood through the driver window with the hood not closed all the way so we know its not pinching the line. Ran it 3 times at 3 different T tap points and its all the same 0 lbs of boost. We cant seem to find out the problem. Can anyone help me out with this?

 

my guess... your belt..

can you hear the charger in the upper PRMS?

 

Yes, I can hear the blower whine when I punch it especially in the upper rpms.

 

where is the hose connected? does the car feel like it's making power with the sc?

 

Its connected to the vac line next to the FPR vac line. Yes, its making power especially in 3rd gear. I pulled my friend by ALOT. We use to be even before I put in the blower.

 

T-tap goes there..


How did you hook up your buddies gauge without a sending unit? Or did you use your sending unti and his gauge?

my next guess would be that your boost sending unit is jacked. contact whomever you bought the gauge off of...

told you, you should of bought mine,,,

 

We also thought the belt was slipping but its on pretty good. No signs of slipping.

 

I tapped it there also and its the same. 0 boost. We just hooked up the vac line on his gauge to see if it was boosting.

I was going to buy yours but the hurricane hit us bad and left me jobless for two weeks and I spent a ton on money recovering. Have to put money back in the bank till I feel secure again and then start buying stuff again.

 

if the car is boosting.... his gauge does the same as yours... then replace the sending unit or check your wiring... YOU do know that you need Constant power for your gauges to work properly... and when I say constant power I mean.. as soon as you turn the key to the ON position I. (the postion where you can use your radio/windows without the car running) the gauges should calibrate and come on... then stay on when you turn the key to position II and start the car. (not shut off and come back on when you start the car)

 

We both have mechanical gauges. My friends boost gauge works on his car but not mine. He has a Evo so I dont know if the vac. on turbo cars work differently. The store I bought my gauge from said that the mechanical one works fine and thats all I really need and the electric one just lets you set the peak boost so its not really necessary to have. So I dont know... Should I buy a electric one?

 

I actually had this happen but it was to a turbo vehicle. If you turn the car on and it shows vacuum and when you nail it in gear and it doesnt go into boost either you gauge is bad or you have a bad boost leak somewhere. Unless the supercharger isnt working (no belt), but you did mention you can hear it and feel the power difference. I would check for leaks, good luck, oh and thanks again for the CAI...

 

Can you give me Idea's from where its leaking? Ill go check it at work today and ask the shop forman to do a leak check. No prob on the CAI. I hope you enjoy hearing vtec kick in as I did. Mines so quiet now, But I love the whine.

 

A whining engine sucks!! lol ...a spooling turbo sounds better!!!

 

Whats the range on the booost gauge? if its a 30lb guage, then you might not see any noticable boost. SC cars make around 4psi with the the stock pully and perhaps 5-6 with hbp.

When the car is idling, is it pulling vacuum? should be like 20-23 in at idle with no vacuum leaks, at least that's where mines at. When you stab the accellerator, the vacuum should pop up to "0" or at the very least, something less than 20in vac.


A way to see if there is a vacuum leak is to get a can of carb cleaner or brake clean and spray it around the various vacuum hoses in the enging compartment. If there is a leak you will notice a change in the engine rpm's as well as how the motor is idleing.

 

I suggest using another vacuum source. Just T-off another vacuum hose and plug the one you were previously using, any vacuum hose will read boost and vacuum on a forced induction engine. Try and see if that works, maybe its the actuator on the blower elbow thats bad...

 

Are you sure that your bypass valve is operating correctly? It's the diaphram canister device on the side of the super charger. You should be able to see it move when you open the throttle about 1/3 and over. Or, try actuating it by hand, with the throttle open about 1/3 or above, to see if the car will build boost

 

Yeah thats what I was sugggesting, I mean if he hooks the gauge up to another vacuum source it should work, because a big vacuum leak will mess up his idle and he will notice it.

 

No!

...................they're both sexy!

 

You suck! lol

 

My gauge reads up to 20psi. It vac to 18-20. Yes when I WOT it does to 0 and normal driving it does to 10vac. Where should I spray the brake cleaner? On the outside? or in the tube?

 

It opens at idle. Shouldnt it be closed, then open to release pressure?

 

The vacuum will open the valve, zero psi and under boost the valve closes. Get long nose pliers and try pinching off vacuum lines to make sure their not bad too. What's your fuel pressure?

 

Also, check to make sure boost isn't flowing out through the pcv valve.

 

My fuel pressure is at 39 at idle. What is the pcv valve?

 

Pcv sits in a grommet in the rear valve cover, with a hose that goes into the intake manifold.

 

Put a pair of vise grips on that hose, pcv valve hose. I can almost guarantee this is where your loosing boost.

 

I'm not sure what you mean by this, but if you close the pcv hoses then you will have oil vapor pressure coming out of other places (crank or cam seals). The PCV (positive crankcase ventilation) is used to control emissions and get rid of the oil vapor. The government doesnt want the oil vapor in the air so it is recirculated into the engine to burn off in the exhaust.

 

I didnt do anything to the pcv valve but I did retorque all the bolts and retighten the blower belt. It still reads 0 except in 3rd gear it reads 1.2-1.3. Does everyones 3rd gear read higher boost than 1st and 2nd?

 

What I mean is to pinch off the hose to see if that is where his boost is getting lost for troubleshooting purposes. The fix is to make sure the boost isn't getting vented into the crank case through the valve. The valve is hooked up to the manifold pressures, so if it's bad it will allow a reverse flow of pressure from the manifold into the crank case. From what I have been told, this valve should act as a check valve in the reverse direction.