boost ??

[2fst4u]

I have a 90 laser RS turbo 14b, 255lph, safc1, removed b-shaft, and boost controler. I am curently running 14psi. everything was working fine(spooled up to 14psi around 4000rpm to red line) but now I am having a problem with staying at 14psi.if I get on the gas the car reaches max boost at 4000 then at about 5000 drops to 10psi and trys to go back to 14?? why is it going to 14psi then droping to 10psi and then try to spool up again to 14???any ideas

[carltalon]

Check for boost leaks. 4000 rpm's seems a little late to me my scm-61 makes almost 20 psi by 4000.

[1ViciousGSX]

Boost leak or BOV opening?

[TheBlizzard]

Enough. Check for boost leaks first and then post results and we will go from there.

[joesushi]

Do you have the boost leak tester kit? It consists of a quiet well lit garage, rubber cap with bike valve on the end to go over compressor inlet, A squirt bottle with soapy water, and a compressor with the air valve fitting to pressurize the system. Works all the time. If you need help building one, berda and i made one in about 30 min. Fleet farm, napa, and home depot will have all you need.

A 4 inch long piece of 2.5" O.D. (outside diameter) hose. (I used some radiator hose I got at NAPA)
1.5" I.D. (inside diameter) PVC end cap.
2 band clamps that will fit around the 2.5" pipe above.
A valve stem (I used the rubber type you press in)

With this you can get a rough idea on what you need. I would recommend using the valve stems that bolt in, they dont leak for sure. Eliminate one leak at a time.

On the same topic, I did a test on our galant vr4, I found 4 major leaks in the first 5 minutes. It's really worth it. The last major leak i cant fix is a leak by the isc motor, Its a massive leak and i cant build up more than 6 psi, it just whistles and howls loudly, and when i spray the soapy water down there instantaneously huge bubbles appear. This is on the throttle body. Any ideas?

[tsigurl1991_rx]

Yes there are many reason's why it could be doing that. My egal talon TSI did the same thing exccept at 17psi and then to 12psi and it ended up being a boost leake. Listen to the guys they know what there talking about.

[Thor06]

Boost spike doesnt have anything to do with boost leaks does it?

Thanks for the boost leak tester instructions, I am going to go make one in about a half hour and see if thats maybe why my buddies car isnt starting.

[TheBlizzard]

No. If you have boost spikes it will jump up high and then settle down right after boost comes on. Boost creep is went the boost climbs the higher the RPMs go (usually because of small wastegates and to free flowing of exhaust).

A boost leak would probably not make the car not start. Unless you have a intercooler pipe totally off it should start. It will most like even run with a intercooler pipe off, it just wouldn't go anywhere if you were using a stock MAF.

Either way a boost leak check is a bad idea but I think the starting issue you speak of is something else entirely.

[2fst4u]

I just go back in town....and I did check for boost leaks and found none! their was no boost leaks at all...So I drove my car for about another 500mile and now blue smoke is pouring out the exhaust and my turbo is fried:-( o well time for a 16g

[98gstaherns]

Hey mines going too! lol it sucks!