Need Help After FMIC install Boost spikes to 20 psi w. 16G

Quoting turbowop:


Maybe there's a burned valve or hole in a piston? /ubbthreads/images/graemlins/noes.gif



Thats what im affraid of, but he said it starts and idles fine.

 

Wait what dampener??? The Crank Pully??

 

Yes, you might have an intake and an exhaust valve open at the same time and when you turn your engine over you will shut one or the other.

 

[turbowop]

With all the boost leak tests I've ever done, I've never had that happen to me. There would have to be overlap between the intake and exhaust valves for air to escape...or a really shitty ring seal.

I brought up the burned valve or hole in piston because I thought he said it had a really erratic idle.

 

yes the erratic idle only occurred after the fmic install though.

 

The thing that doesn't seem to go along with a massive boost leak is that he says it spikes to 20psi.
20 psi is up there pretty good for a 16g. I can't imagine getting that much boost out of a 16g with any kind of serious leak. /ubbthreads/images/graemlins/dunno.gif

For the boost leak test here's how I do it with my regulator.

Hook things up
Start the compressor - running air into the turbo inlet
Turn up the regulator, keep turning it up until I see the guage un the car go up to desired level.

With only minor boost leaks I had to get the compressor regulator up to 45 psi before my boost guage went to 20 psi

With the noise of the air compressor running and the air running into they system you may not really hear the boost leak. (The bigger the leak the harder to hear)
You will need to use the soapy water to pinpoint any leak - on every joint - clamp - whatever in the system.

Also out of curiosity what does the boost gauge read at idle?

 

when I start the car, the boost guage is in the negatiive zone. WHen the car is in accessory;or off it is at zero

 

[iLLeffeKt vr-4]

Try this when you do a boost leak test. Worked for me every time.

If you do a boost leak test with any piston near top or bottom dead center, you will always have one cylinder where both intake and exhaust valves are open (overlap). Turn the engine to 90 degrees before or after TDC (all pistons halfway down). This will have the intake valves closed in 3 cylinders. The other cylinder will have the intake valves open but the exhaust valves will be closed.

Probably, the easiest way to find 90* ATDC is to remove the top timing belt cover, line up cam sprocket timing marks (by hand, with a 1/2" ratchet in the crankshaft bolt), mark the exhaust cam 6 teeth up from the stock timing mark and mark the intake cam 6 teeth down. Then line up the 2 marks you just made.

Is your FIAC blocked off? If not, with a cold engine, you will have a direct path around your throttle plate along with the ISC & BISS screw. I always test with the throttle plate held open with a piece of wood between the gas pedal and the steering wheel