Ok I know there are a million threads out there, but I have searched and couldnt find anything helpfull.

Ok I put in a new motor over Christmas holiday. I didnt have a boost gauge before the rebuild so I dont know if my issues were present prior to the rebuild. Anyway I didnt a vac. house job while I had everything taken apart.
Well I get eveything back togather and get a boost gauge and Im getting about 5psi-7psi. Well now not only does it boost low but when It hit the transistion point from primary to secondary it shutters. This is a new problem that started last week. Then around 6k it stops, and is solid till redline. Pattern was 5-5-6 and with the shuttering its 6(or 7)-6(or 7)- shutter 5. Ill get a better ready on it tommrow to tell u exactly what it is.

Ive checked all 1" piping for leaks and I have none. Ive replaced the soleniod that sits under the UIM. Its the one that doesnt sit in on the rack. I just tested the 2 right under the UIM that sit right next to each other. Put a charge to them and the let air blow through. I have the pills in the correct places. No tears that I can see in any piping or vac. lines. Check valves are ok, vac. tank is ok, and the pressure tank is ok.

Is there anything that could cause these problems. What about the acuators themselves being messed up? and not a soliniod that controls them. How likely is it the turbos themselves? I would hate to buy a new setup and it still not work.

I guess I need to pressure test the CRV and see if it will hold pressure. The BOV is ok cause I switched it out with a friends and still the same.

mods are:
K&Ns with hard intake pipes
PFS purple computer
street ported motor
RB carback
downpipe

 

I wouldn't bother testing the CRV just yet. Basically the CRV is venting the secondary pre-spool (so it doesn't over-spool while it's not in use). If you aren't getting full primary boost, the CRV isn't the problem.

I would start by checking the wastegate actuator. Check this site on some tests that you can do to verify that it's working properly:

http://www.autosportracetech.com/RX-...leshooting.htm

Also, make sure you don't have any cracks or tears in the IC piping and couplers.

 

also check that the electrical connectors for the wastegate and prespool actuators are plugged in correctly. try swapping them and take it for a test run.

that wound up being the issue with one of my boost problems where i wasn't making more than 7 or so psi.
it looked like the plugs were correctly labeled but they were not. i credit my buddy ccarlisi with the fix

 

Ive tried most of everything on that site Mahjik, but i do have a question about the wastegate. Which way is closed on that actuator? pulling it towards the front of the car or towards the back of the car?


and about those two soleniods and plugs. Ive tried switching the plugs around before and nothing happened. Ill try again but i dont think it will fix it.

Thanks for the replys so far

 

bump I really need some more help on this.

 

i have a very similar problem with low boost. i have recently started looking at the turbo control actuator and its associated solenoids and vacuum lines. though i havn't fixed it yet, i think i may be onto something.

here's yet another test you should try

TCA testing:
1. Pull off strut brace and pressure chamber (can leave hoses attatched)
2. You should see four 4mm metal hard hoses that come up. Two of them go to the solenoids mounted on the front of the UIM, forget them (wastegate and turbo pre-control solenoids). The other pair should have rubber hoses that connect them to the rat's nest. You need to tee into these.
3. One at a time tee into the hoses and connect a boost gauge. The pressure side (forward hose IIRC) should sit at zero until you go past 4500. Then it should kick over to 10psi. The vacuum should kick over to at least 15mmHg.

 

what about the charge control actuator? could it cause this?

Ok i did a boost test and my boost is back down to a 5-5-6 but with the shutter it goes 5-5-shuttering-3. But here is something I think my point to my problem if someone knows what is going on.

If I rev up slowly to about 4500rpm I will get almost full boost.

So any more thought. I think its going to be an actuator or somthing that controls them, but I need help on seeing which one it is.

 

BUMP

 

If you aren't getting full primary or secondary, it's most likely a problem with the IC piping/couplers and/or the wastegate.

A problem with either of those will limit both primary and secondary boost.

Also, did you check the boost pills especially the one in the wastegate line?

 

yes i have looked at the pills a couple of times to make sure they were in the lines correctly.

Well I cant check anything for a couple of days now cause I just had all 4 wisdom teeth cut out this morning, but more help/advice is welcome.

 

bump