OKRX-7

Okay guys, I know there is a few of these posts floating around, I just went through hundreds of posts reading up on them, and basically I didn't find anything truely helpful.

As it says I am seeing a solid 7 psi and it dosen't reach that until at least 3500rpm, drops to 6ish at transistion and jumps right up to 10 psi no problem.

Details, I have a '94 base auto. Mods, this is the kind of fishy part, I bought the car last month so don't flame me for this, I am working on it!

Intake, stock pre-cat (I know) mated to custom muffler shop exhaust with no main cat and a magnaflow exhaust. I have a catless downpipe, a high flow cat and trying to find an exhaust so I can get the damn precat out should have that done within the next week or so. I thought maybe the pre-cat may be clogged but the secondary is making awesome boost and isn't having any tappering problems that I can see.

I did check out...

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

and

http://www.autosportracetech.com/RX-...alBoostPattern

I spent about 6 hours today using both of these, but the information isn't the clearest on somethings, at least to me that is.

Okay here are my results on the boost road test.

1st Step - Do steps in order.

2nd Step - Checked Double Throttle Actuator
No vacuum at operating temp - good.

3rd Step - Check engine vacuum at idle.
Hooked the mityvac up to verify my findings and at the intake nipple I see about 17 inHg.

4th Step - Check no load operation of Primary turbo
Put her in nuetral, WOT hit the 4+psi like the guide says.

5) Check vacuum chamber's storage ability with engine off

* Pull off vacuum hose at Charge Relief Actuator
* Should hear air entering hose vacuum, re-attach hose
* Start engine - briefly accelerate engine to WOT in neutral again
* Turn engine off - KOKO 6 TIMES
* Watch Charge Control Actuator work each time
* Watch Turbo Control Actuator work each time, (need to crawl under the car to see this one)

Now this step through me off some. Is the Charge Relief Actuator and Charge Control Actuator the same thing or different? I tested the Charge Relief Actuator, the rod was pulled in at Idle, I turned the car off and unhooked the hose and the rod came out, so I hooked the mityvac up to it and actuated it a couple of times, as far as I could visually see it was actuating. As far as the Turbo COntrol Actuator, is this the one under the wastegate? I wasn't able to watch it while the car was running but I actuated it also with the mityvac to make sure it was working.

6) Check Pressure Tank's pressure storage ability with engine off
Air left tank, also mityvaced it.

7) Road test with boost gauge
7-6-10



So that is the boost step tests, and as you see, I didn't really get anything from that. As far as I can tell I passed all the test except for the fact I am not hitting 10 with primary.

Some other things I did was check the wastegate (If this is the top of the two actuators) I yanked the line and verified that there is a pill in the line, and then I mityvac'd it a couple times to make sure it was actuating. But if this controls boost on both primary and secondary I don't see it being the problem since the secondary is making proper boost.

I also tried to remove most of the intake pipes and fittings and check for boost leaks. Is it possible I could be dealing with a boost leak that would only let me see 7psi on primary but make 10psi on secondary? I wouldn't think that the problem since I am seeing the exact same boost on the primary everytime.

Any suggestions?

I appreciate you taking the time to read my long post, and I hope I made sense.

Thanks in advance,
Kyle

tiger18

iTrader: (1)

with a boost pattern like that you dam close to what you want sounds like its something small like maybe one of these...
1) Make sure the wastegate rod length is set correctly.

2) maybe the pill in the wastegate line is the wrong size (sometimes a pipe that is old lets to much air past the pill and give a low primary)

3) maybe you have a tiny boost leak in the main system (only small enough to drop pressure on the primary, but both turbos can overcome it).

im not sure what else,,,maybe one of the turbo experts can help.

mad_7tist

check that the ccv is working and is not letting boost go throught the door and out the crv. after 4500 the crv closes and the ccv opens. if the ccv is leaking or not staying closed you will have a boost leak on the primary. find the vac diagram online the ccv and the crv are diff parts of the same system

OKRX-7

One looks like a wastegate the other like a BOV right?

jeffrored92

Sounds like your getting confused between charge relief/charge control.

There is no charge relief actuator - just the charge relief valve. It sits in the 1inch diameter hose coming from the secondary turbo compressor, going to the stock airbox. It vents boost created by pre-spooling the secondary turbo under 4500rpm. The smaller hose connected to the charge relief valve comes from the cahrge relief solenoid.

The charge control actuator sits on the Y-pipe and the rod manipulates the charge control valve, which isolates the primary/secondary turbos. The rod of the charge control actuator should be pulled in at idle. You should see this rod oscillate with KOKO untill your vacuum tank is depleted.

If you're getting 7psi on the primary, 10psi after transition, I'd check the pre-control system very closely. Test the solenoid, check for pills, test the actuator, check the adjustment where the actuator rod connects to the pre-control door, go nuts.

Sounds like your a lot closer to solving your boost problem than I am!

OKRX-7

5) Check vacuum chamber's storage ability with engine off

* Pull off vacuum hose at Charge Relief Actuator
* Should hear air entering hose vacuum, re-attach hose
* Start engine - briefly accelerate engine to WOT in neutral again
* Turn engine off - KOKO 6 TIMES
* Watch Charge Control Actuator work each time
* Watch Turbo Control Actuator work each time, (need to crawl under the car to see this one)

I copied that word for word from the troubleshooting diagram, so thats what threw me off, I saw to many names for one items.


Now my CRV is connected to the manifold extension, and by looking at the vacuum diagram I am assuming it goes stright through it to another line into the solenoid?

racerboy8

My boost is doing the same thing but like 8 - 8 - 10 . Now I just added 3" all the way back, Pettit intake, new radiator with spal fans. Here is what I think, you guys tell me what you think and maybe this will help you OKRX-7. When I added these mods I didn't add the jets in the line like pettit said untill I seen it spike. So when I took the car out it was cooler temps outside and I ran a 10-8-10/12 sometimes spikes to 14 but anyways I figured that would happen. So I need to add the small jet in and I am done. Well this week it was a blazing 96 degrees and I took my car out, the boost while the motor was cold was like 9-8-10 but when it got hotter it was like 7-6-10. I think the intercoller was sucking hot air in causing some heat soak. Also when you take off the airbox what do you do with the lines that have the Charge relief valve in them, just let them hang?

RX7Wishing

^ Dont highjack peoples threads bro... that **** is rude as hell.

scratchjunkie

your boost pattern really sounds like you have a bad coupler(s) and/or clamp(s). did you double check everything?

racerboy8

Hey dipshit maybe it will help him out, maybe he has heat soak.

RX7Wishing

listen KID. You wont get help from anyone on this forum with an attitude like that.


For the sake of this mans problem PM me if you wanna get into a pissing contest with me. ******* noob.


And obviously heatsoak isnt causing his issue since the problem happens all the time.

racerboy8

So your saying that there is no way that he has heat soak?

RX7Wishing

Everyone gets heatsoak. But im saying that heatsoak is not causing his issue. If it was then he would be having no problems at all untill the engine starts to "heatsoak".

OKRX-7

Well I don't think I will boost on a cold motor to see if I see a normal boost pattern.

I test once I hit Op Temp and nothing ever changes, its a constant pattern so something in the system has to be fishy. Its running fine, just wrong. Nothing is erratic or anything. Boost pattern hasn't changed from mid-70's nights to 100+ days.

RX7Wishing

heatsoak is not when the engine is warmed up. Im not saying boost when under NoP.


Heatsoak would be like... sitting on a hot day and letting the engine idle for awhile with no air passing through the rad... And the underhood temps climbing.


So if your experiencing the same problem in 70 deg weather, and 90 deg weather. On the interstate. or from a dead stop... Then it is not a heatsoak related issue. I had the same problem as you and my problem was the WG control and pre control solenoid.

OKRX-7

Okay, going to search on how to test the solenoids. Thanks man.

racerboy8

hey check out were he is from it would happen all the time there! But what ever we will just say you know all and that it must be a leak that he missed or most definetly a loose coupler could cause it. Thanks for your help.

RX7Wishing

lol... ok...


OKR-7, They are pretty easy to test. Robrobinette has a writeup on his site... Let us know what you find out.

racerboy8

Thanks for the explanation, I guess I got off on the wrong foot with the other KID!
btw I wasn't talking about you saying that

99gst_racer

Can you please give a detailed description of your problem and how you fixed it.

OKRX-7

Yeah, I will.

Racerboy, please refrain from posting in this thread for now, we don't want any misinformation until we have tested the chosen course of action.

Thanks.

jeffrored92

Yeah I'm hearin ya. I think they meant carge relief valve in that bit of text. If you check out the diagram at http://www.autosportracetech.com/RX-...BigPicture.htm you'll see there are just 3 actuators, wastegate, precontrol, and turbo control. I assumed that they meant pull the vac line off the charge relief valve, since the charge relief solenoid should provide a vacuum to charge relief valve with the solenoid off (hence also with the engine off). Anyway, just clearing that thing up

I tested my wg and pc solenoids by pulling them out of the car, heating them in an oven, applying pressure to the port that is connected to the wg/pc actuators, and then applying 12V. Unfortunately mine checked out so I'm still looking.

ORX705

i'm having the exact same problem. i have checked everything other then the wastegate and precontrol mechanicals. as the last resort i can only assume the rod lengths need adjusting

OKRX-7

Okay, so I started checking out the flow diagrams and looked into things a bit deeper, and I have to say I have enjoyed researching this since I do environmental systems on aircrafts (F-15's and F-16's) and I am noticing alot of things work in the system much like the aircraft cooling system works as far as using pressure differentials and such to activate systems. And while I haven't checked it out I have a theory whats wrong.

On the bottom you have two actuators (Three, but two side by side) which is your wastegate actuator and your turbo precontrol. Between the two the wastegate doesn't do alot of work until the secondary turbo comes online. Most of the primary boost pressure is based controlled by the turbo precontrol. When I pulled things apart the other day I focused on the wastegate due to my narrow minded experiances with turbo systems (single systems in which the wastegate controls everything).

But that isn't the case for the this kind of setup. So I checked the wastegate line for a pill, and it was there. Which is great since I get good boost on my secondary. But I never thought to check the precontrol line for a pill, at the time I didn't think it would have much to do with the the primary, boy was I wrong. So I will try to check the precontrol line for a pill tomorrow but I may not get to it since I have a two hour drive to my guard base after work tomorrow.

So if it turns out I don't have a pill in that line (Which I am hoping for) then I will move on to the solenoids. I did check the Charge Relief Valve both in and out of the car and as far as I could tell everything was operating properly. So basically I am down to the solenoids or the precontrol.

But I will keep you posted. Hopefully we can finish this off soon and that way future searchers will have a good long in depth post to go by.

OKRX-7

Okay more research basically breaks this problem down to one of three things.

1. Lack of pill on Turbo Pre-control line
2. Bad Turbo Pre-control solenoid
3. Bad Turbo Pre-control Actuator

If anyone wants a breakdown as to why I will post it, but I would prefer to wait till I get all three tested.