Unichip boost control help??

BradC

Member
:
03.5 Ti Gray MSP
Hey guys, got a second hand Unichip and installed it today.

So far the Unichip itself is working fine, but I have no boost control.

With the boost switch off, it boosts stock boost.

With the boost switch on, it never cuts boost, if I stay in it, it will boost and boost and boost. Obviously I let off immediately when this happened. (shocked)

I have the boost control solenoid hooked up like so.

Port 1 - open to atmosphere as mentioned elsewhere
Port 2 - Connected to a vacuum line coming from the T by the BPV
Port 3 - Wastegate actuator

When I went to hookup the wastegate actuator, the line popped off, so it has new lines.

The wastegate functions normal when the Unichip isn't controlling boost, so that leads me to the boost controller solenoid.

When it got to me, the plug for the boost control solenoid was damage, so it is hardwired. I tried it wires both ways (only two wires), and had the same effects both ways.

Any ideas guys (besides ditch the UC boost controller)???

Thanks!
 
BradC said:
Hey guys, got a second hand Unichip and installed it today.

So far the Unichip itself is working fine, but I have no boost control.

With the boost switch off, it boosts stock boost.

With the boost switch on, it never cuts boost, if I stay in it, it will boost and boost and boost. Obviously I let off immediately when this happened. (shocked)

I have the boost control solenoid hooked up like so.

Port 1 - open to atmosphere as mentioned elsewhere
Port 2 - Connected to a vacuum line coming from the T by the BPV
Port 3 - Wastegate actuator

When I went to hookup the wastegate actuator, the line popped off, so it has new lines.

The wastegate functions normal when the Unichip isn't controlling boost, so that leads me to the boost controller solenoid.

When it got to me, the plug for the boost control solenoid was damage, so it is hardwired. I tried it wires both ways (only two wires), and had the same effects both ways.

Any ideas guys (besides ditch the UC boost controller)???

Thanks!
Try hooking up the solenoid diffrent ways, I had this problem. I had the vacuum lines up the wrong way.
 
On the rare ocasion I have it on boost it would go to 14spi or so.

You have port 1 open to atmosphere? never heard of that before.
 
Blake said:
when you say boost and boost and boost. Do you mean beyond 13psi?
http://www.mazdas247.com/forum/attachment.php?attachmentid=105370&stc=1&d=1176503993

this is picture Josh from Unichip sent me. Seems like BradC hooked it up right from his description.

I run the high boost setting and mine goes to a maximum of 10psi. exactly where I want it. no higher no less. So I guess I lucked out having it that way. but yeah, it's not supposed to go higher and higher and higher!

I would check your lines again, and if you have problems still, perhaps ditch the boost solenoid and get a Greddy one.
 

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Yeah, its hooked up like Chop's pic.

Boost and boost and boost = my right foot was the boost control. It swung the boost gauge up to 15ish before I stepped off.

According to a thread somewhere on here, Sam and Vic and a few others both said not to worry about hooking up the first port.

Would a Greddy or xyz brand solenoid also require their control unit, or can the unichip control that?

I double and triple checked all the lines. They are all seated fully on their barbs and ziptied on top of that. could the Napa branded vac hose I got be collapsing or something? I wouldnt think so though if it works normal without the boost switch enabled.
 
greddy boost controller comes with it's own solenoid. i saw one up for sale either today or yesterday, go check for sale section.
 
^^^

what they all said.

And i would reccomend against buying used unichips..... its hard to know what the deal with them is.
 
what jmv and everyone else said ^^^

if not, I'd think about sending it to JDMSam to get it re-tuned to your mods. Or Sam can at least tune out the 13psi spike.

(I threw in a pic of my setup)
 

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Thanks for the suggestions so far. Unfortunately, an EBC isn't in the budget for a bit...

Another question. My car always would boost to around 7-7.5ish for a sec, then drop and hold 5.5-6ish to redline.

I put in an SLS catless midpipe, and gained about 1 psi on top of that, but with the same pattern.

With the Unichip in, but its boost control off,...now she spikes to around 10 and holds 7-8ish. Why would it do that?

By the way, this thing definately pulls harder now :)
 
have you ever checked your wga?? That was the cause of my 8.5 spike, 7 hold before i ever had a boost controller on there. Fixed it and it would hold a nice 7, no spike.
 
No, haven't checked it.

How can/do I test a WGA?

Could that cause the uncontrollable boost from the UC???

Thanks
 
alright, do you know where the wastegate actuator is?? Theres a line that comes from the manifold, then it tees off and one goes to the bypass valve the other one goes over to the turbo (at least thats how mine was setup when i got it). Pull of the line that goes over to the turbo, what it actually goes to is the wastegate actuator. If you blow into that line and air goes through, the diaphragm in the wga is bad and should be replaced. Basically it just causes a big vacuum leak. If its working correctly, pretty much no matter how hard you blow no air will go through (i wouldn't try and blow till you're blue in the face, it'll be pretty apparent whether its good or not).
 
jmv said:
alright, do you know where the wastegate actuator is?? Theres a line that comes from the manifold, then it tees off and one goes to the bypass valve the other one goes over to the turbo (at least thats how mine was setup when i got it). Pull of the line that goes over to the turbo, what it actually goes to is the wastegate actuator. If you blow into that line and air goes through, the diaphragm in the wga is bad and should be replaced. Basically it just causes a big vacuum leak. If its working correctly, pretty much no matter how hard you blow no air will go through (i wouldn't try and blow till you're blue in the face, it'll be pretty apparent whether its good or not).
Word, I will give that a try in the AM. Thanks.
 
Alright, this is gay.

Just put in an ATP WGA. With the Unichip boost controller off, it spikes to around 8 and bleeds back to around 5-6.

With the Unichip boost controller on, it spikes to around 13-14 and detonates to hell.

At idle, I pull 18ish in/Hg.

What gives? Boost leak? Vacuum leak? Both??

Any ideas? The only reason it would be bleeding boost now that I have a new WGA is a boost leak, no?
 
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