So I'm having some issues with my vehicle not being able to build any boost past 3ish to 7 and some change psi. The car is a 2000 Integra with a b16a2 turbo.

My tuner has absolutely been no help so far so hopefully you guys can help out a bit. When I am driving the car I am unable to build boost past 3/7psi it seems like it hits a boost cut. The car is on boost by gear: 1st is gate, second should be around 13/14 I believe, and 3rd and up is like right around 20. The car has a new distributor on it (an obd1) cheap mostplus with the wire harness conversion to obd2. 7e plugs on e54 gapped to .19.
At first I thought it was an issue with spark blowing out but no longer believe that to be the case. Currently, my cluster rpm gauge doesn't work due to the distributor I currently have (I would like to get an obd2 one so if anyone has any suggestions where to get it please let me know also car makes 446whp) and my speedo is also not working. At one point while driving the car it gave me a VTech solenoid circuit high voltage code. I have a single wire running to my vtech solenoid straight to the ecu. i saw that it had become pinched so I freed the wire and the code went away. well, I got the code again and thought that this could be why I wasn't building any boost so I pulled the solenoid checked to make sure it was clean it was and the plunger operating properly put it back code went came back. so what I did was went into Smanager and turned off vtech thinking this would help solve the issue seeing as boost and that come in around the relatively same time. well, that didn't help. I pulled the mac valve and checked it on the battery and it pulsed so I believe that is in working order. I'm a bit lost here am I needing to get it retuned I couldn't expect that to be the issue out of nowhere. so now I'm going to check all the vac lines concerning the mac valve and wastegate to make sure they are clear and not clogged. any pointers or next steps would be greatly appreciated. I'll attach some pics so you can see how the vacuum lines are hooked up. It won't let me upload the datalog for some reason, but if anyone wants to see it I can email it.






thanks in advance it'd be great to finally drive this car the way I've wanted to lol

 

I think you are just blowing the gate open with exhaust pressure. What spring is installed?

I believe you need a 4 port boost controller to really get control. You can the. Feed boost pressure to the top of the gate to help hold it shut when running a light spring.

 

It’s a 10 psi spring. My wife has been suggesting to try a heavier spring. Do you think that will help?

I’ve never had that kind of boost controller in this one and it’s worked before

 

Can't hurt anything trying a heavier spring.

 

I just changed it and hooked it up how the hondata instructions said. So we’ll see if that works

 

I connected everything like this and I wasn’t able to build anything last like 4-5 lbs. I also tried it without the compressor housing and it still didn’t work.

 

Turbo damage?

 

No, it’s a new turbo

 

What do you get for boost without the boost controller? Just wastegate to compressor.

 

I may have hooked it up wrong. Which part of the wastegate is supposed to go to the compressor? I did it with no vacuum lines going to it and got like three lbs. Do I go from the top or the side of the wastegate?

 

Side.

If you only got 3psi with no hoses connected then you might have forgotten the valve seat for the wastegate. It goes between the manifold and wastegate. Little stainless ring about the size of your wastegate port.

 

The valve seat is definitely on there

 

Boost leak would be the other option.

 

Since you messed with your file how did you upload the changes? Did you download them off the s300 or upload?

 

I think OP has a hardware problem at this point. Not related to the software.

 

I’m almost certain it’s not a boost leak. Although maybe I didn’t hook up the vac lines correctly when I put on the new skunk2 ultra manifold.

im at work right now but I’ll go through the whole system when I get home and check.

if it’s not a boost leak what else could it be?

 

Massive exhaust leak. Your blow off valve looks a little suspect. Might be sticking.

That is kind if it.

Was the turbo known to be good? It previously made 20psi on your specific build? You change anything on the intake side of the turbo? A new filter? Make sure the intake on the turbo is free of obstruction. Maybe it tried to eat the air filter?

 

I thought of the blow off valve too, but it’s functioning properly and not sticking. The turbo is known to function properly, and I did get a new intake manifold. Also, that’s a turbo guard, not a filter so there’s not an issue with suction

I really appreciate the time you’re taking to help me troubleshoot! Thank you so much

 

Answer my question

 

I missed this, sorry. I uploaded it to the ecu

 

How does the engine feel at whatever boost it makes? Is it pulling cleanly to the rev limit? Or does it miss and stumble and fall on it's face? Are you able to monitor air fuel ratio? What do the logs look like? Correct fuel ratio? Or is it going lean when it is not making the boost it should?

Do you have more than one boost reference? Are you just looking at the map in the datalogs or do you also have a boost gauge? Do the numbers match?

 

So when I drive the car it feels fine n pulling "good" when it starts to build boost then it doesn't necessarily fall on its face but it really seems like a boost cut. So i re-checked the i/c piping no rips and it's all on and tight. I tried to run a vac line from the turbo compressor housing to the side (bottom) port of the wastegate (i put a slightly heavier spring in it last night) i went from roughly 10 to roughly 13 and took the car for a spin about 10 min ago and it hit 3psi in 2nd gear and 5 psi in 3rd. the ebc is not hooked up its just sitting there the vac lines for the bov and going to the intake manifold are all hooked up with the one that would have gone to the mac valve being plugged. So i believe my tuner originally used the wastegate for a boost reference it was set up originally how the pictures up top showed. the biggest difference from when it was running correctly is I put that skunk 2 intake manifold on. but I don't believe it to be a boost leak seeing as the wategate wouldn't even reach gate pressure? car is also still on the boost by gear tune. I don't know if that would have something to do with it. but I had also tried a different tune and that one also did not work. the afr seems to be in line with what it should be I wasn't able to load a data log on here Idk why my wife tried to help lol most I can do is email them if someone is curious. I also wanted to say thank you for the help thus far I really do appreciate it.

 

It really doesn't sound sound like a tune issue. Still no boost with the solenoid unplugged and boost by gear acts only on the solenoid.

Does the turbo sound correct? What RPM do you start seeing boost?

 

The turbo sounds fine- no weird noises or anything. I hooked up the wastegate to the turbo compressor housing to the side of the wastegate with the top port VTA. I start to see boost probably around 3000 rpm and then there’s a cut around 4-5000. It usually builds to around 5-7 psi but yesterday I got 3 psi in 2nd gear and then 5 psi in 3rd, but then 0 when I went back to second

 

And to be clear that is at wide open throttle and a good load?

Top of 3rd middle of 4th at wide open you only find 3psi?