$20 to the one who helps most with this problem.

[DsmDanielson]

I've searched and searched and searched, and Im still stumped on this one. So I recently had issues with my maf and fixed some ground issues (see my other posts) however, my turbo won't boost past 5psi. It has very little shaft play, but no turbine damage but I will be getting a rebuild kit to rule out that possibility. It's a TD05H 20g Turbo. Brand I'm not sure, but looks very sturdy and well made. The car feels like it's retarding timing and is running a bit rich. It also won't run on karman setting, it just starts and immediately dies, especially if I give it gas, however, if I put it on hotwire, I can free rev all the way to redline. I checked the fuel pump, I did a boost leak test. Vacuum is also at -20, it just won't build boost. When I get to about 5 psi, the car bucks and hesitates and misfires, but if I press throttle slowly, it wont hesitate until 4000 rpm, (when my turbo starts building boost again ) The previous owner said it was just fuel cut and needed to be safc tuned but I don't feel like the bucking is fuel cut. I checked my MBC and it doesn't seem to be hooked up properly, and this is really stressing me out. I already swapped plugs and wires. That's why I'm offering reward as I'm stumped at this point. I'll upload some pictures to see if anyone else can see something I don't. It feels like the problems are due to to human error, not mechanical issue, but what do I know I'm new to dsm's. Note: the picture with my hand on a vacuum line, that's hooked to the mbc, and the close-up of a round object with a vacuum line attached to it is where the mbc is hooked to. It's connected to the passenger side under the intake manifold and there's two nipples sticking out of it. Seems to be apart of emissions? Other vacuum line from mbc goes straight to the waste gate that's it. Looks fishy to me.
-Danny

 

[1990dsmkid]

Your boost control appears to be an electrical one? Also it should be hooked up between wastegate and boost source. Normally the line comes from wastegate goes to boost control then to boost source either at j pipe or compressor cover. I also think that last pic is of the egr valve. Should not be going to boost control or bov

 

[DsmDanielson]

Your boost control appears to be an electrical one? Also it should be hooked up between wastegate and boost source. Normally the line comes from wastegate goes to boost control then to boost source either at j pipe or compressor cover. I also think that last pic is of the egr valve. Should not be going to boost control or bov

It's a mbc with a ebc on top of it. You see the prongs to the the ebc but there's a mbc attached to it underneath it's pretty cool actually. I will definitely check the vacuum lines and connect them back to the proper location. So should I get a T-fitting and hook the j-pipe to the actuator as my turbo housing doesn't have a nipple, and route it back to mbc? Where should the second nipple on the mbc run to? Intake manifold?
Edit: Would something this silly be the reason why i can't boost over 5psi? If so, I'll be so mad .

 

[lasershark]

I'm not entirely sure about the ebc coupled with a mbc but this page has the basics of a mbc with some pictures to help.
http://www.dsmtuners.com/threads/best-way-to-install-a-mbc.237982/

 

[DsmDanielson]

I'm not entirely sure about the ebc coupled with a mbc but this page has the basics of a mbc with some pictures to help.
http://www.dsmtuners.com/threads/best-way-to-install-a-mbc.237982/

Thank you for that thread I've never seen it. I noticed in the drawings, there isn't a T-fitting, it's just the actuator to mbc, and then mbc to boost source. When would a T-fitting be used?

 

[DsmDanielson]

I'm not entirely sure about the ebc coupled with a mbc but this page has the basics of a mbc with some pictures to help.
http://www.dsmtuners.com/threads/best-way-to-install-a-mbc.237982/

Thank you for that thread I've never seen it. I noticed in the drawings, there isn't a T-fitting, it's just the actuator to mbc, and then mbc to boost source. When would a T-fitting be used?

 

[1990dsmkid]

There should never be a tee fitting. If your comp cover or j pipe doesnt have a nipple then i recommend installing one ang hook up the lines correctly

 

[PlanZero]

Unless you buy a DSM bone stock most of the time problems can be attributed to human error. What baffles me is that in 2016 when a wealth of information is at your fingertips, people still install aftermarket parts and do mods incorrectly, bad information passed on and on like whisper down the alley.
Hence the reason 90% of the modded dsms on Craigslist list a ton of high end aftermarket parts ("the good") then say you need to tow the car ("the bad") because it's not running.

 

[oneslowwdsm]

I'm so confused. So you have the MBC hooked up to your emissions? How would you expect that to work? Of course that could be your problem. You also don't necessarily need it off the compressor, you could have source off the J-pipe or lower intercooler pipe although may not work as efficient.

 

[DsmDanielson]

I'm so confused. So you have the MBC hooked up to your emissions? How would you expect that to work? Of course that could be your problem. You also don't necessarily need it off the compressor, you could have source off the J-pipe or lower intercooler pipe although may not work as efficient.

No of course I didn't do that. I recently bought the car and as the guy said above it was a car that was already modded but had issues. Now I know what your thinking, why would you buy a car with problems. There's 2 reasons, one being because there's a certain sense of accomplishment when you fix a car from the ground up, and the problems could be very well human error. I already took the mbc line of the egr valve, (silly previous owner) and it seemed to help, still not boosting much though so time for another BLT and I have a turbo rebuild kit on the way.

 

[pauleyman]

So you bought a rebuild kit when you havent even diagnosed the problem yet?

 

[DsmDanielson]

So you bought a rebuild kit when you havent even diagnosed the problem yet?

Well I diagnosed a problem. There's a little bit of in and out shaft play but the turbines are in good shape. Might as well fix it now before it becomes a real problem right? As for why it wont boost, I don't know. I'm thinking waste gate? I'd have to to get the necessary tools to check that. Is the egr a vacuum source or boost source? I'm trying to understand why the PO would hook the mbc to the egr. I believe it's a vacuum source and checking to make sure it's closed all the way and plugging the nipples should help.
EDIT: THERE WAS OIL COMING OUT OF THE JPIPE INLET... It turns out one of the bolts was stripped and wasn't tightening down properly. Talk about a preturbo exhaust leak . I will replace the bolt and gasket to the inlet and see if that fixes the problem.

 

[pauleyman]

Well I diagnosed a problem. There's a little bit of in and out shaft play but the turbines are in good shape. Might as well fix it now before it becomes a real problem right? As for why it wont boost, I don't know. I'm thinking waste gate? I'd have to to get the necessary tools to check that. Is the egr a vacuum source or boost source? I'm trying to understand why the PO would hook the mbc to the egr. I believe it's a vacuum source and checking to make sure it's closed all the way and plugging the nipples should help.
EDIT: THERE WAS OIL COMING OUT OF THE JPIPE INLET... It turns out one of the bolts was stripped and wasn't tightening down properly. Talk about a preturbo exhaust leak . I will replace the bolt and gasket to the inlet and see if that fixes the problem.

That is neither preturbo nor an exhaust leak. It's after turbo and it's a boost leak.

 

[DsmDanielson]

My apologies. I forgot to add that I have an exhaust leak at my flex pipe, (I love speed bumps) but I was confused about it being a pre turbo leak. If it's before the intake inlet it's perturbo then? I guess it makes sense the j-pipe inlet is aft-turbo. I just don't see how, but I'm learning everyday. But if that's a boost leak, it's a big one. And definitely has something to do with the problems I'm having.

 

[pauleyman]

My apologies. I forgot to add that I have an exhaust leak at my flex pipe, (I love speed bumps) but I was confused about it being a pre turbo leak. If it's before the intake inlet it's perturbo then? I guess it makes sense the j-pipe inlet is aft-turbo. I just don't see how, but I'm learning everyday. But if that's a boost leak, it's a big one. And definitely has something to do with the problems I'm having.

Yes it does. Leak test it after you fix that stripped hole. 5 min fix. I also don't understand how people do this. It's not inaccessible or high torque. Careless.

 

[1990TSIAWDTALON]

Pay the man!

 

[DsmDanielson]

Yes it does. Leak test it after you fix that stripped hole. 5 min fix. I also don't understand how people do this. It's not inaccessible or high torque. Careless.

Yeah me neither. That's why I wanted a dsm that had some issues as I know I will take care of it. Dsm's are iconic cars in the performance industry and with good reason, they are just simply fascinating cars, and they need to be taken care of. And yes, it was the advice you and 1990dsmkid that was most helpful, so I have $20 dollars for both of you, just pm me details.

 

[1990dsmkid]

Im not here for the money. Just to help out fellow dsmers. Good luck with the fixes. Post back after with results

 

[pauleyman]

I will decline. Learn. Maintain. Mod
Have fun.

 

[my1st2genGSX]

a lot of what is being discussed I'm having issues with also. But I'm also having a cherry downpipe. I will be looking at all of this as well and the next following days. I am also new to the DSM world. Thanks for all the info as well.

 

[my1st2genGSX]

There should never be a tee fitting. If your comp cover or j pipe doesnt have a nipple then i recommend installing one ang hook up the lines correctly

does anybody have any knowledge on what kind of fitting or what needs to be done to get this done?? My j pipe or comp housing does not have it done.

 

[1990dsmkid]

For j pipe i recommend finding a nipple or same material and having it welded on. As for using the comp cover. The same could be done but i have also brass fittings used on comp covers. Mainly seen them on holsets. Im assuming those ones are just tapped and threaded in. These are the best solutions.

 

[DsmDanielson]

I will post as soon as I get results, thanks for the help fellas.
-Danny

 

[doubleclutch]

does anybody have any knowledge on what kind of fitting or what needs to be done to get this done?? My j pipe or comp housing does not have it done.

SEARCH BAR.

A little work goes a long way. Don't tell me it isn't out there because I just did the same install to my car without having to jack somebody else's thread.

 

[my1st2genGSX]

Do apologize, didn't mean to jack his posting.. I was have some same issues, was just trying to get info also.. Got the fitting fine and now it runs a lot better.