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Since this is another problem i thought ide make a new thread, Thanks to all those who replied in the catch can thread, I now have another problem, It was there before the catch can install as well.. This is the first proper time im getting this Rb25 running in my silvia and so far it doesnt seem to be boosting at all, Before i done the catch can / pcv block off it used to read vaccum, now its not even reading vaccum or boost, is this possible, will test another guage but its defiantly not boosting either way.

it also doesnt idle, it needs a fair bit of rev to stay alive but im assuming its because its un-tuned? im running a z32 afm and 550cc injectors, ive changed the latency to the % listed in a thread i found on here somewhere, and pretty sure i wired up the z32 correctly, and ive selected the z32 afm in the PFC.

things to note :

relocated AFM to just before t/b -

Blocked off PCV valve -

Not running a boost controller ( have 18 psi spring in wastegate ) so have waste gate going directly to compressor side of turbo

i have 2 photos if anyone spots something that isnt right please let me know.. Also a video of the car stalling

since the video ive installed the radiator and fan, put on the catch can, put a pod on the turbo, replace the fuel lines, and thats about it...

post-16967-0-86353100-1380228592_thumb.jpg

post-16967-0-98369100-1380228610_thumb.jpg

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I didn't read your other thread but did you program the PFC for your injectors? It would probably run with the 550's but I can't imagine it would idle well or at all.

If you're unsure about the afm wiring you can test most of it pretty easily with a DMM

Ok i have fixed vaccumm isuue , the gauge was dead so i put a new one and now reads vaccumm , still no boost though or idle though....

Unplugging tps changes nothing -

Changine % values in pfc for injectors doesnt do anything either, have tried from 50% to 100% in 10% incriments and it doesnt help or even change thd way the engine runs ..

You are on your own sorting this one out, placing the afm directly in front of the throttle body brings all sorts of issues into it. Either tow it to a tuner and hope they can sort it out, or go back to a stock design imo.

Yes, because it is daft. The idle valve is now drawing unmetered air. Stop and think about the flow paths of the standard setup, then compare with the air flow path of your setup. Then slap yourself on the forehead and revert it back to the way it should be.

You CAN have the AFM after the turbo. But you CANNOT just move it there without tuning for it. The AFM is "calibrated" (to use a slightly inaccurate word...more like the ECU has a calibration in it for the AFM) in the standard location, attached to an airbox, upstream the turbo. Put it somewhere else (even just putting a pod filter on it) and the calibration changes. A pod won't cause a big change. But putting it in the post turbo pipework certainly does. And putting it right in front of the TB is the WORST place you can put it.

Yes, because it is daft. The idle valve is now drawing unmetered air. Stop and think about the flow paths of the standard setup, then compare with the air flow path of your setup. Then slap yourself on the forehead and revert it back to the way it should be.

You CAN have the AFM after the turbo. But you CANNOT just move it there without tuning for it. The AFM is "calibrated" (to use a slightly inaccurate word...more like the ECU has a calibration in it for the AFM) in the standard location, attached to an airbox, upstream the turbo. Put it somewhere else (even just putting a pod filter on it) and the calibration changes. A pod won't cause a big change. But putting it in the post turbo pipework certainly does. And putting it right in front of the TB is the WORST place you can put it.

This is exactly the advise you should listen to, especially the highlighted statement. This will be the idle issue for sure.

As for the not boosting thing, I'd take it to a tuner and see if the tune is the problem or if he can find any issues

Thanks for the replies guys! i have put the afm back to just infront of the turbo instead of the T/B and it runs fine now, idles beautifully, untill it warms up then it hunts and runs a tad rough, but it does idle so im happy... I didn't realize moving the afm around would make such a big difference, i guess ill just get the tuner to relocate it when its ready for tuning.

Thanks again.

  • 3 months later...

http://m.ebay.com/itm?itemId=261342047568

Giving this a quick bump, I'm still having a boost issue and wanted to fix it before it goes in for a tune in 6 days as its booked in for a tune only and not anything else, I've set the wastegate ( external ) like shown in the link above , solenoid has 3 ports , port on the left goes to bottom of wastegate , port in middle untouched and port on the right goes to top of wastegate and t-pieced into cold side of turbo....

Does this sound right ? Could having No tune be causing it not to boost ? Specs are ffp, 550cc injectors , z32 afm and td07 turbo

Link goes nowhere. Think because it looks like a mobile link

Capture-6.png

Mine is setup like this and the port from the wastegate is the normally open port (If you blow through that port on the solenoid it should come out the middle port)

This is how the Link ECU/Solenoid works anyway, so that if the solenoid fails its in a failsafe position that will allow the wastegate to open (at spring pressure)

Hi thanks for the reply man, I posted link from mobile maybe that's why it doesn't work but the instructions on my hdi boost controller have the ports going the other way around compared to yours ? Might try switch them around then and see what happens ?

Ok i switched the lines around and now ive got it to hit boost in neutral ( yes it takes alot of revs ) but im a little scared to try and drive it and see if it works properly under load, i dunno why but after messing with the inj on the powerfc i can get the afr good on idle but then after it warms up and after giving it a bit of revvs it starts to run like crap again, also has alot of smoke but might be because i have side pipes or running rich under revs ....I have a datalogit and copilot but im a little scared to play with that stuff, might leave the rest to the tuner....

Well when i had the lines the other way around it wouldn't even hit 1psi, But this time after switching the lines around and letting it idle and warm up for a bit i gave it a nice rev and it climbed well above, i couldent see exactly how much but im guessing its working now because its actually boosting.

Bit late to the party but mine is setup the say way you described in your first post, you need to have it tuned to work with the AFM in that position. I can guarantee the way you have the AFM setup in that pic will give you boost leaks, you have chop it up and install into an ally or steel pipe.

Also the oil feed on the turbo should be vertical if possible. Coil packs look stock too? If they are the originals then you will need new ones or you wont make it past 10psi without a miss. Your gonna max out those 555cc injectors pretty quickly too, < 300kw.

Edited by battery

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