Hey all you TMIC people.

[[HTi]Johnson]

My car stumbles on acceleration at times. I have a wrx IC and I was wondering if having it at stock timing could be doing this. It kinda sounds like it is "post" detonating. I have the timing at 20' btdc(with the green connectors). 1987 GL-10 Turbo with ngk plugs, new wires, new cap and rotor.(that's all I done to the ignition system.) I run only chevron supreme (high grade) 92 octane. THANKS!

[4WDFrenzy]

Do you have the stock BPV on the WRX IC dumping to atmosphere or is it recirculating? If it is just purging the excess boost to the atmosphere, therein lies a possible problem. Vehicles equipped with MAFs are suppoed to have recirculating BPVs(hence the reason that WRXs have recirculation hoses for the stock BPVs.) Purging to atmosphere can cause the car to run rich momentarily when you release the throttle, as the MAF has already metered incoming air and the ECU adds fuel accordingly. When you purge this metered air, the ECU still adds the fuel, but the air that it was supposed to mix with isn't there, thus creating a rich condition. Also, stock WRX BPVs are supposed to leak under idle conditions from what I have read. When the recirculation hose is connected, some air is allowed to bypass the slow spinning compressor wheel(which is now a restriction) and helps to aid in low RPM throttle response. If it is purging to atmosphere, it for one, is drawing in dirty air(unfiltered) and two, the extra air is unmetered.

 

Now to answer your question about the timing, it sounds like it is about right. You shouldn't have anything to worry about in that department. Hope this helps.

 

Patrick

[4WDFrenzy]

Oh yeah, and if you haven't changed the fuel filter, you might change that out. Also, check for vacuum leaks, and also exhaust leaks around the flanges, especially around the turbo mounting flange.

 

Patrick

[Free Range]

Boost gauge? you should show ~20-22 bars of vacume at idle, clean the coolant temp sensor connector, feel all vacume connections for loose fittings, these loved to pop off on mine, especially with the TMIC, Oh and your not just hitting boost cut after four seconds of boost over 9psi, are you, car pulls like mad, then suddenly runs out of fuel, feels nasty. Boost cut can happen with no mods other than a worn out wastegate spring.

 

People are also right on with the recirculating by-pass valve on the WRX TMIC, should be plumbed back into the system, and fuel delivery issues(check plugs for residuals)...

 

Other things to consider are putting all the stock crap back on and seeing if it runs like it used to, checking codes, turning up the fuel pressure, umm yeah, the beauty that is the modded ea82T, let alone that white thang of yours, you still got that custom air ride?

-Nels

[[HTi]Johnson]

Oh hey Nels...

Ok here is my IC set up, I DO have it recirculating.

As for fuel filter, I have replaced it not more than 11k ago, should I again?

 

As for exhaust, it doesn't leak before the turbo...but after the turbo, where my 2.25" downpipe meets the stock mid pipe it leaks...but that's not a factor here.

 

I've checked all my vacuum lines.

 

Not getting any codes...but the weird thing is...I was getting the purge control selinoid code (the wires are busted off of it) but now it's not giving a code. So that makes me think twice about the coolant temp sensor. I need to check it with a multimeter.

I have thought about puttin the stock back on and checking the difference.

 

I don't know what I am pushing with boost...I know I know, I need a boost gauge for the life of me.:-\

 

And another question...when does the waste gate actuate and does it need to since I have a BPV?

 

PS I got rid of the air suspension...well kinda, the compressor and tank are still in the car, but the struts are out...if anyone wants the front pair, they've been modded by someone (they have valves on them so you can pump them up with a tire nozzle), they hold air for weeks. If you want them, PM me.

[Subarian]

The waste gate and the BPV or BOV have different functions. The waste gate limits boost by allowing exhaust gases to bypass the turbine upon reaching a predetermined boost level (about 7.5 PSI on the EA82T). You can increase boost by installing a boost controller that will open the waste gate at higher boost pressure. The bypass valve allows excess boost in the intake to bleed off momentarily when the throttle plate is shut, thereby saving wear on the turbo and theoretically allowing the turbo to spool up faster.