Rich at idle issues

kalibwenm2

Member +
Hi guys,

I've just had a td04 conversion done, on a stock 4efte with a stock ecu, and my wastegate came with a 10psi spring. I noticed that the car was running a bit rich, from the backfiring when shifting, and a reading of nearly 4bar on my brand new tomei fpr... So i got my wideband installed, and it gives a reading of 11.4 on idle...i haven't driven it yet, to see the afr readings on boost.

What could be the problem there?

My specs are:

-tdo4l turbo
-GFB ex38 external wastegate
-WEPR manifold and downpipe
-acl engine bearings
-tomei fpr plus guage
-aem fuelpump
-Greddy profecB II ebc
-inovate mtxplus afr guage + bosch wideband sensor
-hks ssqv 4
-competition clutch stage 4 kit
 

Jay

Admin
Basically it's fueling for boost whilst standing still which isn't ideal.

There's a number of possible reasons but the increased fuel pressure is a strong contender. Wait until you see how it responds on wide open throttle under load then trim the pressure down as required. Best to start off too rich and dial the fuel out rather than the alternative.
 

kalibwenm2

Member +
Basically it's fueling for boost whilst standing still which isn't ideal.

There's a number of possible reasons but the increased fuel pressure is a strong contender. Wait until you see how it responds on wide open throttle under load then trim the pressure down as required. Best to start off too rich and dial the fuel out rather than the alternative.

Noted, i will give this a try tomorrow. However, i also noticed that my mechanic has removed the stock o2 sensor, and simply placed the wideband in its place...could that be an issue too?
 

Jay

Admin
As in right at the top of the downpipe?

That's a sure fire way of killing it - wide band probes should be placed as per the fitting instructions (about 2/3 feet back from the turbo).

Also the removal of the stock lambda probe will affect fueling too so that could be contributing to your richness as well. Without the stock probe the ECU is running on guesswork.
 

SKINY

Lifer
From what I've seen other GT and Glanzas the fuel pressure is round about 2.5Bar
From memory Ian's was running about that after Jay set it up ?
 

kalibwenm2

Member +
Well damn, i guess i'll just remove the wideband for now, and get the bung welded in soon...i still can't believe he missed out on that part.

But, thanks though Jay, i'll let you know how it goes...cheers brother
 

kalibwenm2

Member +
From what I've seen other GT and Glanzas the fuel pressure is round about 2.5Bar
From memory Ian's was running about that after Jay set it up ?
It's true, it should be at 2.3 to 2.5 for a max boost of 0.6 to 0.8bar, and 2.8 at 1bar boost...but mine just won't go below 3.5bar fuel pressure, no matter how much i turn it down, yet on my knock-off sard fpr, it was all good... Really weird.
 

Jay

Admin
I'd trust the wideband reading before I'd trust anything else but definitely put the probe in the right location. They don't like heat, fuel or vibration so a ringside seat can kill them pretty quick.
 

kalibwenm2

Member +
I'd trust the wideband reading before I'd trust anything else but definitely put the probe in the right location. They don't like heat, fuel or vibration so a ringside seat can kill them pretty quick.

Yes, i will get that fixed soon, i'll be putting the narrowband back in today, and hopefully my mechanic will be free to weld the bung in today or tomorrow.
 

kalibwenm2

Member +
So, i failed to remove the oem o2 sensor from the stock ct9 downpipe (the thing is just stuck there nomatter what), so i will have to order one and wait a fee weeks for it to get here...
But, besides that i managed to fix the fuel issues, it tutns out i was reading the afr wrong, it was actually lean on idle, and super lean on boost, and my fpr was giving false reading due to the 6mm fuel hose from the stock rail to fpr (after i pinched it with a plier, to minimize the internal diametre to try to mimic the 4mm fuel feed line from the filter, the reading finally lowered), therefore i cranked up the fpr and the fueling looks ok for now.
However, i'm still getting boostcut issues in third gear, and it's really savage, it got me thinking i blew up the engine lol, it went up to 23.1psi of boost, yet the wastegate has a 10psi spring, same thing happens when i set the ebc to 10psi max, with 0% dutycycle and 0% gain...How is that possible???
 

kalibwenm2

Member +
Boost leak somewhere maybe, did you try heating the bung on the O2 sensor see if that worked ?

Been looking everywhere, all the piping and vaccum lines a brand new and well tightened, but i will try disconnecting the boostcontroler, connect the ex-wastegate directly to the turbo, and let the other niple vent out.
As for the bung, i gave up lol, tried soaking it in wd40 aswell, but no luck... The prob is that i don't have the proper 02 sensor remover tool, i ended up grinding through the tick cast iron wall around it, so i can fit my open-end wrench, but it still won't come off
 

SKINY

Lifer
Ah you need to heat it buddy, you can pick up wee souffle torches that are more than capable of heating a few nuts for around 15 quids :)
 

kalibwenm2

Member +
It's fixed guys, apparently i wasn't looking hard enough for the boost leak, it turns out both the nipples on the wastegate were loose, and the hose clamp on the turbo outlet aswell...the wastegate is finally opening, and i'm loving the td04 power ... I just need to raise the limiter slightly on the ebc, as the wastegate spring is holding a little more than 10psi (just so my ebc can read the actual boost pressure, which is probably an additional 0.1-0.3psi)
 

SKINY

Lifer
Happy days buddy :)
I was struggling to find a leak on mine for a while, everything was tight, new pipes etc in places. Ended up taking it down to Jay,s and still baffled us until the Legend found my dump valve "gambler pipe lol" had split where it couldn't be seen
 

kalibwenm2

Member +
Yeah, these leak issues can be really tricky to pinpoint, especially if you lack the proper equipment, or just assume that the mechanic did a very nice job in tightening everything...Shit, even my lugnuts loosened up on my way to the vehicle testing station...lol
 
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