EWG GTX3071 rich at idle

[Bob-o]

SEE POST #7 FOR VIDEO

Hi Guys,

So i've been noticing that my car's been running rich at idle (-20%LTFT), and was wondering if anyone could clear my head with this?

To give some background, I'm running an EWG GTX3071 with supporting mods and a stratified tune.

I did a boost leak test and the only place i could feel/hear air escaping was through the dump tube of the wastegate itself. I'm not sure if this is normal operation, as this would cause metered air to escape through the wastegate, causing a rich at idle scenario. Cruising and WOT fuel trims are fine.

The way I have the EWG setup aligns with grimspeed's instructions: Port 2 to the bottom port of the wastegate, and port 3 to the high pressure boost source. My intake was a custom piece made by PERM, and does not have a intake recirc nipple, so I have port 1 going VTA.

Any thoughts/insight on what's going on?

[sheston]

If it was working fine (I assume it was if tuned by stratified), then look for things that could have changed. ie. Have you cleaned your MAF sensor? Air filter need cleaned? It seems if you're not throwing a code, then it probably isn't a true leak, or a very small one.

If you've changed or modified something, look there. ie. MAF cal, BOV? or BPV?

Will the VTA port let un-metered air in or out?

[Bob-o]

Originally Posted by sheston If it was working fine (I assume it was if tuned by stratified), then look for things that could have changed. ie. Have you cleaned your MAF sensor? Air filter need cleaned? It seems if you're not throwing a code, then it probably isn't a true leak, or a very small one. If you've changed or modified something, look there. ie. MAF cal, BOV? or BPV? Will the VTA port let un-metered air in or out?

MAF sensor and air filter were cleaned last summer, but its worth a shot.

My old EWG was toast and was recently replaced, so i figured it was going to be a loose vacuum line or something, but no dice.

I put my finger over the VTA's port, while looking at LTFT's, and it made no difference, but i supposed AFR's or boost would have been better.

I made some additional findings this evening in that when i'm cruising, or have any pressure on the gas, LTFT's are -4%. If i lift off, they immediately go to -20%, which includes sitting at idle.

I did a lot of searching and some people said purge valve potentially? I'm not sure about that.

When i did the EWG, the DP gasket did look a little tired.. would a turbo > downpipe leak cause negative fuel trims? Or am I out to lunch?

[snailD]

sounds like an exhaust leak, its pretty typical for lean at idle yet no other issues.

I would replace that gasket you said already looked shot and go from there

[Swinger13]

@Bob-o;

What's your MAF voltage bobby?

Also I do have spare MAF sensors if you need to verify if yours is good or bad. If the resistance is poor (higher voltage than normal at idle) then that would cause a rich idle condition

[sheston]

How long did you hold the VTA closed? It takes time to change the LTFTs, you should look at AFR or STFT....

Good luck. Don't pull your hair out, or you'll look like @Swinger13;'s avatar......

[Bob-o]

LOL i'd have to grow a beard of that scale before i could pull half of it out =P

I do have some good news, as well as some bad news.

I was able to confirm with boost leak tester it is a vacuum leak, so i can stop pulling my hair out in that respect.

Bad news is that its coming from the C ring on the back side of the compressor.

Video for visual representation.

What would one do in an instance like this? I tried tightening the bolts, but they didn't budge, and I didn't want to break anything :3

[Swinger13]

Originally Posted by Bob-o LOL i'd have to grow a beard of that scale before i could pull half of it out =P I do have some good news, as well as some bad news. I was able to confirm with boost leak tester it is a vacuum leak, so i can stop pulling my hair out in that respect. Bad news is that its coming from the C ring on the back side of the compressor. Video for visual representation. What would one do in an instance like this? I tried tightening the bolts, but they didn't budge, and I didn't want to break anything :3

That's a spot I've never seen a leak before.

Sent from my LG-D852 using Tapatalk

[sheston]

Search around. I think I remember someone else having that issue. Don't know how they solved it.

Good luck

[Swinger13]

Originally Posted by Bob-o LOL i'd have to grow a beard of that scale before i could pull half of it out =P I do have some good news, as well as some bad news. I was able to confirm with boost leak tester it is a vacuum leak, so i can stop pulling my hair out in that respect. Bad news is that its coming from the C ring on the back side of the compressor. Video for visual representation. What would one do in an instance like this? I tried tightening the bolts, but they didn't budge, and I didn't want to break anything :3

There are o-rings that are supposed to seal where you see that leak but you have to pull off the compressor housing to access them. I think it's just one seal...?

Let me know if you need help @Bob-o;

Sent from my LG-D852 using Tapatalk

[Bob-o]

Originally Posted by Swinger13 There are o-rings that are supposed to seal where you see that leak but you have to pull off the compressor housing to access them. I think it's just one seal...? Let me know if you need help @Bob-o; Sent from my LG-D852 using Tapatalk

You're absolutely correct, and the kicker is that its a $5 o-ring from atp.

Thanks @Swinger13; ! Once i get it on order I'll let you know!!

[Bob-o]

Small update

Phoned ATP and they put me in the right direction for what i'll need to make the repair.

In the rare case this may help someone, here is the part needed

O-ring (Seal), Orange, Goes between Backplate and Comp Housing, T04E Frame GT/GTX : atpturbo.com

New part is due to come this week, hopefully install this weekend =D

[impossible]

Hope everything works out for you man, I had a friend who had a leaking comp housing on his ATP 30r as well

[Bob-o]

Originally Posted by impossible Hope everything works out for you man, I had a friend who had a leaking comp housing on his ATP 30r as well

I think the reason why this happened is that we did have to clock the turbo a little for proper fitment, and in the process did not loosen the comp housing bolts enough. We just got it where it could spin, but did not relive the tension on the o-ring. Spin-spin, o-ring gets pinched or worn, boom. Boost leak

Lol make sure you back those bolts almost all the way out when clocking the turbo!!

[impossible]

Ahh that makes sense

[Bob-o]

This is what the gasket looks like:

Shouts out to ATP for the good customer service on the phone, as well as 1 day shipping to Canada!

I got 2 just to have a spare... this stuff looks like red vines!

[jasper]

If you need an extra set of hands let me know.

[Swinger13]

Originally Posted by Bob-o This is what the gasket looks like: Shouts out to ATP for the good customer service on the phone, as well as 1 day shipping to Canada! I got 2 just to have a spare... this stuff looks like red vines!

Not sure if you installed them yet, but it won't hurt using some moly kote or any o-ring lubricant on the o-ring to prevent it from drying out and future tearing. if you don't clock it ever again though, the only risk of fucking up the o-ring is on installation.

Don't be that guy though...

EDIT: does ATP have a torque spec for those bolts to hold the comp housing?

[Bob-o]

Originally Posted by Swinger13 Not sure if you installed them yet, but it won't hurt using some moly kote or any o-ring lubricant on the o-ring to prevent it from drying out and future tearing. if you don't clock it ever again though, the only risk of fucking up the o-ring is on installation. Don't be that guy though... EDIT: does ATP have a torque spec for those bolts to hold the comp housing?

My plans are going to be marking the way the housing is now with a sharpie, then putting on a new o-ring and sliding (GENTLY) the housing back to its home.

When I called, ATP said the TQ spec is 26lbs on the turbine housing bolts.

I hope I can fill this thread with as much information as I can to help anyone in the future that might be experiencing the issues i had!

[Bob-o]

Can confirm that orange o-ring was leaking

Shoutouts to @jrho; and @Swinger13; for the help!

[Bob-o]

Sadface

Still rich at idle. Checked for boost leaks and heard none. The hunt continues.

MAF sensor perhaps?
Purge valve maybe?
Secondary/Primary o2 sensor failing?

I'm getting like -20% LTFT's, and a CEL almost every time I drive

Chasing these small issues will be the death of this car

[Vansquish]

Originally Posted by Bob-o Sadface Still rich at idle. Checked for boost leaks and heard none. The hunt continues. MAF sensor perhaps? Purge valve maybe? Secondary/Primary o2 sensor failing? I'm getting like -20% LTFT's, and a CEL almost every time I drive Chasing these small issues will be the death of this car

Post a datalog, it may give us some additional clues.

[Cheapspeed]

I had/have the same problem. Justin tuned it down but I never found the problem. I was thinking about replacing the secondary 02 sensor to rule it out.

[Thor Hammer]

Originally Posted by Bob-o Sadface Still rich at idle. Checked for boost leaks and heard none. The hunt continues. MAF sensor perhaps? Purge valve maybe? Secondary/Primary o2 sensor failing? I'm getting like -20% LTFT's, and a CEL almost every time I drive Chasing these small issues will be the death of this car

Does the oil smell of gas more than normal? Pull the dipstick and check.

[Bob-o]

I'll post an idle and WOT datalog this coming weekend.

Would secondary o2 sensor change LTFT's? I thought it just monitored if the primary cat functioned? Or does the primary o2 work with the secondary o2?

Oil doesn't really smell like gas more than normal, granted its been a while ive been chasing this problem. What would that lead towards?

Thanks for the support so far guys

[madspd6]

Blowbye

[Bob-o]

Here are some logs from tonight.

114 is 3rd gear
115 is idle
@Vansquish; @Swinger13;

[Thor Hammer]

Originally Posted by Bob-o I'll post an idle and WOT datalog this coming weekend. Would secondary o2 sensor change LTFT's? I thought it just monitored if the primary cat functioned? Or does the primary o2 work with the secondary o2? Oil doesn't really smell like gas more than normal, granted its been a while ive been chasing this problem. What would that lead towards? Thanks for the support so far guys

Secondary O2 does not do anything for fuel trims.

Its normal for the oil to smell faintly of gas due to blowby. But if it smells strongly it can point to a bad screw seal in the HPFP. When bad it allows gas to travel past the pump piston and into the block. Doesn't sound like your issue though.

[sheston]

Maybe I didn't read back thru the thread enough, but you tried a MAF cal? I would clean your MAF then do a CL and WOT MAF cal and see if that fixed it. Looking at your AFRs across the log and your LTFTs make me think you just need to redo that.'

[Vansquish]

Originally Posted by Bob-o Here are some logs from tonight. 114 is 3rd gear 115 is idle @Vansquish; @Swinger13;

Kind of hard to tell what is going on during your WOT log, as you've got consistent knock during most of your pull.

Your idle LTFTs aren't maxed out, so I'd say that your O2 sensor seems a less than likely culprit as a result. On the other hand, your car is pulling fuel AND running rich at idle (if you're targeting 14.7-ish, that is). That suggests your MAF might be dirty or that you've got air escaping from the system under vacuum (not sure exactly where that'd happen other than the purge valve though).

On the other hand, you are also running pretty rich at WOT, so aside from the knock you're registering I would say that it also appears you might have a boost leak.

[Bob-o]

Originally Posted by sheston Maybe I didn't read back thru the thread enough, but you tried a MAF cal? I would clean your MAF then do a CL and WOT MAF cal and see if that fixed it. Looking at your AFRs across the log and your LTFTs make me think you just need to redo that.'

Well i had the car tuned by Lex a few years ago, and no hardware changes have been made, but I might consider that? Could be a boost leak too seeing as the car ran fine before.

Originally Posted by Vansquish Kind of hard to tell what is going on during your WOT log, as you've got consistent knock during most of your pull. Your idle LTFTs aren't maxed out, so I'd say that your O2 sensor seems a less than likely culprit as a result. On the other hand, your car is pulling fuel AND running rich at idle (if you're targeting 14.7-ish, that is). That suggests your MAF might be dirty or that you've got air escaping from the system under vacuum (not sure exactly where that'd happen other than the purge valve though). On the other hand, you are also running pretty rich at WOT, so aside from the knock you're registering I would say that it also appears you might have a boost leak.

Thanks Vansquish; Perhaps i'll have to go back and do another boost leak test and really listen to see if I missed anything

I appreciate the help lads, I just wanna get my car to run right D:

If boost leak test and cleaning the MAF checks out, perhaps I'll look into purge valve.

Also, I was just curious and looked at AFR's while the car was idling. If i wiggle the MAF harness, AFR's change and get richer. Coincidence?

[802MS3]

Got any random plugs missing from your IC piping? A plug on my HTP under-route hot-pipe decided to eject itself after a couple hundred miles of installing it. It was the optional boost source bung right after the compressor exit. Symptom was extremely rich trims in all situations. Never lean, which I was surprised about.

I wouldn't try to tune the MAF around it. You most definitely have a leak somewhere is my guess.

[Bob-o]

I also remembered that my intake does not have a recirc nipple, so one of the ports on my EBSC is VTA. Would that cause the rich at idle/under boost? Or is it more complex?

[Thor Hammer]

Originally Posted by Bob-o Perhaps i'll have to go back and do another boost leak test and really listen to see if I missed anything Also, I was just curious and looked at AFR's while the car was idling. If i wiggle the MAF harness, AFR's change and get richer. Coincidence?

Just listening for boost leaks wont cut it. Get a bottle of soapy water and spray every connection point. Bubbles will form if there is a leak.

What do you have for a BPV? Check that. My synapse was leaking at the discharge o-ring. Would have never known without soapy water.

If you see changes when wiggling wires the integrity of the connector is compromised. I would replace it with a new one and splice it in or try and repair yours. Do a search on it as its been discussed and solved quite a few times here. Good luck!

[Swinger13]

Originally Posted by Bob-o Here are some logs from tonight. 114 is 3rd gear 115 is idle @Vansquish; @Swinger13;

so boost leak test with soapy water or something bubbly is best. Try that, although we've checked this before and that might be beating a dead horse there. @Bob-o; use your discretion there...

MAF looks fine. I'm thinking one of three things here.

1. Spark plug gap is enlarged and needs to be re-gapped or replaced
2. A hidden boost leak
3. A faulty wideband o2 sensor

[Thor Hammer]

Understanding Fuel Trims & Using Them To Detect Leaks

[Bob-o]

Originally Posted by Thor Hammer Just listening for boost leaks wont cut it. Get a bottle of soapy water and spray every connection point. Bubbles will form if there is a leak. What do you have for a BPV? Check that. My synapse was leaking at the discharge o-ring. Would have never known without soapy water. If you see changes when wiggling wires the integrity of the connector is compromised. I would replace it with a new one and splice it in or try and repair yours. Do a search on it as its been discussed and solved quite a few times here. Good luck!

I am going to investigate the MAF issue further and see if this behaviour continues. If that is the case, I will look into trying to repair the wiring.

Originally Posted by Swinger13 so boost leak test with soapy water or something bubbly is best. Try that, although we've checked this before and that might be beating a dead horse there. @Bob-o; use your discretion there... MAF looks fine. I'm thinking one of three things here. 1. Spark plug gap is enlarged and needs to be re-gapped or replaced 2. A hidden boost leak 3. A faulty wideband o2 sensor

I'll take some time to check the plugs, and perhaps do another (for the 100th time) boost leak test.

Wideband o2 is a possibility; would not know unless i swapped mine out with a known working one.


Thanks for all the help and insight everyone D:

Something else I can add is after I replaced the orange o-ring on the turbo, my LTFT's and cold starts were solid. Went up to 2000 RPM, and stayed there until it slowly dropped down.

Nowadays upon cold start the car starts up a little rough, and has a hard time holding a certain RPM, and sounds like its misfiring almost until it warms up.

[Thor Hammer]

I bet once you fix your MAF issue things may get a whole lot better.

And I never heard of an O2 sensor working intermittently. It either works or it doesn't. I could be wrong.....

[Bob-o]

Jacked up AFR's / Trims lately

This really leads me to think it could be the MAF sensor wiring.

My car is a 2009 too

[Bob-o]

January Update:
So the car's been sleeping all winter, and I got some random spur of motivation to give it another go.

To keep everyone up to date:
Car was running rich (LTFT's in the -18-20s)
Turbo gasket was leaking (repaired)
Suspected MAF ground wire issue (new wire changed in)
Still running rich

I've run multiple boost leak tests, and came up with nothing quantitative, which led me to lean towards potential injector seals?

I had done CP-e seals a few years back, but that was in the dead of winter, and I was not aware at the time that CP-e recommends you put a sealant between the injector and seal, as well as the seal and the head.

To test, we ran a compression test, and sure enough, cylinder 3 was a bit lower than the other.

***We only idled the car for maybe 10 minutes to get it somewhat up to temp, which is why the numbers sound a bit low, but consistency across the board is more what we were interested in

Results came in as (Cylinder 1-4):
160-159-147-160

So cylinder 3 seems a bit down.

The initial cold start was quite rough (coughing, lumpy idle), granted it is on the same fuel from 4 months ago, and it's just been sitting in the garage all winter.

Drivability issues follow as:
Rich at idle (CEL sometimes present)
KR at WOT (log above)
Fuel trims very negative

I will also note that the spark plug/spark plug hole for cylinder #3 reeked like fuel, and the plug was distinctively more 'wet' than the others.

I wonder if the cyl #3 seal let go, or if there's any other directions we could take into consideration?