G5ALIVE

So two months ago I put on OTTP's solid engine mount (no trans mounts), this is the most recent performance change I have made to the vehicle....
Maybe, two- three weeks after doing so I started to hear a roaring noise, loud rumble when I apply a slight acceleration after coasting.
Usually happens when I try to add a little more throttle to a coasting speed of 60km/h.

I immediately tried putting on the stock motor mount again and the noise was still present. Okay, so i put it back on a day or so later...

I have explored a lot of different ideas: Ive had a tune up, new exhaust header gasket, new fuel injectors, fuel filter, spark plugs, ignition coils, new trans cooler lines, check trans fluid level,
I've had the car inspected for exhaust leaks, tires changed, new alignment, wheel bearings checked,
I am letting my air filter dry as I type this (cleaning it, don't think it will do anything at this point though...)
While going through this, My trans pan started leaking about two weeks ago and the axle seal as-well.
So I had the axle seal re-done and the trans pan re-sealed, fluid filled and level checked.

After that did nothing I kept looking, I removed a nasty throttle body to find oil in my Intake manifold: BINGO!!!! .....not
Anyway, spent a day cleaning my intake manifold (and painting it, why not...), working for a parts department, meh I opted to put in a new throttle body rather than cleaning it.
One thing I have not done yet is cleaned the MAF sensor, though I did pull it last week and It wasn't horrible, didn't really notice any thing bad...

So each time it happens I try to look at my gauges, see what's going on.. IT happens most frequently in high gear, though I have watched it happen in 2nd before.
Air fuel is normal DURING the event, with no misfires either.
It happens usually when the car has been driving for +10minutes,
the car goes through all gears, and does not occur at WOT, only at about my 35% throttle position at 60km/h.
Imagine leaving a Red Light, you accelerate 70% throttle, you go through gears 1-2-3- and your at 60km/h so you let off the gas and star coasting,
now you just want to give her a little more gas, car shifts into fourth and

HHHHHHHHHHHMMMMMMMMMMMMMMMMMRRRRRRRRRRRRGGGGGGGGGG GGGGGGGGG!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!

Let off the throttle and it goes away, shift into neutral it goes away, re apply the the accelerator you will hear it again and again,
The brakes do not feel like they are dragging, I feel a loss of power and hesitation.

Things that have started to catch my attention in the past 2 months,
Engine start up in the morning, Air fuel is spending more time than average getting up to 14.69.
I have had many misfires here and there, not subject to one specific cylinder.
Coming to stop, I'd get misfires consistently. Not Peg-Leg misfires but faltering misfires like a stumble that's caught quickly.
More interesting, I have started to notice AFTER coming to a stop, your at the light for 15 seconds and my air fuel will jump to 16.15 for a split second, then return to 14.69, no misfires are happening at this time,
but I feel it, look at my gauge and boom air fuel 16.14 and just as I'm looking i see it go back to 14.69..

So yesterday, I replaced intake and exhaust VVT solenoids/ actuators. They had some debris on them, for the most part they looked good, but I replaced them anyway seeing the debirs
Getting a LOT less misfires since then! Car seems to be smoother at idle and in drive. But Alas, not the underlining problem.


As I was removing my air intake filter today, that same puddle of ATF was still on the ground from a while back, so I waited, and waited to witness a drop here and there coming down.. HMMMMM
Trans pan is not leaking this time, It honestly could be the same puddle of ATF, and its water dripping down from my subframe from the puddles I went through 10 minutes prior...
Going back out later to put the filter back on and will update If its a leak or just water adding to the ATF puddle....

But I am stumped. I've had three different shops look at it, nobody has been able to determine the noise.

Thinking about trying the solid trans mounts I have, see if that changes things. I Have no consistent DTC and no CEL
Need someone to think outside the box for me,
I'll probably end up bringing it to another shop, sigh,
maybe one dedicated to transmissions, but ultimately don't wanna pay more diagnostic work for someone who's gonna tell me I have a performance exhaust "It's suppose to sound like that"
Because really during a super mild acceleration, the car should not sound like a jet taking off.

ProfDNS

Well, you replaced the TB. It could be possible that the plate is getting "stuck" more open after you open it up after a certain point. I would run a log on an OBD2 device and see if this is true. Should tell you at least what to start looking at while you're cruising around.

G5ALIVE

I got standard HpTuners and only a desktop..... been thinking about this for a while...
Might just have to throw it all in the passenger seat with a booster pack to power it, gonna be a lot of **** in there but I think its my only option.

I believe Aero Force gauges can run logs, never tried though, not sure what kind of data it would collect and how it would read out on the display...

G5ALIVE

So I will look deeper into the throttle body, cleaning the old one now and will test that out

G5ALIVE

Phone died while I was outside so no light to inspect the ATF..

But I got a clean air filter on, swapped back my TB (clean now of course)
Will be watching TB position tmr on my drive and will get back

Sharkey

iTrader: (1)

trying to diagnose this sort of thing over the internet is very tough. maybe if you could get a video of it with clear sound it may help.

one thing i would do is set your scanner up to monitor the tcc on/off command and/or the tcc slip percentage, and even better would be if it has desired tcc slip you can monitor, this is the computers requested tcc slip. basicly what your looking for here is that the actual torque converter clutch slip is close to the desired, this will let you know if the torque converter clutch is slipping excessively.

one of my shops HHRs had a noise similar to what your describing, and the end result was it was caused by torque converter clutch chatter. i was able to see that the tcc clutch slip % was far off of what the commanded slip % was, and that was how i determined that was the problem.

G5ALIVE

Well looking into a laptop to do some data logging.

Watched calculated and desired slip speed rpms today, noticed when the issue is occurring there is zero slip speed rpm. Zero desired and zero delivered.
I would assume that would be the trans is in lock at that moment, which makes sense yes?

Appart from that the two values were very very close throughout my drive.
Got some audio of the noise will get another going home and upload the best ones.

Will be cleaning the MAF sensor, soon.
Got a really bad idle today. IAT temp circuit high, went away after but still I’ll look at it closer
Tried fuel injector cleaner, I run Premium full, and tuned for it.
I’ve reset my tune after installin the solid mounts and again when I did the Throttle body.

Instead of disconnevting the PCM, I will try re- flashing my tune soon.

G5ALIVE

Will also try my stock file (no tune)

see if it maybe I can rule out the tune’s timing and what not