4G63 Turbo bogging down under boost

[poppabear]

i actually have 2 questions.

1. For some reason if i was driving and decided to tip in to the throttle heavy, once it hits high boost it wants to bogg down. almost as if it was choking out, getting to much air or possible boost leak ? i have no CEL on and this is a stock 4G63 Turbo engine. What are some area's i can check to narrow it down ? If i give it gas slowly it will move just fine, but while in higher boost and heavier throttle it wants to sputter/spit/bog/choke, which ever word you like to use to describe it.

2. At 80 mph in 5th gear the car runs @ about 3,600 RPM's ... is this about right ? If not what should i be running @ and what are some possible reasons behind the high RPM's ?


Thanks for the help.

Remember, this vehicle is a completely stock 4G63 AWD Turbo
95 Eagle Talon Tsi

Thanks,
Mike

 

[rush2252]

When you say bogging what exactly does the car do? The stock setup on a 2g doesnt allow for much power over 60mph and lacks power over 5k. This is due to the fast spooling small t25.

And to the other posters. The 2gs run 8psi!!! I just hooked up an aftermarket gauge before my swap and test the WGA @8-9psi.

I believe if your boost leaks are fixed and you replace the 1gBOV it might help. The BOV can be used but If you dont want to do any major mods buy the flange adapter for the 2g cars. If not your going to have to fab stuff this involves cutting the stock 2g upper IC piping.

Kolby

 

[poppabear]

When you say bogging what exactly does the car do? The stock setup on a 2g doesnt allow for much power over 60mph and lacks power over 5k. This is due to the fast spooling small t25.

And to the other posters. The 2gs run 8psi!!! I just hooked up an aftermarket gauge before my swap and test the WGA @8-9psi.

I believe if your boost leaks are fixed and you replace the 1gBOV it might help. The BOV can be used but If you dont want to do any major mods buy the flange adapter for the 2g cars. If not your going to have to fab stuff this involves cutting the stock 2g upper IC piping.

Kolby

Basically, bogging down, sputters, whatever ....
this only happens under heavy accel .. sometimes not even under WOT.
When it happens its *NOT* like the RPMs drops and the car wants to die, the car just sits there and sputters and i have no pull what so ever. it doesn't even really buck at all either, you can just hear it, best way to describe it is that the intake is choking.

1st gear i get a small buck at about 3500 - 4000 RPMs but then continues on
2nd gear it gets worst @ 3500 - 4500, under heavy throttle just sits there and sputters, let off a little and she takes off.
3rd gear - same as 2nd gear
4th gear gets a little better
5th gear little better than even forth gear.

^ not sure if this info helps you or not. i never loose RPMs or Boost, seems to stay right where it was when it started sputtering ...

Alot of time people believe that the word bogging down means the car almost dies ... never has this happened to me ... its just sputtering and has no power under the heavier throttle and higher boost levels

Thanks for the feedback on the BOV, i will just get the adapter, any rec's on where to get the adapter ?

Thanks,
Mike

 

[poppabear]

Just giving it a little bump, anyone have any feedback for me ?

Thanks,
Mike

 

[rush2252]

Okay sorry future reference dont "bump" it the mods will complain

It sounds like its starving for fuel or possibly a catalytic converter plugging up. Two ways to check. Unbolt the exhaust from the o2 housing and take it for a "loud" quick spin. Or pull the exhaust and examine the cat you should be able to see through the honeycomb catalyst. Then check fuel pressure. There should be a post somewhere on the steps for check fuel pressure on a 2g. Its a little timely but it could be your issue.

Heres the brief DIY fuel press test. Remove backseat lower cushion. Unplug fuel pump unit located on passenger side.

Out under the hood there should be a brown test connector. It should be a single wire with a plastic cap behind the throttle body. Remove the cap.

Unhook the fuel line and drain excess fuel out. Install FP gauge. Reinstall line. The turbo models dont have a shraeder valve for easy access you will have to tap into the feed line on the driver side.

Run a jumper wire from the + post on the battery to the test connector. This will engage the pump.

Start the car.

You should have 27psi (vacuum line off of FPR UNREGULATED) at curb idle with no accessories running
You should have 43-45 psi @ curb idle with vacuum line connected (regulated)

Those are the steps from the top of my head the way ALLDATA and "thebook" recommends there are other ways but if you have ever worked on cars you get the idea. The reason for the jumper wire is to get a good 12v constant feed to the pump w out traveling through the MPI relay etc.


(I might have those backwards on the pressures its been awhile)


A bad pump or FP regulator could be the culprit if its a fuel issue. And NO they dont always throw a CEL if its either of the two listed. Initially I assumed you were just experiencing the doggy stock 2g but it sounds as if the car is falling on its face under WOT.

The only thing that can cause that would be lack of fuel ignition loss or its choking due to plugged cat becuse you've ruled out the BLT.

Good Luck
Kolby

 

[McDeezy]

Was this problem ever resolved? my 2g is doing the same thing and im still trying to figure out what it is.

 

[shockracer]

sounded like to me that it was cutting timing, mine does it off and on. first it will start pulling good then cut back on the power, i don't lose any RPM's but just rev's much much slow. IDK just a sugesstion.

 

[McDeezy]

Mine goes up to 4 1/2k and starts sputtering nasty.. It doesn't drop boost, but it won't accelerate after that. I have changed my spark plugs, spark plug wires, fuel filter, air filter and still nothing. I took it to a shop and the guy said he will hook it up to a wideband but its $80 an hour and he wants it for a full 24 hours, but im super broke. Any ideas?

 

[michaellago]

POSSIBLE PROBLEMS
-spark plug
-spark plug wire
-coil pack
-fuel injector
-boost leak
-crankshaft position sensor (faulting. once completely out your car will die and/or not start)

 

[shockracer]

hard to say $80 is kinda high but he is going to charge you for 24 hours?!?! or does he just want it over night? a dealer should charge you something close to that to diagnose it. not sure if they do make a logger for 2g or not but if so i would get 1.

 

[McDeezy]

Well im positive its not a boost leak problem, my car hits boost fine. today I switched out my MAF and its still doing the same thing. My friend suggested my B.O.V was leaking or releasing boost too early, so I switched it out with another one I have and its still sputtering around 4.5k. So to recap, I have changed my spark plugs (gap to .28), spark plug wires, fuel filter, air filter, blow off valve, MAF, checked my firing order and still nothing has changed with my car. I would greatly appreciate any feedback or ideas. Thanks

 

[nytescion]

and you've done a boost leak test?

 

[McDeezy]

I'm about to get some soapy water and re-check everything. This car has been a complete nightmare from day one. My alternator keeps eating belts so i have to fix that before i can check for any boost leaks. When my friend was looking at my car yesterday, he said it sounded like it was leaking around the TB but he wasn't sure where. Well im gonna throw on a jacket and start working on it, hopefully soon i can get some answers.

 

[rEclipserGST]

Popabear- Did you ever replace your spark plugs with stock NGK's yet? I will PROMISE you that doing this will fix some of your issues. I had 2 ugly plugs in my car, swapped in a new set for like $12 and it runs go0o0o0o0o0d. So something to think about. Also, the plug wires. NGK wires as a little expensive, but worth it man. Other than that, I could bet that will fix your problem ESPECIALLY if you are not throwing a code.

Dayton isn't too far from the CO. Let me know how it goes buddy. I got some friends that party hard and live over there.

 

[doctor_shock10]

Platnum plugs are NOT the greatest plugs for our cars. I had a TERRIBLE experience with BOSCH platnum. They fouled out and misfired after 2 weeks of use. The Electrode is TOO small. They may last LONGER than a copper plug but the copper has a larger spark surface.

Do a boost leak test too. If you're leaking boost pressure the car will run really rich and BOG.

believe it or not but i had better hp #s on a dyno with the cheapest spark plugs advance auto sells then the bosch platnums both sets were brand new. so go buy the cheapy plugs and youll love em.

 

[McDeezy]

Ok so after spraying my pipes with soapy water, i found out i have two leaks. My j-pipe is leaking where it connects to my IC piping, and its also leaking where my upper IC piping connects with the lower Ic piping. Im not sure if the T-clamps are weak or if it because im connecting a 2.5" pipe to a 3" pipe?

Well i tightened down the clamps and re-sprayed them with soapy water luckily they're not leaking anymore but still didn't fix my problem. I'm getting pretty close to just lighting this car on fire. Any other suggestions?

 

[TomTom93536]

Mine does the same thing and i have no cat

 

[poppabear]

Was this problem ever resolved? my 2g is doing the same thing and im still trying to figure out what it is.

Sorry it took so long to update this thread, its been crazy at home and such.

It was the spark plug wires that was causing my issues. Replace the plug wires first before beating your brain apart.

 

[evancraig]

i believe my 2g is doing the exact same thing as well! any help would be an absolutely huge help! checked boost leaks as well, car is all completely stock minus cat-back exhaust and intake. cleaned maf sensor, checked over absolutely everything, still have no idea, no engine codes coming up either! i just put a new head on the car too, and it runs amazing except for this exact same problem. car pulls hard then seems like someone flicked a switch and it starts choking and sputtering and sounds exactly like a lawn mower until i let off the throttle and pin it again, seems to pull hard until i build full boost again and then it chokes off again. any help out there guys??? sorry i just saw there was a second page on here and i haven't replaced my plug wires yet, but will do that tomorrow and let you know. thanks.

 

[JMiller]

I'm having the same issue and will change plug wires soon, this thread was really helpful in giving me places to diagnose first.

 

[money42211]

My car dose same thing no boost leak.put new 255 walbro in it helped but still there when I hit 5k in the rpm.Any help would be great.

 

[98dsm31710]

Bumping a thread that's almost 4 years old, really. Do you have a wide band? Maybe you are running lean.

 

[miliman13]

Same boat, will try plugs and wires, air and fuel are solid.

 

[Kayo Stanciu]

Same boat, will try plugs and wires, air and fuel are solid.

Did the plugs and wires fix it for you

 

[miliman13]

Did the plugs and wires fix it for you

Quite the revival...
Yes i did.
The speed sensor on the transmission was slightly loose. It was missing the grenade pin.

It sends a signal to your ecu which essential activates a parameter that induces a bogging.

Think rev limiter*


Side note.. It took me gutting the bay, building a engine painting wire tuck.....
To figure it out in the end..