Topic: Car dropping boost? Read this thread.

[bun1t]

Ok so for the longest time I had a problem with my car dropping boost from 23psi to 18psi. It didn't throw a cel so I assumed it was a problem with my newly acquired Trifecta e47 tune.

My car was down for a little bit for a clutch install. I got the car back together, broke in the clutch and still had the same problem with boost dropping. I reset the ecu and the boost jumped back to 23psi so that ruled out a boost leak. When the boost dropped to 18 again I swung by Autozone to have my car scanned for codes. Even though I hadn't threw a cel, I had a soft code p2187. After looking around I saw that an exhaust leak could cause it and a result was reduced boost. I pulled the heat shield from the turbo and sure enough there was a leak coming from the side of the downpipe.

I saw there was a gap at the bottom bolt but when I tried to tighten it down it wouldn't budge. I ended up having to pull the downpipe off and bend the bracket that holds it at the bottom so the downpipe could seal against the turbo.

I drove the car today and no exhaust leak and boost stayed at 23psi. So two things,

1.  If your car is dropping boost without a cel and an ecu reset brings it back, check your exhaust for leaks, specifically before the 02 sensor.

2. If you're installing a Solo catless downpipe, double check to make sure it's sealing against the turbo as the bottom bracket can keep it from doing so.


On the bright side, my car ran a 12.6@110 with a leak in the downpipe.

[GASNGO]

My 08 RL with the DDM 2871 turbo and solo high flo cat is also throwing P2178 codes about every 10 or so restarts after I clear the code. P2187 is "to lean at idle". I have checked for leaking exhaust gaskets, checked all the t-bolt clamps that I replaced the OEM clamps with to no avail. I still get the code every so often. 

[tazz]

Yup something happened to mine just the other day. 
The bozo's at one of the dealerships just installed M10 bolts with 1.5 pitch instead of the stock studs and nuts.  Anyway the lower bolt on the cat to the turbo by the exhuast manifold was gone and slightly skweing the post cat o2 sensor as well as dropping about 2psi boost.

[miller11386]

My 08 RL with the DDM 2871 turbo and solo high flo cat is also throwing P2178 codes about every 10 or so restarts after I clear the code. P2187 is "to lean at idle". I have checked for leaking exhaust gaskets, checked all the t-bolt clamps that I replaced the OEM clamps with to no avail. I still get the code every so often. 

You may want to ask whoever tuned your car about this. I am going to guess you should log it with HPT to see if you have a leak somewhere. I am guessing that you have a leak somewhere. check O2 extenders as well. they have been a known problem spot if you use one.

[elff]

That's what I was going to suggest.


Remove the 02 extender, reinstall the 02 sensor, disable code P0420 and see if the code comes back.

[Brazen17]

Were you getting any kind of noise with that leak? The reason I ask is I recently had my turbo and exhaust manifold replaced and a few days later it has started making a noise, kind of like a rattle, under acceleration. I've put it up on jack stands and cannot find anything rubbing so I figure it must be some kind of leak.

[bun1t]

Were you getting any kind of noise with that leak? The reason I ask is I recently had my turbo and exhaust manifold replaced and a few days later it has started making a noise, kind of like a rattle, under acceleration. I've put it up on jack stands and cannot find anything rubbing so I figure it must be some kind of leak.

I didn't notice a noise but then again I have a catless downpipe with no muffler so it's really too loud to hear anything, lol

It could be the heatshield, check to make sure it's tight.

[elff]

bun1t
How do you NOT have a code reader?

[Brazen17]

Took mine back to dealership and yah, it was an exhaust leak. All good now!

[Critterman]

I find it totally amazing we take our cars in for service, they do their thing, we get the car and end up taking it back telling them what is wrong, in order to get the car fixed.

[miller11386]

where was the leak at?

[Brazen17]

where was the leak at?

One of the bolts on the intake manifold wasn't properly torqued. Started to rattle a few days after I picked it up. Also rattled at start up until engine temp hit ~120 and then it stopped until anything more than light throttle was applied.

[Brazen17]

I find it totally amazing we take our cars in for service, they do their thing, we get the car and end up taking it back telling them what is wrong, in order to get the car fixed.

Ain't that the truth! It was an honest mistake (if there is such a thing) and was a bit inconvenient to have to take it back but overall I am pretty happy with their service. So far the wife's redline has had a turbo replaced followed by the engine and now my turbo and exhaust manifold with not so much as a batted eye. Even thought they did question why the birdshit on the wife's waste gate threaded rod/nut was missing... In all honesty I never saw any birdshit on either the wife's or my GXP's threaded rod and neither was left "adjusted" for very long nor were they adjusted more than ~1.5 turns. Point being is I guess they could have denied warranty work if they had chose to but did not. So I guess life is good! Kind of funny because my first experience with them was less than stellar. Ever since it's been great. Sorry for the ramble but GJ has driven me to drinking. Again.   

[Gentleman Jack]

YEAH!!!! Company!

[Brazen17]

YEAH!!!! Company!

Sorry. I drink alone...   

















Besides, I'm more of a Jack Sparrow kind of drinker (hide the rum!) 

[Gentleman Jack]

That's just Rude!

I have enough for everyone. But you are close to a week long ban. Maybe even two weeks!

[Brazen17]

That's just Rude!

I have enough for everyone. But you are close to a week long ban. Maybe even two weeks!

Ban! Wait... from you or drinking? One is good and one is bad.     

[bun1t]

bun1t
How do you NOT have a code reader?

Because I haven't bought one? Most auto parts stores do it for free so there's really no reason for me to buy one.

[tazz]

That is true but it's alot less hassel if you own one.   What happens if your on the road with no parts stores in site or they are closed after hours then what. 
Not like there that expensive I think a low cost one from Harbor Freight runs $60 http://www.harborfreight.com/can-obdii-code-reader-with-multilingual-menu-98568.html .  I actually have 4 units that have code readers incorporated within the units DashHawk, Ultra Gauge, HPT and Diablo turner for my Ford truck since it's pre Can ODBII. They all are a bit different and I would say the HPT one gives a more readout and description and it's a tuner.

[tazz]

I only used my Ultra Gauge maybe 6 times at most since I prefer the DashHawk or HPT for the GXP but I have also used it on my Ford truck and it's OK.  I would sell it to you for $40 shipped and $10 of that is shipping.  I think I even have the box it came in as well as the window mount.

[bun1t]

That is true but it's alot less hassel if you own one.   What happens if your on the road with no parts stores in site or they are closed after hours then what. 

It's not like knowing the code will help me fix much when my tools are at my house. It would be nice but I don't mind going to the auto parts store.

[tazz]

No but it would be able to let you know if it's something to really be worried about.  You probably spend more than $60 every 3 weeks on coffee latte and soda just for your self unless you drink just tap water even bottle water is expensive.
Kind of like if your car throws a P0236 code then you might suspect that it's the connections to the T-map sensors and clear and be on your merry way.  If it's throwing a low fuel pressure code and your not smelling fuel then you know its probably the HPFP or the In Tank fuel pump and you will need to get that fixed ASAP since the car will not go into boost at that point.
Just don't see why everyone does not carry one with them just like a first aid kit and a canister fire extinguisher and a few tools all of which I carry in each of my 3 vehicles.  A small socket set as well as a small first aid kit barely takes up any room at all about the same as the air compressor in our small ass trunk.  The fire extinguisher fits on the side of the temple in the trunk and I even have my boys car seat on the other side of the temple.  Just trying to make a point that $$ should not be an issue here hell one dinner with drinks at a cheap restaurant like even Out Back will almost cost $60 with tip & tax and just 1 drink a piece.
But to each his own I guess.

[bun1t]

It's not about money, I just don't want one. Thanks anyways

[tazz]

That's cool.
If you ever need one just hit me up Hell I might even just Give the Ultra Gauge to you as long as you pay for shipping can't get any better than that just the kind of guy I am Trying to help those in Need.

[Kelu]

You can't delete codes with Trifecta cable?

On the bright side, my car ran a 12.6@110 with a leak in the downpipe.

Can you share more? Maybe on a different topic?

sixty?
tires?
fuel?

Awesome time