03 H.O. 6 Speed ,Barking in 6th gear, No Load, Stock HE341,BBI S .1s, No tuning

[Darkbloodmon]

Another new symptom when I'm trying to get other things done on this truck.

This is a stock truck with new injectors (BBI Stage .1s), a freshly reman/blueprinted HE341 from Turbo Resource. Exhaust manifold and hot side of the turbo are ceramic coated. Turbo has been on for less than an oil change interval.

I just noticed these symptoms within last two days, a turbo bark coming off the throttle in 6th gear un loaded at an elevation of 704' above sea level. I can only replicate this in 6th gear after hard acceleration. This has never been an issue before on this turbo coming off the throttle in 6th from a slight pull. Even on highway on ramps.

My previous turbo that came on the truck was factory and had been wasted at 227K miles; the wheel came in contact with the housing at 1800rpm+. I have no real base line to compare too though I don't remember having turbo bark on the previous unit. I keep a log of any sound, symptom, observation, etc. with my truck religiously for every key on key off, repair or maintenance item.

Unfortunately I do not have gauges as I've just been blindly sweeping off big failure items (injectors, fueling, turbo) from the list before they happen and require diagnostics and down time to pinpoint.

Is this a normal occurrence on a stock application?

 

[petersonj]

Is this a normal occurrence on a stock application?

This is a stock truck with new injectors (BBI Stage .1s), a freshly reman/blueprinted HE341 from Turbo Resource. Exhaust manifold and hot side of the turbo are ceramic coated. Turbo has been on for less than an oil change interval.

I don't have the answer to your question, but in the meantime if you come off the throttle at a slightly slower and smoother rate after hard fueling, the turbo bark should not be present. As you probably know, the bark is caused by sudden defueling right after maximum fueling. The high boost pressure begins to flow backwards and tries to stall the compressor because of the sudden loss of drive pressure.

The engine is not quite stock anymore with the different injectors and coated exhaust. Has the wastegate setting been increased? Is the wastegate blocked? What is your boost pressure at a given rpm? Just some thoughts that might help.

- John

 

[Tuesdak]

Call Turbo Resource... Meanwhile do your best to keep it from barking.

Now I ran a Ball Bearing stage 3 turbo known for barking and never had it happen IMO due to a better aftermarket camshaft.

 

[Darkbloodmon]

I don't have the answer to your question, but in the meantime if you come off the throttle at a slightly slower and smoother rate after hard fueling, the turbo bark should not be present. As you probably know, the bark is caused by sudden defueling right after maximum fueling. The high boost pressure begins to flow backwards and tries to stall the compressor because of the sudden loss of drive pressure.

The engine is not quite stock anymore with the different injectors and coated exhaust. Has the wastegate setting been increased? Is the wastegate blocked? What is your boost pressure at a given rpm? Just some thoughts that might help.

- John

Wastegate has been left at the final assembly marks from Turbo Resource, I've not touched other than disassembly for coating and painting. What could cause the wastegate to become blocked? Also how much of an increase would stage .1s and a coated hot side result in? I didn't have a good baseline to compare on either injectors or the turbo when I first got the truck but I don't imagine the slight changes are as marginal in drivability as 50 overs and a S467.7, I chose the stockest improved designs as possible for replacements, just to keep things near normal performance spec before looking to tune later (much later....) down the road.

The part that's not lining up is that immediately after dropping it in and the following months after I've had no issue with bark even with 6th gear pulls coming off the throttle hard, furthermore I've not noted anything to elude to this problem previously in my log, I'm meticulous about anything note worthy out of normal operating condition. I don't romp on her, she's my daily and I know she's not 100% with all the catchup work I've been doing from the previous owners making me that much more mindful of anything abnormal.

I don't have gauges (Yet!) so I wouldn't be able to know the boost: rpm, I've been really meaning to get a set before something like this happens when I'm trying to pin down some fault or hiccup on a system.

 

[Darkbloodmon]

Call Turbo Resource... Meanwhile do your best to keep it from barking.

Now I ran a Ball Bearing stage 3 turbo known for barking and never had it happen IMO due to a better aftermarket camshaft.

Sent them an email, forgot Monday is a holiday so I figure I won't get ahold of them till midweek or so. It's still drivable, and not hard to be mindful of throttle in 6th but It's really strange that now there's an issue were there wasn't before in 6th gear pulls. I can't recall any warning signs, or odd noises leading up to this either.

 

[NIsaacs]

Have you checked your air filter and box? Maybe a rats nest in it or otherwise restricted.

 

[Darkbloodmon]

Have you checked your air filter and box? Maybe a rats nest in it or otherwise restricted.

Clean, filter minder is green as well, I checked the jam nut on the wastegate actuator and it hasn't moved or backed off from its set point. All my clamps on the turbo are tight, no soot around gaskets of the manifold.

 

[Darkbloodmon]

Update for the curious eyes following, After a few emails back and forth about my observations and symptoms with Tom S. From Turbo Resource, He's at a dead end on being able to diag. without any numbers. I've got to get gauges to do that.

Does anyone have any experience with an the Edge CTS3 on the older Pre-canbus trucks? I like the simplicity of the add on sensors and the modern data logging features. Also the idea of running lines over the engine bay and piggy backing isn't something I'm keen on as I clean up previous wiring. It'll get majority of the numbers I need from the OBDII port, Though I'll need to run an EAS for the EGT, Trans Temp, and potentially fuel pressure. I know it'll get rail pressure.

Figured I'd be at or near the same price point with the amount of gauges I'd be running; minus all the wiring and routing is a plus, and data collection would be a lot easier to organize as well. Thoughts?

 

[Darkbloodmon]

Another tid bit for diagnosis.

My setup is near stock, and I'm not tuned. Something has changed. Let's assume there isn't anything wrong on the turbo or exhaust side mechanically. It is ceramic coated but I don't think it would be spooling faster now than right after install from the coating alone. It's unlikely for that to have changed.

On the fuel system, Injectors are new, ECM is updated, FCA is new, fuel delivery is replumbed with a Fass and fuel bowl delete. The CP3 is factory with 229K mi and leaking what I thought to be oil, but after digging in the archives learned that it's not leaking oil from behind the crank case cover but diesel from the weep hole, indicating seal failure.

So here is the question, Could a worn CP3 pump over fuel the rail of what is commanded therefore increasing the amount of fuel injected leading to an increase in EGTS which spools the exhaust side of the turbo faster and hotter leading to an over boost condition that the waste gate was not set for?

 

[DonFitzwater]

So here is the question, Could a worn CP3 pump over fuel the rail of what is commanded therefore increasing the amount of fuel injected leading to an increase in EGTS which spools the exhaust side of the turbo faster and hotter leading to an over boost condition that the waste gate was not set for?

Nope. After a hard acceleration does the engine hang at a particular rpm after releasing the throttle?

 

[Darkbloodmon]

Nope. After a hard acceleration does the engine hang at a particular rpm after releasing the throttle?

I don't get any hang, But I can pull hard and get of the pedal sharply in any gear without bark but 6th. I posed the same question to Tom S. at Turbo Resource, he says it's possible. What's your reasoning behind it not being possible?

Any feed back on a CTS3? I'll give them a call tomorrow and see what the damage would be to get all the sensors I need.

 

[DonFitzwater]

I don't get any hang, But I can pull hard and get of the pedal sharply in any gear without bark but 6th. I posed the same question to Tom S. at Turbo Resource, he says it's possible. What's your reasoning behind it not being possible?

Any feed back on a CTS3? I'll give them a call tomorrow and see what the damage would be to get all the sensors I need.

A worn CP3 won't cause the symptoms you are having in my experience. Low fuel pressure would typically be the result.

 

[Darkbloodmon]

A worn CP3 won't cause the symptoms you are having in my experience. Low fuel pressure would typically be the result.

Where would you speculate the extra boost is coming from? Assuming the turbo and exhaust side is without fault.

My logic behind a worn cp3 over fueling is that the FCA is metering fuel for specified dimensions of the cp3, If the hard fitting parts are worn or out of spec allowing for a leak then the FCA will add more fuel to replace the lost volume and maintain pump pressure continuously.

 

[AH64ID]

A worn CP3 will cause low rail pressure which could lead to less fuel, not more.The CP3 just supplies the pressure, the ECM then opens the injectors based on desired fuel and actual pressure.

Without gauges how do you know it’s excess boost?

Are you planning on a tuner?

 

[Darkbloodmon]

A worn CP3 will cause low rail pressure which could lead to less fuel, not more.The CP3 just supplies the pressure, the ECM then opens the injectors based on desired fuel and actual pressure.

Without gauges how do you know it’s excess boost?

Are you planning on a tuner?

I'll have to read up on the the cp3 functionality in my FSM.

My speculation to why I think i'm getting more boost is because of the compressor surge "bark". Nothing on the exhaust side has changed since turbo install, It should not be making any more boost than when first installed. Something has changed elsewhere to cause it to increase the amount of heat on the exhaust side causing more spool up. More fuel is one of the things that can do this. More fuel injected, bigger combustion, more heat, turbo spool, more boost, and now boost that the wastegate wasn't set to handle. The truck is on factory mapping without tuning, additionally the only weak point in my fuel delivery or injection system is the CP3 everything else has been replaced with new components.

Tom S. from Turbo resource agrees from this perspective of assuming all is well on the Turbo/Exhaust side, Something has changed elsewhere to cause the turbo to boost more than previously observed as I had no issue coming off the throttle sharply in 6th before. The "Bark" is the indication that I am over boosting as the air is stalling due to an excess supply.

I am looking to use a tuner (HPTuners) once I get all my issues with the truck straightened out which is no time soon at this rate.

I am looking to get gauges on my truck to help with this diagnosis, Since I have no previous base line, I'll be looking for numbers that are outliers to factory specs since majority of my replacements have been near factory performance. For example I should not be seeing 40psi + of boost on a monitor for a Ceramic coated HE341 and stage .1 BBI injectors on a stock fuel map.

What do you think is the source of my compressor surge?

 

[AH64ID]

If you’re not getting an overboost CEL then I doubt it’s making that much extra boost, and people push HE341’s well above stock psi all the time without barking.

If you’re going to get custom tuning I’d go MM3 and UDC Pro over HP and a CTS3.

 

[Darkbloodmon]

If you don't think its getting more boost then where do you think the bark is coming from? I know it's compressor surge without a doubt, but how is it being caused on a near stock application where previously it wasn't a symptom.

I'm going to clean out my manifold related sensors incase they're getting a false reading.

 

[AH64ID]

Bark occurs when the exhaust flow is insufficient to keep the pressurized air flowing into the motor vs back out the compressor.

It doesn’t have to be boost caused, it can have something to do with exhaust flow too.. which you have modified with the turbo/coating.

 

[Tuesdak]

What do you think is the source of my compressor surge?

Keep in mind we aren't in the truck with you, but, I am not convinced you are experiencing a turbo bark. It would make more sense if it did it in other gears at the same engine RPM. Possible the load on the engine is higher in 6th and you have boost creep from higher altitude. Did they suggest backing off the WG any? Lack of gauges would hold that suggestion back I expect. Again just a double check that you are going after the proper thing.

I used a Smarty Touch on my 2003 with the EGT probe for gauges.

The engine moves a lot in the mounts from full power to no power. For example another ride would make interesting noises as the cooling fan hit the trans cooler lines and shroud. It had a sagging engine mount.

I would go over the clamps and boots on the intake and intercooler. Just in case one blew out.

 

[Darkbloodmon]

Bark occurs when the exhaust flow is insufficient to keep the pressurized air flowing into the motor vs back out the compressor.

It doesn’t have to be boost caused, it can have something to do with exhaust flow too.. which you have modified with the turbo/coating.

Day one after turbo install I had no issues and it stayed that way till the 16th of Jan, nothing has been changed since then.