Hi all....

I have a 2003 that has been a PITA. It has 92,000 miles on it.

It had that EGR issue a few times, where it surges and sputters and runs really poor.

The last time they replaced the EGR valve, they found oil in the intercooler and intake system. The turbo bearings were bad, so they changed the turbo, intercooler, and EGR. Prior to the EGR issue it ran really strong. It would spin the tires all through 1 and 2 (automatic) by punching it from a dead stop.

After I got the truck back and spending $3000, it was dog. I would wait forever for it to pull, and it would finally start pulling at 2500-3000 RPM. Just as soon as it pulled, it would shift and drop out of boost. They agreed, and wanted to install a new $500 computer as a guess. I said no.

Another dealer said it was the fuel filters, but that didn't do a thing. They wanted to change the MAF sensor and an exhaust pressure sensor, but the firmware in the truck doesn't even watch the exhaust and it did not have MAF codes. Since they wanted to change a part that was not even used any longer, I picked my truck up with a $220 bill for no improvement at all.

I took it back to the first dealer, and they agreed. After having the truck a few weeks they said it was dropping in and out of boost. They did something, including new firmware upload, and now it has a wider power band but is very slack spooling up.

I pulled the boost gauge from my Mustang, and connected it to the 6.0. Stuffing the accelerator from a stop, the boost is 5 pounds at 2000 RPM. It goes to 17 pounds by the time it is in second or third gear and stays up around 15-20 pounds.

If I power-brake the truck to spool up the turbo, it makes 15-17 pounds at 2000 RPM, but it takes about 4 seconds or more to spool up. If I spool up and release the brake, it burns the tires off all through 1st and 2nd gear, just like it did before they changed the turbo and intercooler.

The problem is this. Pulling out in traffic, especially with a trailer or load, or when calling for boost to pass someone, always takes a long time to get any power. If I watch the boost gauge, it's a good 3-4 seconds before it makes any significant boost.

It's like it has a really slow spool-up time.

Is this normal for other trucks? Mine used to spin the tires if I punched it. It pulled really strong off idle, without any really noticeable lag. Now it is a slug for maybe 4 seconds, and barely has boost initially, but pulls strong if I wait that time out. I didn't pay $4000 total (now) to have the truck slow down, but if the new normal is slug-like, I guess I'll have to live with it.

Thanks,

Tom

 

Well oldman first thing , oil in intercooler is normal , oil in the turbo plumbing normal . It comes from the crankcase vent oily gases get sucked though the turbo and intercooler and plumbing . With the work they did it should run great . Do you know if it has any exhaust leaks like around turbo or the up pipes ? that could cause your lag problem . Can you smell diesel fumes in the cab ?

 

Oh one more thing turbo bearing being bad would put oil in the exhaust . That is the side blows oil when they go bad . Not intake side .

 

Thank's for the replies.

There aren't any leaks, all the exhaust and inlet lines are secure and show no evidence of leaking.

The turbo was bad, I looked at the old turbo and I could push and pull the shaft in and out a noticeable amount. I'd say it had .050 end play or more.

This truck only has 92K miles, most of which are Interstate steady speed 70 MPH without a trailer. The rest is rural country driving.

Does that lag sound abnormally severe? Could they have put a bad turbo on it, or missed something?


Tom

 

I have some turbo lag from a standing start, especially if I nail the go pedal too quick, but nothing like 4 seconds worth. When I first got the truck I tried to drive it like a gasser and had a couple of scares in traffic. Sound to me like there's a problem. It could be binding at the unison ring or VGT actuator, or a CAC or exhaust leak, or obstruction in the intake or exhaust, or a fuel delivery problem.

 

Since it never had this issue before they changed the turbo, what are the chances the turbo is bad, or they messed something up changing it?

Not that I claim to understand the system, but it just seems to me if it was fuel delivery, or obstructions, it would never make power properly. It makes ton's of power if I power up against the brake and spool it up. It will actually smoke both rear tires for hundreds of feet. It just takes at least 4 seconds or more to spool up.

As a matter of fact from an idle start, if I watch boost, it only makes around 5 pounds as it slowly crosses 2000 RPM. If I stuff and count 1001, 1002, 1003, 1004...I get to 1004 before it goes much over 5 lbs boost. It doesn't make 15-17 pounds, from an idle start, until it is well into 2nd gear.

Is there something I can measure? Is there an electronics control line or pressure line that tells the turbo to spool up that I can watch?? I am measuring boost in the intake, near the rear, away from the inlet port.

I just hate to throw money at this thing guessing.

Tom

 

There is an X-gauge for VGT duty cycle if you have a ScanGauge. It reads 0-100%. I'm sure the dealerships IDS could read it and possibly a scanner with "live data" capability. You would know if the signal to the actuator is low or late. As far as a mechanical issue like binding or somthing, I think you would have to pull it and inspect.

 

Sounds like they did not do a VGT relearn. Do that and see if it is better.

 

Try the relearn mention above^^^^^



But your Boost numbers are Low if all your seeing is 20 PSI BOOST

24-28psi BOOST is optimal range

And honestly alot of diffrent sensors and other things come into PLAY to make Boost

Since the Turbine wheel is Spun with Exhaust Gas that means EVERYTHING Before it Must work Properly

Your best bet is to get a ScanGaugeII or something to check it out the sensor part anyway

Theres a couple other check you will have to do like the uppipes they can Crack right at the flex joint B4 the turbo and you can Loose some there


If you dont want to mess with it then you can find a GOOD 6.0L mechanic from folks here Not all Mechanics are created equall

But with a SGII you can see alot of the numbers

a step better would be AE ford bundle this will allow testing of the VGT valve

 

Benny,
I'm thinking his numbers may be different than what we usuially see.

 

OH BOY


Your Right Rusty I didnt see that


But I dont think it makes a diffrence as we get ours from Middle of the intake Passenger side at the MAP sensor

Im thinking the Boost reading will be the same anywhere the PSI is measured Just as Long as its Measured AFTER the TURBO

And after the Intercooler would be the best its cooled and IDK how much Heat/cooled has an affect probably minimal but IDK


What did he do Drill a Hole in the intake manafold

 

His gauge should figure ambeint Pressure to


But the Bottom Line here is You need a Gauge to see what the PCM is seeing

Nothing matters but what the PCM sees its controling the Truck

so the AM gauge is OK to a Point but when a problem does exist the aftermarket gauge dont mean nothing

 

I thought everyone that puts an Aftermarket Boost Gauge on just TEE off the MAP Hose

IDK how the AM Boost gauge works exactly it needs to figure Baro or ambeint pressure in

I dont get into some of these AM Gauges Fuel Pressure OK EGT OK But the rest may as well come from OEM senders cuz when there is a problem they dont matter as much

And again it still comes down to what the PCM is seeing Bottom Line

 

I can buy what it takes to check things. Where do I get a SGII, or AE Ford bundle?

I am used to working with the EEC in my old 89 Mustang, which is supercharged. I use a Tweecer and other things to watch that computer, and can record sensors for playback. I'd like to do my truck that way, too.

Tom

 

SGII is a Great unit Lots use it here. will see all sensor on engine and some trans
Best deal going for gauges

My SGII has helped me a ton its paid for itself many many times over
Its 160.00 from auto Zone or
ScanGauge - Trip Computer + Digitial Gauges + ScanTools

AE with ford bundle does it all see sensors does Ford specific testing ABS Tranny all of it
Cylinder Balance test for injectors
IIRC its 360.00 Get with Clay at Riff Raff diesel he can tell you about it just 1 thing is I heard vs 10 AE with ford enhanced didnt do cylinder balance for 6.0L IDK if it was BS or what but CLAY will Know

Riffraff Diesel Performance Parts | Ford 7.3 diesel | 7.3 powerstroke | Ford Powerstroke | 7.3L Powerstroke Parts


You have maybe a 85% chance ScanGaugeII will show you whats wrong you will get the values with SGII and post them and a few of us can say good or Bad values

Pick your poision

SGII great to keep in truck

AE is computer program for your Laptop

I chased a no start in my own truck with the SGII a week ago and fixed it by not paying a tow bill and diagnostic fee SGII paid for itself its really saved me Hundereds$$$