loss boost

i have a c-15 with a pdi stage 1 ecm and a stage 1 turbo and exhaust manifold . the engine wAS DOING 60 PSI BOOST NOW ONLY 40 CHECKED AIR 2 AIR AND BOOTS NO LEAKS ALSO NEW BOOST PRESSURE SENSOR NO HELP FROM PDI.

 

Have you talked to Jerry at the Pa. branch? You can get the number off PDI web site if you dont have it.

 

if the boost is controlled by ECM it may be something else that is wrong, like too much fuel causing high EGT so ECM will only boost to 40psi.

 

The etg never get above about700

 

The programming PDI did to your truck isn't causing the low boost condition. Why would you think that it was and that PDI should fix it? Why do you think they should spend a bunch of time trying to diagnose your mechanical problem over the phone for free?

You have to realize that the low boost condition is a symptom of a mechanical problem in the engine or truck. The ECM tuning didn't change from when you first had the tune flashed into the ECM to the time the low boost condition started........trust me, it is not a flash file problem in the ECM.

Have you inspected the turbos for damage or wear? Have you inspected the bellows between the turbos for leaks? Have you inspected the bellows between the pre-cooler and turbos? Have you inspected the band clamps on the bellows? Have you inspected the air intake supply hose to the air compressor? There are many things to look at on these engines compared to the earlier single turbo engines. Have you checked for any fault codes in the ECM? Since you're not complaining about a check engine light, I'll assume that you don't have any fault codes, so you have a mechanical problem, not an electronic one.

The people you'll talk with at PDI are sales people, not mechanics so their knowledge of mechanical problems is limited. They've also heard from customers blaming them for a problem with the truck after an ECM tune, to only have the customer find out later that it wasn't anything to do with the tune, but a problem with something else causing the low performance issues of the engine. If PDI sales people spend time trying to help you diagnose a problem over the phone they know isn't caused by the company's product they aren't making money for the company. Now they do have mechanics that work on trucks everyday in their service bays, you could stop by or make an appointment for them to diagnose and fix it just like you would at a CAT dealer. You can also take the truck to a CAT dealer to have them diagnose and fix the problem. PDI hides the tuning in the flash file, so you can take the truck anywhere in the country to have any problem that can occur with the engine fixed without the CAT dealer seeing the PDI tune in the ECM. Tell the dealer upon dropping the truck off that you don't authorise then to re-flash the ECM, that you are happy with the way the truck performs with the current ECM programming and that you do not want the latest and gr east file from CAT and you only are authorising them to fix the mechanical problem causing the low boost conditions. If they do want to update the flash file that you will not pay the bill. Make the service writer put this into the work order that the mechanic will be given.

 

I THANK YOU FOR YOUR INPUT . THE ENGINE IS A 6NZ SO IT ONLY HAS 1 TURBO I ALSO CHECKED AIR BOOTS ;CLAMPS,LINE GOING TO AIR COMPRESSOR, pressured up air to air to 60psi . took turbo apart to see if something may have hit ,both wheels apear to be fine .I WOULD LIKE TO THANK YOU AGAIN FOR YOUR HELP

 

Now we're talking about a horse of a different color.

What turbo do you have on this engine?

A 6NZ with a Stage 1 tune and turbo shouldn't build more than 45 psi of boost to start with. 60 psi of boost is telling me you have the wrong turbo for the horsepower application. Have you considered that the gauge may have been reading the pressure inaccurately? Has the engine's performance dropped since the boost pressure dropped?

 

I have a PDI stage 1 Turbo-big boss stage 1 cat #88606, PDI exhaust manifold #3359, its funny -this thing run like a scared deer first few times out, then for some reason I had three injectors stick, replaced them, has not ran good since, I sure thank you for all your help, kept giving me things to check, because so far everything you have mentioned I have already checked, if any way possible can we talk on the phone, one more thing I rebuilt this engine while I was rebuilding truck

 

The injectors sticking isn't the programming this is an internal mechanical failure of the injector. Most of the time it's a sign of low lubricity of the fuel being used. The Ultra Low Sulfur Diesel Fuel doesn't lubricate the older injectors designed to run on High Sulfur Diesel Fuel, especially in the summer months with high fuel temperatures in the fuel tanks. The fact you lost three of them would also make me wonder about internal wear issues in the other three.

The earlier 6NZ uses an injector that is part number 191-3003 or a reman 0R-9257, neither of these injectors were built for ULSD. Throw high fuel temperatures into the picture and you have sticking injectors. Has this problem gotten worse as it got hotter outside this summer?

 

My injector are 10R- 8501, I only haul my own equipment, truck has 6500 miles on it since this problem started, and about 7500 since complete overhaul, it has not gotten worse being hotter outside, still at a loss, rerunning overhead again just to make sure, but i have been doing engines for along time, know its ok, but just double checkin myself, any other things to check, and on the ecm, can u give me break down on what its main purpose is, just so i know what i'm thinking is true
thanks for help