Question for Turbo-Master owners

[markrinker]

I recently installed Turbo-Master wastegate controllers on both of my 6.5TD trucks. At stock settings, they function fine. If I attempt to turn up boost slightly, I get code 78 (Turbo Wastegate Solenoid Fault).

Shouldn't the code be 61 or 62 (Turbo Boost sensor curcuit high/low) when adjusting this?

What have other users found? Any suggestions on how to fool the computer into NOT setting the 78 code?

[whatnot]

You need an electronic boost controller to fix it. Or just pur some resistors in the boost sensor circuit.

[markelectric]

I have three of them in 6.5's and one in a dodge. If I were you, I would get in touch with Bill Heath. You are probably not the first one with this problem. Bill is a wealth of knowledge on these diesels.

[gmctd]

Boost sensor reads baro at idle and lo rpm, around 14-15psi and 2.5v for baseline reference. Boost Sensor failure DTC's are if the sensor does not fall within that range at that time - sensor is failing\failed.

DTC-78 is if boost does not drop when the PCM calls for reduced boost. DTC-78 seems not to recognize low boost, as with wastegate system failure.

Only way to fool PCM is with electronic Boost Control (easiest) or alter the map in Eprom or Flash (not so easiest).

[GARY PAGE]

Call Bill and get the chip for your computer. The install directions reminded youif you set above 7PSI the stock computer program won't like it. I have both parts and it works great. I sit mine at 12 PSI and it will surge to 15. It makes quite a difference and the whistle shound is neat too...

[Journeydog]

"gmctd" said it pretty well. Let me offer my two cents as well FWIW. I battled this '78' effect for a short while 'til I finally realized that the boost sensor wasn't at fault. The '78' is set because the wastegate solenoid isn't reacting to orders by the PCM to reduce boost. Heck, it can't because it's function is now nada because you took it away when you installed the TM controller. The PCM says to the wastegate solenoid "cut the boost" and the solenoid sucks and does it's thing, but nobody's home. PCM tells the world that the solenoid is a bad boy and sets a '78' so you'll know about it too. And, the PCM will reduce fuel, so your performance ain't great. I didn't find the sweet spot with a boost controller, so I was going to buy Bill Heath's chip anyway. It did the trick.

[markrinker]

Thanks - maybe I can get a deal on buying two at once!

Mark Rinker

[markrinker]

Bill Heath's response:
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Hello Mark,
The code is as a result of running a too high boost pressure or possibly as a result of the input from a map sensor which is out of calibration. If the T-M is set so that it delivers more than about 8 psi, there is a strong likelihood of setting the code. If the map sensor is out of spec, it could be telling the computer of a too high pressure even though one does not exist. Another posibility is that the intake temp sensor is out of range. It would tell the computer that the intake air temp is higher than it really is which would indicate boost pressure over the parameter built into the computer. A scan tool will show outputs from both these sensors.
You might try simply backing the T-M setting down by adjusting the spring to a dimension that is 1/4" longer. The engine will still run much better than stock by virtue of the TM influenced, steady boost pressure level. A max pressure of 6 vs say, 8psi will have little affect on output when factory fuel delivery is being used, so reducing the pressure setting enought to stop the problem is not a bad thing.
I hope this helps, Mark.

Best regards
Bill
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[markelectric]

I told you he would have an answer that would make sense.