My Coronado, 14L Detroit nagging issues

I think you said that you run to Lexington ky sometime. If you want to pm me I can give you full details on everything but let's just say a shop here in cincy, which would be out of your way some but would be worth it, worked magic on mine. My truck put 319hp to the tires on the dyno. By the time they got done with it they got 414hp an 1609lbs to the tires out of a 455 series 14.0l. It's maxed out there is nothing more that can be done due to injectors an turbo. But on the injector subject I wouldn't let the replace them off a 80% sure guess. It's a 3000 plus dollar job an the only way they can test the ddec5 injectors is to actually pull them out. To me sounds like the injectors are out of calibration which can be adjusted threw a tune not by replacing. Mine where all over the place from a .45-.62 between the 6 of them an one wasn't even working due to a bad rocker arm.

 

Does the fuel look dark in the tank? Pop open your fuel cap and ramp on the engine, check for air bubbles in the tank. Possiible you are getting either air in the suction side, and or your injectors are causing your fuel to aerate. Another thing I didnt see done was blowing your delta p S tubes with shop air. Make sure they are free of carbon. With your turbo boost dropping out, looks like that new vpod could be getting hot and becoming inop. It wouldnt be my first new vpod I have seen going bad. Go under the engine where the vpod is, and check the harness to see if it is brittle from high exhaust temp. Whats your fuel pressure? If you have access to a laptop, monitor the egr temp with the valve shut and make sure the temp isnt climbing.. Do you have any codes?

 

barometric pressure wrong says it all -it,s not injectors , pull all your plug ins out and check it standard , baro pressure, intake and boost pressure should corrispond

 

Any updates on this, I just bought a 14L Detroit, 10spd, 3.55 rears....

 

I had a turbo actuator blow the diaphragm on me. Got the part $450 and installed it on the side of interstate. Used me log book ruler to measure the arm so when I installed it would be back in same position. After install finished my run and the truck ran like crap. Took it the shop and the only way to get acuator calibrated properly is for a shop to do it. They have to be put on a dyno, and a tune has to be put into the ecm for them to adjust it for the open and close positions. Sound crazy but after another $327 dyno/calibration truck runs great. So if you replaced your acuator and never had it calibrated then I would put money on that being your problem.

 

Best advise I have is to save 6 grand put it in a safe place. When your turbo and other egr bs start acting up, spend the extra 2 grand an do away with the vgt turbo and other parts. Increase your fuel economy, reliability, power, and put your mind at ease. It will cost you 4 grand to replace the stock garret so the extra 2 grand will pay for it self within a year. Can't go into full details due to forum rules but you won't want to have a emission check done after words.

 

my friend's 06 coronado has terrible mpg. he bought w/o rear axles, tranny, and bad rebuilt. He placed 13 sp and 3.42 rear and got 3 mpg. He tried to take off egr and got 5 mpg. anything else to increase mpg other than egr and speed?
then my uncles 06 century. He replaces the turbo and egr nearly every 6 months. Gets 6.5 mpg. any advice to reduce that much replacement?

 

am a co. driver here; 06 14L Columbia. Had a whistle develop under hood; they changed turbo, egr valve, still whistled. Finally traced it down to a bad deteriorating exhaust manifold gasket.

Runs likes a 'b****' now.