High EGT's, questionable ICP, turbo boost,
Hello! I prolly need to develop a couple of different specific discussions, but thought I would start with an overview:
A year ago, I had a repeated random no start issue. Probably was the IPR in hindsight, I replaced the valve cover gaskets and ICP sensor, the dealership told me I was only holding 1400-1600 psi, so they said I needed a new HPOP. No start problem fixed, fast forward one year and I discovered that my ICP was still 1400 to 1600! Not sure if the dealership even tested it when it was done, but I was glad the damn thing started reliably. We decided the injectors must be bleeding oil pressure, so we replaced/upgraded them and got a huge improvement in ICP.
I have installed/replaced the following recently: Full Force stage 1’s, standard IH up pipes (were leaking profusely for a long long time), trashed the superchips for a dp tuner, ICP system including sensor, stock pump, and regulator, valve cover gaskets and harnesses, installed napa diy 6637 kit and 4” turbo-back with aero-turbine muffler, Wicked Wheel on the stock turbo setup, ebp sensor, Cps sensor (both were giving me trouble). I asked Mech. to do a compression check while replacing inj, but apparently his equipment wasn’t all up to par, so he only got a brief glimpse of a couple of cylinders and he said, it was tired, not dead. I really wanted numbers, but unfortunately didn’t get them. Apparently his tester pulses wildly or something.
Oh yeah, now I am monitoring vitals via Edge Insight CTS with egt probe.
From 0-80 @ WOT, by ICP will maintain about 2650-2750 psi. After the pressure levels off, I see about 40% IPR duty cycle, but it slowly climbs to approximatley 60-65% by the time I have to let off the throttle or get busted by the cops. That is in 120 Race tune. Injector pulse width runs about 3.66. EGT’S WILL easily climb to 1450 with the truck empty. Turbo boost struggles to get over 22 psi.
80 Econ tune seems to maintain slightly higher psi and will actually spike to 3600 or so and stay there for a few seconds after going from 100% throttle to 40-50% throttle. Similar boost numbers, lower injector pulse width, and slightly lower egt’s.
Stock is a complete dog since installing the ss injectors and custom tune. It is way less responsive than ever before, even with stock injectors and stock ecm. It’s very slow IMO, but my opinion could be slightly skewed by that rippin 120 tune!. Boost pressure never ever gets above 14 or 15 psi in stock, no matter how bad I abuse it. Fuel atomization seems to be very slow IMO.
Also getting compressor surge when pulling a grade empty. (note have installed wicked wheel)
Also have idle that sort of pulses and sometimes sounds like it is missing. In addition, for some reason, I am not sure if it is the tuning or what, but it likes to reach down and shift into a lower gear at strange times like when I am doing 50 or 60 and let off the throttle. It never used to do that, it is not a big problem or anything, just thought I would bring it up in case it raised any flags to you.
I am not sure if my turbo is healthy, but I think with those EGT numbers, something must be going on there. Plus, 14 psi in stock tune sounds really low.
I have always wondered if my ECM is nutty. The monitor tells me I am getting 24-26 mpg’s average when in reality I am lucky to get 12 mixed driving. (The head’s up display never worked, so this is the first time I have seen those false mpg numbers).
Finally, I worry about the pistons at this point because if the EGT’s got that high empty, I can only imagine how high and how many times they were high in the past. Especially before I replaced the up pipes and injectors....
Question, should I throw this truck away, or where to go from here. I want mid to high teens on mpg's and I want to be able to pull a trailer like all the other diesels I see (and maintain <1200 egt!)
Last edited by dpandj1977; 05-03-2012 at 09:41 AM.