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High boost - Yauchout - 01-12-2021

I have a CM2350 factory 550/1850 demandated by a respected member of this form. My boost levels are higher than usual showing 40 PSI on the factory boost gauge on a hard climb 1600 RPM full throttle. I've done an injector leaked down test injector performance test installed a new IMAP sensor no engine codes truck passes both the leak down and performance test. Is there a test I can or should perform on the VGT to eliminate it as a problem should I hook up an aftermarket boost gauge to make sure it's just not a bad factory gauge. I'm not sure where to go from here


RE: High boost - Rawze - 01-13-2021

anything much more than 33,34~ish psi max or so will cause harm to a 2350. That needs to be fixed right away.

Has it been like this since the programming was done? -- or did it change suddenly?

If it suddenly changed...
Maybe do a turbo inspection to see if it has full range of operation ... and make sure the turbo passes a calibration test.

If it has been like this since the programming...
If all is well with the system then have whoever made the program lower the boost tables to bring it back in spec, simple as that.


RE: High boost - Yauchout - 01-13-2021

(01-13-2021 )Rawze Wrote:  anything much more than 33 psi or so will kill a 2350. That needs to be fixed right away.

Has it been like this since the programming was done? -- or did it change suddenly?

If it suddenly changed...
Maybe do a turbo inspection to see if it has full range of operation ... and make sure the turbo passes a calibration test.

If it has been like this since the programming...
If all is well with the system then have whoever made the program lower the boost tables to bring it back in spec, simple as that.

it had been around 35-36 ish factory gauge is a little hard to tell since the programing. it was higher close to 38 with the mandate intact. it seems to be higher here lately that's why I changed the map sensor thinking it was just reading incorrectly it had been in about 100K. ran a leak down had a injector leaking that I replaced still the same results. I am parked so I went ahead and ran a calibration test it passed. I will inspect the turbo its self when the sun comes up and I can see better and let you know the results


RE: High boost - Rawze - 01-13-2021

(01-13-2021 )Yauchout Wrote:  it had been around 35-36 ish factory gauge is a little hard to tell since the programing. it was higher close to 38 with the mandate intact. it seems to be higher here lately that's why I changed the map sensor thinking it was just reading incorrectly it had been in about 100K. ran a leak down had a injector leaking that I replaced still the same results. I am parked so I went ahead and ran a calibration test it passed. I will inspect the turbo its self when the sun comes up and I can see better and let you know the results

yeah, 35,36 is on the high side of things... it should have been lowered a touch back when it was done initially if that was the case.

(putting this here for reference)...
As far as it being 38~ish before the demandate, that is quite normal. It is this much higher because the EGR gas is bypassing the turbo and making it a few higher + artificially lowering the A/R ratio of the trubo. With no more EGR gas, this 38 is too much for the engine to handle and the A/R ratio is upwards of 2.4 or more and causes the engine to labor against its own exhaust gasses.

your always welcome to pull a copy of the program out and e-mail it to me for a review, an update (if the program is actually good), etc. - I can lower the boost tables in the program that was sent while I am at it of ya like... it is easy to do.


RE: High boost - Yauchout - 01-13-2021

(01-13-2021 )Rawze Wrote:  
(01-13-2021 )Yauchout Wrote:  it had been around 35-36 ish factory gauge is a little hard to tell since the programing. it was higher close to 38 with the mandate intact. it seems to be higher here lately that's why I changed the map sensor thinking it was just reading incorrectly it had been in about 100K. ran a leak down had a injector leaking that I replaced still the same results. I am parked so I went ahead and ran a calibration test it passed. I will inspect the turbo its self when the sun comes up and I can see better and let you know the results

yeah, 35,36 is on the high side of things... it should have been lowered a touch back when it was done initially if that was the case.

(putting this here for reference)...
As far as it being 38~ish before the demandate, that is quite normal. It is this much higher because the EGR gas is bypassing the turbo and making it a few higher + artificially lowering the A/R ratio of the trubo. With no more EGR gas, this 38 is too much for the engine to handle and the A/R ratio is upwards of 2.4 or more and causes the engine to labor against its own exhaust gasses.

your always welcome to pull a copy of the program out and e-mail it to me for a review, an update (if the program is actually good), etc. - I can lower the boost tables in the program that was sent while I am at it of ya like... it is easy to do.

that may be what i need to do i currently have insite but not the software to pull a copy of my file but I will try and work on getting that


RE: High boost - Slowmotion - 03-15-2021

Hello all, I have what I believe to be a similar issue. The engine is an cm2250, 2012 in a T660. Had it Demandated about 3 years ago and do not believe the tune is as it should be. 675,000 miles and head has 4 cracks. Planning on unframe while I'm in this deep. Where do I begin with checking the ecm. I am able to remove it and get it to a work bench. Thanks for any insight into this matter. BTW, love this web / forum.


RE: High boost - tree98 - 03-15-2021

You need the c a l t e r m program to pull a copy of the file. Then you email it to Rawze and he will tell you how completely butchered it is.


RE: High boost - smorgan87 - 03-15-2021

Be a good idea to swap those factory gauges out for an capillary tube type. Rawze likes the glow shift brand, im an autometer fan. Both can be got from amazon


RE: High boost - amermextrucker - 03-15-2021

Where can one obtain CT ?