Where's the turbo boost?

[mangle]

Just returned from my first 500 miler pulling a 13k pound 5er. Kind-of my check out drive with this new rig.

All worked great except turbo boost is less than 10 lbs when I need it the most on big grades or passing. What gives? If I run empty, and put my foot into it, no problem, the turbo spools up showing 20 lbs on the boost gauge. Once I am pulling the rig, no such fun. I have varied the RPM, from 1200 to 2800, gear selection from 3 to 6th, and my speed from 35 to 60 mph.

Notes: this is a new “California” HO, with 3:54 gearing.

Any help is appreciated.
mangles@pacbell.net


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2001 Ram 3500 Cummings, 6-speed, 4x2 Longbed Cowboy Cadillac with B&D brake, etc.

 

[Blkdawdg]

You will always get the most boost in sixth gear. I would say to check all of the connections between the turbo and the intake plenum. But if you are already getting 20 psi then that shouldn't be the problem. If you're only getting 10 psi going up hills then I would say (1) put more foot into it, (2) get a boost module so that your boost can go upwards of 25 psi. Good luck in whatever you find.

 

[mangle]

Thanks for the prompt reply.
I have found that the engine RPM will not increase as I am under max load. Since the RPM won't increase I assume the turbo won't/can't spool up; hence I am unable to increase boost. If this is correct, one would never be able to increase boost except when not under load. This would be stupid, as the reason for having the turbo is to provide additional boost for MORE POWER under load.

Any one else with additional ideas?



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2001 Ram 3500 Cummings, 6-speed, 4x2 Longbed Cowboy Cadillac with B&D brake, etc.

 

[Ranger Dick]

Mangles, If you cannot increase engine speed for the given load, you are lugging the engine. Lugging is not good for the ISB, I think that there is a thread in www.dodgeram.org. It says basically, that if you have your foot in it for longer then one minute and are not accelerating, that potential engine damage may occur. I believe that it involves excessive vibration and strain on the engine. Best bet is to down shift, or BOMB!!!!!. Welcome aboard

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01. 5 ETH/DEE QC, 2500 4X4, 3. 54 Everything but leather

 

[mangle]

Agreed. Hence, I tested this in the lower gears, which I had to do before I came to a stand still.

When starting to climb the grades in 6th, RPM at 60mph was 1600/1700 and max boost was 5-10. When down shifting RPM would climb say 500/600 for each gear, but boost never exceeded 10. At 2800 RPM, in 3rd gear, at 35/40mph, boost remained under 10.

As for lugging, you are right. So far I have found this rig's sweet spot is 1600/1700 on flat and small grades. But seems to have a problem coming to life on steeper grades regardless of gear or RPM.

I seem to be running out of gears. Came up Cuesta grade on Highway 101 yesterday at 35 mph in 3rd. Dam chevy passed me. But, he wasn't towing. Didn't see 20 lbs of boost again until an hour of so later after stopping for a rest in which the EGT dropped from 600 to 400.

Yes, BOMBing may be the answer!!!!!.

thanks again for replying. It's a good truck - May be it just needs a good driver.




[This message has been edited by mangles (edited 04-22-2001). ]

 

[SmokinJoe]

Originally posted by mangles:
When starting to climb the grades in 6th, RPM at 60mph was 1600/1700 and max boost was 5-10. When down shifting RPM would climb say 500/600 for each gear, but boost never exceeded 10.

I towed a 2000lb two axle car hauler with a 2900 lb car. At 50 mpg going up a grade my etc/5 speed ran out of poop. Would not speed up. I do not have my boost gauge hooked up yet, but I surmise that it was low boost. The computer controls the wastegate, thus it controls the boost. This might be a brakein stupid trick from DC. FWIW I hope it goes away!

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2001. 5 QC 2500 White Sport 4x4 LWB ETC 5-Speed Anti-Spin 3. 54 Trailer Tow 241HD SLT+ Tan Leather(Mad Cow Disease) LT265/75R16E

 

[mangle]

Thanks Smokin Joe, now I know I am not the only one to experience this.

I will be speaking with my DC service department on Monday. If they are doing "something" for break-in, they should advise new owners. I wonder if there is a simple wastegate test. As I mentioned in my first post, I only fail to get full boost when hauling my heavy 5er.

[/B][/QUOTE]



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2001 Ram 3500 Cummings, 6-speed, 4x2 Longbed Cowboy Cadillac with B&D brake, etc.

 

[mike r]

You need to talk to someone because I tend to think it's computer related. Mine needed a reflash about 5 months ago and it was fine after that. That is til the bomb hit. #ad


d

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'99 QC SB White/Agate Auto 3. 54's Mustang Bed Cover, Bed Liner,BD PNP, 4" ex, 275 injectors, ISSPRO PYRO/BOOST A-Pillar,LOUD JVC CD, boost module and elbow coming soon. transmission upgrades needed soon

 

[SmokinJoe]

Originally posted by mangles:
Thanks Smokin Joe, now I know I am not the only one to experience this.

I was reading here tonight on the TDR that if you reach overboost it will run a lower boost level! If you hit that then you will have a fault code and once cleared you will have max boost when pulling again. For this reason I wish they would have kept the motor all mechanical like the 12 valvers... #ad




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2001. 5 QC 2500 White Sport 4x4 LWB ETC 5-Speed Anti-Spin 3. 54 Trailer Tow 241HD SLT+ Tan Leather(Mad Cow Disease) LT265/75R16E

 

[mangle]

Joe, this would explain why I had full boost later after a rest break. Perhaps "this" error is cleared with an engine restart.

Do you recall the TDR post?

thanks,
mangles



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2001 Ram 3500 Cummings, 6-speed, 4x2 Longbed Cowboy Cadillac with B&D brake, etc.

 

[Brandon]

contact almost any ramrunners, there are tons of local guys that can help
Brandon

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Danelle's Dodge

 

[OO]

Could be as simple as a bad map sensor. You should bea able to get 19+psi under load from 1500rpm to redline.

 

[SmokinJoe]

Originally posted by mangles:
Do you recall the TDR post?

I will try to find it tonight.


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2001. 5 QC 2500 White Sport 4x4 LWB ETC 5-Speed Anti-Spin 3. 54 Trailer Tow 241HD SLT+ Tan Leather(Mad Cow Disease) LT265/75R16E

 

[Royal]

Mangles; do you have a EGT gauge?If you lug it with low boost you should have high EGT. If
EGT is normal,you probably are not geting enough fuel. You should have boost & egt readings to trouble shoot this problem.

 

[Diesel Freak]

there is definately something causing your truck to de-fuel. when my truck was stock all I had to do to get 10 psi of boost was breathe on the go pedal. I once pulled 14K lbs over Cabbage hill here in Or (long steep winding part of I-84) in 5th (had to shift down due to EGT at 1100). it was 104F outside and I was running at 2000 rpm, 15 psi of boost and 900F EGT (pre turbo). Do not lug the cummins, it is happiest at 2000 rpm while loaded.

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2001 ETH-DEE, Diablo Power Puck, Bosch 275's, Practical Solutions Boost Module and Elbow, LFT Silencer Ring Eliminator, K&N, Straight Piped http://www.mudrunner.sites.cc

 

[mangle]

So far, my high EGT has been 700 degrees at 2500 RPM in 3rd gear at perhaps 40 MPH with 10 lbs of boost.

Today I hauled my 5er to Gilroy, mostly flat roads, some little hills, traveled at 60 to 65 MPH in 6th gear at 8 lbs boost, was able to get to 20 lbs boost by putting the pedal to the floor without delay.

It's looking like my problem (my wife tells me there are many) occurs when I climb steep grades working my way from 6th to 3rd. In doing so I take the RPM from 1600 to 2800, but never get boost higher than 10lbs.

Spoke to Stevens Creek Dodge today. The service rep told me he didn't know the Cummins engine but would investigate and call me back... still waiting.

cheers to all, thanks for the help,
mangles



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2001 Ram 3500 Cummings, 6-speed, 4x2 Longbed Cowboy Cadillac with B&D brake, etc.

 

[mangle]

Amianthus, thanks for the post to my problem. I believe you are dead on. I can obtain full fueling to achieve 20 pounds boost unloaded because the engine does not need as much fuel to hit 20 pounds boost as when I am loaded.

I have no idea how much full is needed to obtain 20 pounds boost when the truck is pulling my 5er, but considering my normal fuel mileage is half, I will assume I need at least twice the fuel as when not loaded.

Now I have to get DC to start checking and replacing. To bad my DC dealer doesn't have a tractor pull pit. It would be a great test area.

To all, thanks for the posting. I will be taking my rig to the DC dealer along with your replies to this problem.

mangles

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2001 Ram 3500 Cummings, 6-speed, 4x2 Longbed Cowboy Cadillac with B&D brake, etc.

 

[Amianthus]

First off, the wastegate is not controlled by the computer. It is mechanically operated. Second, under load, you should be able to make 20psi boost and keep it there until the engine catches up or until the maximum fueling is reached. The computer will allow you to fuel the engine up to 20 psi. After that it holds fueling steady so as not to exceed 20 psi. But will increase fueling to maintain 20 psi (clear as mud?). If you overboost, it will defuel.
As far as a solution to your problem, I would check your hose connections and your air filter. If they are okay, next I would be suspect of the computer or the programming therein. Lastly, I might suspect a bad MAP sensor, a bad TPS, or bad wastegate (although I think that is unlikely). What I can say for sure is that you should be able to make more power than it appears you are making now. Hope this gives some direction.

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'99 2500 ISB QC SLT (No Leather!), 4x4, 5sp w/McLeod, 4:10, BD-II, PE, PE-EZ, 4"exh. , Pac-Brake, A-Pillar gauge pod w/boost and pyro, Line-X, V-1, lights, siren, lic. plt. frame says "Diesel Fumes Make Me Horny!", and much more goofy stuff.

 

[mangle]

OK, I took my rig to the dealer. They told me nothing was wrong, no DTC's set, etc. No surprise, as the problem only happens under big load.

I an sure the problem relates to fuel delivery. My Thanks to all of you for advise and those that provided other bits of insight. Steve Earp made the simple suggestion of changing the fuel filter. Must remember KISS.

Cummings says my rig has a problem and I should be able to obtain 20 lbs of boost no matter what my load. My dealer says different. But after call the Dodge customer service line, the dealer has agreed to install a copilot to capture engine parameters next time.

cheers to all


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Mike Angles -- email address removed -- www.mangles.net 2001 Ram 3500 Cummings, 6-speed, 4x2 Longbed Cowboy Cadillac with B&D brake, etc. Gotta get a gun rack...

 

[C1B1DIESEL]

I would check your fuel pressure, stay above 10psi under load, also check for restriction to lift pump, 4 inches max restriction. maybe dc left the little red plug on the vent tube of the fuel tank.