I recently had my truck in the shop for some minor repair. '99 Dodge Quad, 3/4, 4x4, 24V, 5-spd, 285 tires, 103K miles, 15 mpg at 65, 355 rear, everything stock.<br><br>While it was there I had them check my lift pump:<br> Idle: 11psi<br> WOT: 9psi<br> Full Load: 5-6psi<br>I know these are low but looking at some posts here I'd be gambling to get any better with a replacement.<br><br>BUT I was more concerned when they told me I had only &gt;&gt; 2 PSI &lt;&lt; coming out of my turbo! This may explain why I can barely hear any whistlin under the hood gettin on it.<br><br>These codes were retrieved with their scan device:<br>P0236 - Turbocharger Boost Sensor A Circuit Range/Performance<br>P0382 - Exhaust Gas Re-circulation Flow Malfunction<br>P1693 - Turbo Charge Control Circuit Malfunction<br><br>The mechanic who test drove my truck did said it seems low on power. I do notice a 1 or 2 mph speed decrease up a big hill for a couple of seconds with no load but it does recover.<br><br>Should I make the homemade device found under “Tech Facts” that will allow me to pressure check my turbo for leaks - and/or look for turbo related sensors to replace them?<br><br>Since I got the truck I have:<br>- Replaced my IAT (wow what a difference) and MAP sensors<br>- New Fuel Filter<br>- New wix air filter in stock box<br>- Removed the Vent Cap from my fuel tank left by factory!!<br>( Runs a LOT smoother but still have the same power and 15 mpg )<br><br>Thanks in advance for your input. This is a great board and I've learned a lot so far.<br><br>ps. Just kidding about the Slick50... I do hear they make a Big Rig formula though.

 

Sounds like your wastegate may be stuck in the open position just a little or you are losing pressure through your &quot;plumbing&quot; from the turbo to the intake.<br><br>First tighten all the clamps, starting at the turbo, through the intercooler and up to the intake air plenum. Then, use a torque wrench and do the air intake plenum (4 bolts) torquing to 18 ft/lbs. Go ahead and do the top of the intake manifold while you are at it.<br><br>I'm curious as to how they arrived at the 2 psi number. Did they put a guage on it?<br><br>The control circuit for that is the MAP sensor. If it is bad, you could be limited to the amount of fuel used at 2 psi boost. That could be why the turbo doesn't seem to be &quot;spinning up&quot; for you.<br><br>Finally, make sure you have a fresh fuel filter in there. A dirty filter can reduce available fuel and cause poor mileage/performance like you are experiencing.

 

I'd look into the MAP connector to make shure that it's good- maybe test a MAP sensor from another truck.(or the old one)<br>REset the codes and try- I do not know about the EGR....<br>You could try to apply pressure to the wastegate actuator and see if it moves ( Don't have my manual at hand but the pressure is rather low)<br><br>HTH<br><br>AlpineRAM

 

To answer your question about Slick50, I wouldn't. If after you find the real problem such as the wastegate, loose clamps, etc. as mentioned above, and want a little quicker spool up, go with either Prolong or Militec1. Any of these will require routine additional treatments.

 

Just wondering why you waited until 103K miles to take it in? All of this would of been covered under warranty at 99,999 miles ???

 

[quote author=steveb link=board=4;threadid=14116;start=0#132667 date=1051503523]<br><br>I know these are low but looking at some posts here I'd be gambling to get any better with a replacement.<br><br>BUT I was more concerned when they told me I had only &gt;&gt; 2 PSI &lt;&lt; coming out of my turbo! This may explain why I can barely hear any whistlin under the hood gettin on it.<br><br>I do notice a 1 or 2 mph speed decrease up a big hill for a couple of seconds with no load but it does recover.[/quote]<br><br>Your Fuel pressure is pefectly fine for a stock truck.<br><br>1 or 2 MPH decrease going up a hill? Is that WOT?<br>My truck does that occasionally, but it sets a check engine light and codes for low boost (MAP Sensor), after a little while of WOT power picks up a bit nearly instant ~20+HP.<br><br> <br>2 pounds of boost? Something is definatly wrong, (if not MAP, even a New MAP could have bad connections, or just be bad), you should see about 18-20PSI at the turbo outlet (going into the intercooler) and 16-18 in the intake plenum (That's that big silvery thing after the intercooler, and mounts right on top of the grid heaters)<br>You may have a messed up turbo, stuck wastegate, or an extreme boost leak. But with a boost leak and stuck wastegate, you could hear the turbo whine a little bit,, but a bad turbo any turbo whine would be near non-exsistant.<br><br><br>If you DO have a bad turbo,, please, please, please don't buy a stock replacement turbo. Unless $$ is real tight, then it is okay. <br><br>Let us now what you find out after you check the wastegate, inter-cooler boots, and see if the turbo bearings have any excessive play. <br><br>Hope this Helps,<br>Merrick Cumming Jr

 

Anything below 8 psi on fuel pressure and it's replacement time. :'( The low fuel pressure can play a factor in poor fuel mileage, but not always. If you do not have a gauge (you really should) you'd be irresponsible to leave that lift pump on there if for no other reason than new injector pumps cost around 1500.00, and if you had that kind of money laying around you would already have the new lift pump on there. Please remember the lift pump supplies the fuel that lubricates and cools the injector pump. This means that if you do not have enough fuell going through that pump you are slowly killing it.

How did they check the boost? If they didn't check it going down the road then the test is no good. You get no boost until you get the RPMs up and get a load on the engine, unless you've disabled the wastegate ;D and have extra fuel goin in there.
And if your turbo wasn't working you should be SERIOUSLY low on power. There'd be no question about it. See if you can drop a few bucks on a boost gauge then you'll always know.

As far as additives go, 99.9% of their claims are BS and Cummins recommends NOT using any kind of additive in the engine.

Chris

 

[quote author=Stamey link=board=4;threadid=14116;start=0#133032 date=1051583563]<br>Anything below 8 psi on fuel pressure and it's replacement time. :'( <br><br>How did they check the boost? If they didn't check it going down the road then the test is no good. You get no boost until you get the RPMs up and get a load on the engine, unless you've disabled the wastegate ;D and have extra fuel goin in there. <br>[/quote]<br><br>1. I stand corrected<br><br>2. I agree.<br><br>At 3,500 RPM a stock HX-25 with the stock 12cm housing, you should make around ~5PSI..(No load)<br><br>My HX-40 w/18 housing makes about 3-4 PSI @ 3,500RPM. (No load)<br><br>Merrick Cummings Jr

 

I want to thank all of you for your very helpful information. Yall are probably going to turn me into a BOMB addict yet [eyecrazy]. I really do love my Dodge. Bumpier than my old Chevy Z but it has the power, sound and curves to make up for it! ;D<br><br><br>To be honest I'm not sure how they tested boost, therefore, I may not even have a problem with it??. This wasn't a Dodge dealer but a good diesel mechanic (big rigs) and I don’t think they have the knowledge you guys do on this specific engine. I trust them from the referrals. I did pass the information about this site to them and started talking some lingo I read about here and they actually thought I had mechanic ability - WOW. The only reason I took my truck here was because I was told to avoid the Dodge dealership at all costs...long story (5-star with a bad rep). <br><br><br>A lot of helpful posts point to my MAP sensor. Went to the Dodge dealership and grabbed one for $104.00. NO noticeable difference from my old MAP. Threw the old one in my toolbox for a rainy day along with that $36 barely suit covered IAT sensor I replaced that actually did a world of good.<br><br>While I was at Dodge I inquired about the cost of a lift pump - $230.00 +++++ GET THIS… The parts guy told me “Dodge really got strict on these pumps...I CAN’T sell them direct anymore, only a technician at a dealership can order them and perform the replacement.”<br><br><br>Anyway:<br><br>So far I’ve tightened all my clamps around the turbo and plumbing going to the intercooler. Took the turbo inlet off and inspected the turbo wheel. No oil residue turns freely, no play back/forth (Weird little burn or soot looking area at the bottom??) I removed my silencer ring while I was in there just for grins - got a little high pitch squeal now, no where near 747 turbine though.<br><br>I don’t have a torque wrench so I don’t feel comfortable doing the other things you advised Smoke Dog. I’m great at twisting off bolts. I had a bad experience under my shade tree when I stripped the spark plug on my 1965, 50 horse outboard. I’ve shy’d away from mechanics ever since.<br><br>AlpineRam – I may very well have a wastegate issue. I have no idea how to apply pressure to the wastegate though. All I can tell you is when I had the rubber inlet off the turbo intake I pushed around on it a little but it didn’t move. Of course I was pushing on the housing. I did see a small black hose there. I plan to build the homemade turbo leak pressure checker that someone posted on this site under Tech Facts. I just haven’t got around to it yet. Then, pressure check the turbo and all the plumbing for leaks with 25psi or so.<br><br><br>PitBull - I’m sure you’ve heard the quote “knowledge equals power” before. I waited because I’m a newbie, idiot to the Cummins diesel world. I don’t feel so bad because I personally don’t think the diesel mechanics at the Dodge dealership know 1/2 the things you guys do. I simply found this website and got smart 1 mile past warranty. I hope every diesel newbie reads EVERY post you pros place here before their 100K mile marker. Live and learn.<br><br><br>You guys talked me into a lift pump (along with high-flow banjo bolts). I found a Cummins dealer nearby for that part since the Dodge dealership won’t work with me. I haven’t got a price from them yet. If you guys know of a cheap Cummins dealer where I can order a lift pump online please let me know.<br><br>You’ve also talked me into the gauges. Fuel pressure for sure and boost.<br><br>These thinks will have to wait a while… short on cash.<br><br><br>Again, I’d like to thank everyone for your input. Here’s a free copy of my e-book “3 Easy Steps To Rock-Solid Virus Protection” and my “Spyware Special Report”. I’ll help you with something I DO know about - computer mechanics :)<br>http://www.antivirusebook.com/tmp/dts/index.html

 

Read THIS before you think about putting any stuff in your very expensive motor!

 

steveb: Applying some air pressure to the wastegate actuator is quite easy. You just take the black hose coming from the compressor outlet going to the wastegate actuator and apply some shop air. Be careful never to exceed 30psi! (A good pressure regulator can save you lots of headaches). You could also remove the rod from the actuator and try to move the wastegate by hand. It must move freely. Then look whether the acuator keeps it shut by alligning the head to the arm (sorry for my bad english) when there is no boost. <br>I have resolved a lot of the problems I had by cleaning and inspecting all electrical connectors that are in the engine compartment.<br><br>AlpineRAM<br>

 

[quote author=MCummings link=board=4;threadid=14116;start=0#133089 date=1051595500]<br><br>1. I stand corrected<br><br>2. I agree.<br><br>At 3,500 RPM a stock HX-25 with the stock 12cm housing, you should make around ~5PSI..(No load)<br><br>My HX-40 w/18 housing makes about 3-4 PSI @ 3,500RPM. (No load)<br><br>Merrick Cummings Jr<br>[/quote]<br><br>My stock HY35 with the 9cm wastegate clamped shut won't make any boost just free revving.

 

With your truck at operating temperature,, put your truck in park or Neutral, and go WOT and hold it there for a few seconds and you should build close to 5 PSI boost.<br><br>My truck (40/18) will build 4PSI at 3,600-3,700RPM.<br><br>With your wastegate clamped,, do you have a boost fooler of any kind?<br><br>Merrick Cummings Jr<br><br>BTW, I got your message

 

Excellent article Katoom; thanks for sharing it. It is always good to get information that has good research behind it.