1999 Frieghtliner Rollback with 5.9 24v Cummins

[ablokzyl]

I am working on a 1999 Frieghtliner with a 5.9 24v Cummins with a build date on the cab of 4-98. I'm not really familiar with the Cummins engines but I took the job anyway. The problem I am having is very low power. It will just barely make it over 30mph. After the engine warms up (after approx 30 min) it runs decent but still not as good as I think it should run. I checked the fuel pressure after the lift pump and after the filter housing.......both are 14psi. I dont have access to any info on this engine other than Alldata, but I have to look it up for a Dodge 3500. The fuel pressure specs in alldata are either 10psi minimum for one engine or 25-30psi for the other engine. I was wondering if anyone knew the pressure specs. I dont know where else to look.......Thanks

[ablokzyl]

I forgot to mention that a Frieghtliner dealer already installed a new injection pump and a new ECU. They said that the next step was to throw a wastegate at it but I thought a little diagnosis would be the better step. Thanks again

[OHNO60]

sure ab. give me the engine serial number.

[ablokzyl]

I looked for the serial number last night but had no luck. The only serial number I can find is on the tag on the new ECU. Is that the number or is it somewhere else?

[LARRY BRUDZYNSKI]

p/m me the last 6 of the vin and I can get the esn for you. Just off hand did you check the fuel return check valve?? Sometimes they get buggered up. Is it throwing any codes??

[LARRY BRUDZYNSKI]

Got the esn# for you. It's a ISB 5.9 ESN 56443304

Do you have the insite software to hookup to the truck?

[ablokzyl]

No I dont have access to that software. All I have access to is Alldata and the normal Ford dealer tools. We are not a heavy truck shop. I am trying to do a buddy a favor by working on this for him.

[LARRY BRUDZYNSKI]

What codes are you able to get?

[ablokzyl]

I held the "engine check" button on the dash and got flash code 433 and 382

[ablokzyl]

I think I might have found the problem. If I pull the hose off the wastegate, I can blow directly through it. Shouldn't the diaphragm inside the wastegate hold pressure?

[LARRY BRUDZYNSKI]

Are you checking the wastegate actuator at the actuator or thru the hose? Use a mity-vac at the actuator it should hold vacumm. If not it is bad. Make sure you check the wastegate hose and line for cracks or corrosion it's real common problem. The part # for the new actuator kit is 4030018 priced around $180.00. Or if you need a turbo the reman # from Cummins is 3802881RX priced around $1100.00 exch. $80.00 core. I have brand new Holsets on the shelf for around $975.00 exch.

[SteveS]

We see way more Dodges than Freightliners but the 24 valve is mostly the same. I was not able to come up with an evaluation of the code numbers, I am usually stuck relying on our Modis that will get the description with the code. But let's see what we can come up with.

 

The fuel pressure sounds OK for now. I like to check it on the road and have it not go below 5 psi on full load on the injection pump side of the filter. The 12 valve is the one that should have the higher pressure. The electric lift pump on the side of the engine is not very reliable, but it sounds like yours is working. Later when the engine can work at full, normal power you should recheck the loaded pressure. If the engine runs long enough with low pressure it will kill the VP44 injection pump.

 

The wastegate actuator should hold pressure but it won't cause the massive loss of power that you have. If the engine was running correctly then it would over-boost because the actuator is not holding enough pressure to operate; that might be one of your codes. As it is now there is not enough boost loss to make a difference, but my gut feeling is that the MAP sensor is going bad and if the ECM doesn't see any boost then it won't increase the fuel under load. I'll see what I can dig up for testing with no data stream, it will probably be a voltage measurement as you supply regulated air.

 

It hasn't blown off a boost hose, has it? No excess play in the turbo shaft or blades touching the housing?

[ablokzyl]

I checked the wastegate actuator hose for cracks and there are none. I can blow directly through the actuator nipple itself. It hasnt blown any boost hoses off. I found a place on the net that has the code definitions. 433 is "Intake manifold pressure ckt" and 382 is "Intake air heater relay ckt". I found the reason behind the intake air heater ckt code.......there was a broken wire to one of the intake air heater relays. I repaired the wire and the code went away so that tells me that these are hardfault codes. I was trying to find the manifold pressure sensor, but the only sensor that i can find near anything that would have intake pressure is a three wire sensor at the back side of the intake manifold. It kinda looks like a coolant temp sensor to me though. And the turbo dosent have any play or fins are not hitting the housing.

[LARRY BRUDZYNSKI]

I believe that the coolant and intake sensors are the same on the ISB's they use the same one in both places. On another thought has the update for the oil pressure sensor been done yet. They had problems with the 2 wire sensor and changed it over to a 1 wire switch. It would get false low oil pressure readings and send the vehicles into a derate. Cummins came out with this fix which needs to be done at a Cummins dealer or Distributor. Check the oil sensor how many wires does it have?

[SteveS]

Good, one down and one to go.

 

The MAP sensor is on the side of the head toward the back. It should have 3 wires, I believe that it will have the connector style with one wire over 2 wires, sort of configured like a triangle and a large hex body (1 1/4" as I recall) but the replacement might be smaller in the hex area.

 

It is a typical sensor with 5 volt ref, sensor ground and signal. I am relying on a Dodge diagram, so the colors are not right but the 5v circuit is pin A (Orange), sensor ground is pin B (Blk/Blu) and signal is pin C (Gry/Red). It should be that if you look at the wire side of the connector and had the part with 2 pins on the top that A would be on the left, B on the right and C on the bottom. I don't have a sensor chart in front of me but would guess that no pressure should be 0.5v and 25 psi would be over 4 volts. I am not sure where the overboost code threshold is in voltage, in a pickup it is 22 psi.

[SteveS]

I believe that the coolant and intake sensors are the same on the ISB's they use the same one in both places.

That is probably true of the IAT but not the MAP. I think that it will defuel if it thinks that the intake charge is too hot, but I have not ever known of a problem in that direction.

 

BTW, I have a motorhome in right now on which the ground for the intake heater burned off. I haven't yet figured out what caused it to stay on, I think that the relay(s) stuck on, but we lucked out that the heating grid didn't break apart and go through the motor. If you suspect that the intake heater might be staying on too long it would be better to keep it unplugged than to burn it up.

[ablokzyl]

I dont have any reason to think that the intake air heater is staying on. I cannot find the map sensor. Could someone tell me where it is? Thanks

[SteveS]

It should be near the back of the driver side of the head. As I recall the IAT (2 wires) is the rearmost, MAP (3 wires) is second from the rear. The intake "manifold" is mostly in the head casting, so look a little below the top manifold plate. I had a page from Mitchell illustrating where it is on a pickup but we've been having some problems getting things to print. The reference that you were using for Dodge info might have a picture?

[LARRY BRUDZYNSKI]

???? I might be wrong.... But I don't think a Freight-shaker has a map sensor???? I'll check it out on Tues. Sorry Canadien dudes we have Monday off!!!!

[SteveS]

I will be near work tomorrow, I'll stop in and see if that motorhome (Freightliner chassis) has a MAP. I am 98% sure they all have it on the 24 valves but am willing to consider that I have not seen it all.

 

I don't think that you need to apologize to Canadians about a holiday; they seem to have more than our government employees!!! /forums/images/%%GRAEMLIN_URL%%/wink.gif

[SteveS]

Well, I thought that I was going to need something from the equipment rental shop but I got by without going into town (burning stumps is my pre-summer project over the last few weekends).

 

Did you find the MAP?

[ablokzyl]

Yes I did find the Map sensor. Tomorrow Im gonna get my DVOM from the shop and see if I can't diag a little further. Thanks

[SteveS]

I borrowed a Cummins book from a friend, it has 8 pages with illustrations on the 433 code. It is a "Light Duty" spec book, so a lot of it is for Dodge applications, and they cross that code to P0236. It is a bit much for me to copy manually but I'd be glad to scan it and send it to your email address if you want it.

[ablokzyl]

Yeah that would be great. My e-mail address is viper_ab@hotmail.com thanks

[LARRY BRUDZYNSKI]

Something doesn't seem right, I don't think your looking at the map sensor. It seems like its derating to me.