I got a customer with a d6r that I’ve worked for before changed a few sensors here and there but have ran into a diagnostic problem. It had a 164 code about a year ago and it ended up being the iap sensor. problem was that it wouldn’t start when hot changed the sensor and it started when hot and was working good for about 100-200 hours (farmer owned machine doesn’t get used lots) I get a call saying that it’s doing the same thing again. so the day I go out to check it out he calls me saying now it starts good hot but has trouble starting cold(Excessive cranking) active code displays 164.04 when engine off key on and when it’s running the code is not active. It has 164.11 all the time not active. I checked wiring briefly. Never load tested wires but I unplugged the sensor and shorted the connector and got the 164.03 to change to 164.04 which I figured the ecm/harness was working the way it should. Also getting 5v to the connector. I didn’t back probe while plugged in to see but that’s what I checked. The ecm was changed about 10 years ago on that cat. I also did a injection actuation pressure test. It wouldn’t meet demand at about halfway to max pressure but if I revved engine up it would meet or be close. Are those tests supposed to be just idling? I got a new sensor and plugged it in to the cat but not into the engine and the 164.04 code is still active so was thinking maybe load test wires or possible ecm? But judging from the injection pressure actual not meeting desired when it’s stepped up to about half of its max(can’t remember what pressure exactly it failed to meet) that maybe injection o-rings or possible heui pump. Any help here would be appreciated. Thanks
To get help requires a machine Serial Number for a start, especially for a D6R where there are apparently a gazillion different models. It's always nice to know what we're dealing with and additionally it makes it easier to look up technical information.
Serial number is ADE00711
So first up the Active 164-04 when the engine is stopped will inhibit cold mode so right there is probably the reason why it doesn't start too well when cold. I have attached the test procedure for the Code. Can you expand a little on that please. If 164-11 is Logged you should be able to erase it with ET, which from the sounds of it you have. Has that been tried and does it come back under any particular circumstances.? This particular machine was manufactured in 2004, so that poses a few questions: - How many hours are on it, specifically on the engine.? Is the HEUI Pump original.? What about the injectors.? Does the customer use good quality oil (needs to be API CH-4 or better) and good quality engine oil filters.? I know you said the machine does not work a lot of hours but does the oil get changed on a regular basis.? With low operating hours the oil & filter should really be changed every 6 months or so. Replacing all the O-Rings on the injectors might not be a bad first (and relatively inexpensive) step. If the injectors are original the seals could be pretty tired by now.
I will find out if heui pump, injectors are original. Also what kind of oil he is using and how often changing. I do remember engine oil pressure being good (I believe around 40psi). I have not tried to erase any codes but will do that next time I go out there. As far as the 164.11 code I haven’t done too much looking into that. Just figured it was showing because of the 164.04 code. The only thing I haven’t done with the test procedure on 164.04 was running new wires to the ecm, and creating a short at the ecm. I shorted the sensor connector and got my 164.04 and a 164.03 when open.
There is no relation between the two. See the attached for an explanation of the 164-11. It could well be related to the what you said regarding the big difference between Desired and Actual IAP. That's why I asked if you had tried to erase it and whether or not it came back. TBH I would do that first. This is nothing to do with oil pressure. HEUI engines are very particular about clean engine oil and because soot is a by-product of combustion the oil in a diesel engine is never particularly clean. The soot levels can be mitigated to a certain extent by using good-quality oil & filters and changing both regularly. That's why frequent oil and filter changes are essential to best keep the components of the HEUI system in good condition. Another potential clue regarding dirty oil is that you had to replace the IAP Control Valve in a previous repair.
Ok thanks for clearing that up for me. Another thing I was going to do is check to see if the pump is putting out the minimum pressure while cranking when it’s cold. I never replaced the IAP control valve. Just the IAP sensor. I didn’t think the control valve was replaceable on the c9’s. But I’ll try everything you said when I go out there next. Should be this week and I’ll get back to see if I find anything. Thanks Nige.
Hey Nige, I’m going out to that cat tomorrow and wondering about the injection actuation pressure test. Is the pressure supposed to be up to spec at idle and all running conditions? Just clarifying before I make decisions being unsure of that. Thanks
When it is cranking the engine shouldn't fire off until the Actual IAP is equal to or greater than the Desired IAP. At all times while the engine is running the AIAP should be close or equal to the DIAP, maybe even a bit above it. A good test would be to put the tractor in gear, stall it in 3rd speed against the brakes, then slowly accelerate the engine. Watch what happens to the two pressures as the engine load rises until you get to full torque converter stall. Even at full load the Actual should still equal the Desired. If it falls behind as the load increases that is an indication of something in the system is either worn or maladjusted.
Ok I will try that. When I’m on the inj pres test on et and I step it up to the max demanding pressure with the engine at idle should the actual pressure meet desired or does it need to be revved up?
I was just out there and tested some things. I pulled valve cover and cranked engine over and it was shooting oil out towards exhaust on at least 3 cylinders. Didn’t get a good look at number 6,5 or 1 i think it was more then 3 but also found out number 5 injector was changed a few years back. Also when I have key on engine off my inj act pres desired and actual are both at 2500-2600psi(I can’t remember the exact number just know it was 2500 something) it stays at that when cranking. Is that correct? I thought it should show the minimum pressure needed to start the engine which is around 870psi. I followed the diagnostic procedure for the 164.04 and I’m getting 7volts instead of 11 between pin c and a on the sensor connector. I unplugged the sensor and code changes to a .03(open) plug back in it goes to .04(short) then I disconnected ecm connectors and tested continuity from p2 pin 27 to every other pin and got open on everything like it should. Then shorted the sensor connector and it changed code to 04 from 03, I ran new wire from p2 pin 2 and 27 to the sensor connector and got no different results other then another code showed up and it was 164.00 then I unplugged my pin 2 and left 27 and it gave me every 5v sensor code. So I undid everything and put it back the way it should and I’m getting 04 code again with it plugged in. What am I missing, kind of seems like I’m overlooking something simple. The turbo inlet pressure sensor is unplugged because of the air box being out to remove valve cover. Would that have any effect on this sensor voltage? Or any other sensors effecting this one?
The actual IAP value comes from the rail pressure sensor signal. While it might not fall completely to zero with the engine stopped it should be there or thereabouts. Was it creating a Code.? Personally I would remove the sensor from the intake duct and plug it into the machine harness temporarily just to prevent a Code being created. Where does the procedure tell you to do that.? Between Pins A & C you are measuring the pull-up voltage. It says, and I quote - "Measure the voltage between terminal A (5 V analog supply) and terminal B (sensor return) at each of the sensor connectors. Expected Result: The voltage is 5.0 ± 0.2 VDC"
Sorry I meant between c and b I’m getting 7 volts. Between an and b I’m getting 5. Have a new sensor to temporarily plug in and it’s still showing same code. Shorted plug between b and c and code went from 03 to 04. I checked resistance between pin 27 on p2 and every other ecm connector on p1 and P2 and it was open on every one. I had a temporary wire going from p2 to pin c on the sensor connector and it threw every 5 volt sensor code voltage above normal. So I pulled it out and I got the 164.04 code back when everything was back how it was. Not sure what to look for next.
Instead of measuring resistance at Step 6 between Pin 27 for the IAP sensor signal and all the other wires in Connector J2 try connecting the signal wire to machine frame ground at the sensor end and then using a 5A fused test light supplied with Batt+ try each pin of J2 in turn. Sometimes a test light can give different results to a multimeter which only uses minimal current.
And if you hook up a Micro Clamp On to the wire that Nige suggested, or through the DCAmps of a multimeter it will tell if the wire has become corroded internally towards black, or if the wire is leaking voltage elsewhere. All copper wires will turn blackish and then green if in the elements or subjected to hot and cold long enough. Simon C
I will try that next time I go out. So basically if the light turns on then there is a short? Also the way the schematic looks is that that wire isn’t connected anyway to another wire so if I ran a new wire from the ecm to that connector should that not eliminate the signal wire? I also have a load pro tool for the multimeter, would that be worth a shot. Not sure how or if it works with ecms or 5v ref circuits.(I’ve never used it yet). The other way I test wires is running an incandescent light on one end of the wires and giving power and ground through the other end and checking voltage drop across the light to see if it’s taking all of the load or if there is another draw somewhere.
Do u mean micro clamp as in like an amp clamp to measure small amounts of current? I’ve never heard of a micro clamp. I can use a multimeter on the dc amp and you mean between my power source and the ecm connector wiring harness?
Another inquiry about the injector seals and hard starting. It cranks for about 20-30 seconds before it starts but I also noticed the primer pump doesn’t work. No power to it. That should turn on for 30 seconds or something when key is on correct? I’m thinking unless there is a leak then it shouldn’t be the reason why it’s hard starting correct? Another question about injector leakage since I’ve never had really anything to do with Heui system, when I checked under the valve cover I just tilted it up towards exhaust side of engine and the oil when cranking was shooting up just enough to touch the valve cover. Would that leak cause a hard start? To me it doesn’t make sense why it would but i just don’t have much heui experience.
Extech sells a very small clamp meter that will measure thousandths of an amp DC ( Model 380947 ) and I have had one for 19 years. Super handy for relays or troubleshooting stray currents. Or you can run the power source through your meter on DCAmps before going through the 60 watt-5amp bulb, then through the wire being tested back to ground. If the power consumed varies lots from the power required just to run the bulb, you will have a good idea about harness condition. If a wire pops and you see smoke you know where the problem was. Simon C
Sounds good. If the harness tests bad is there any reason that I can’t run a new wire from ecm to sensor?
Cannot think of a reason why a wire cannot be run from ECM to sensor, that being said you would have to make sure the rest of harness is not rubbed through or damaged. If the wire blew from too much current for too many years, the other wires in harness would not be far behind. Some guys have repaired and done new harness when more convenient. Test it first and find out. Simon C
Sounds good. Thanks for the help Nige and Simon
Good day, Did you get to the bottom of this Failure? As i am Having the Same trouble with a D6R Serial:S6X01514 But without having Any Fault Codes on ET, The only thing i could pick-up from ET is that the AIAP is a third of the DIAP Throughought the idle or high idle, Changed the Injectors and Pump, Double Checked the back up rings and o-rings on the Injectors, and replaced the injector loom and Sensor, Any thoughts?
Does that engine have some kind of Return fuel regulator or check valves. Maybe someone else will chime in with a diagram or test pressure. Simon C
If that was the case in theory the engine should not even start. Unless Actual IAP reaches Desired IAP during cranking the ECM should not fire the injectors. There should be an “Injection Disabled” status bar on the bottom of the ET screen until Actual IAP reaches Desired IAP, at which point it goes out and smoke should come out of the chimney. What symptoms does the engine have.? How many hours are on it.? Were the parts you installed OEM or aftermarket.? Has anyone looked at the IAP sensor.?
I never got to the bottom of the iap sensor not reading until the engine was running. The hard starting was the regulator at the back of the head. I bypassed the harness and ran new wiring to everything and it still had the code so I figured the reman ecm that was changed 10 years ago went bad again. Not worth replacing for the situation.