No start help please.

[CMORGANSKOOL]

07 Dt466e 125,000 miles. Had an intermittent stall for a couple years. Finally went to go on a trip and no start. Replaced the icp sensor and high pressure oil rail o rings and it started and ran fine again. So I went and got oil and a filter and fuel filter and air filter and did the regular maintenance. After the oil change no start. The batteries are several years old so I replaced them. When the batteries are fully charged and I turn the key I get the ecm start up as normal. When I crank I get the rpm and oil pressure for about 10 seconds and then the gauges reset and all show nothing. It did this before I changed the sensor too. After they do that they’ll do the normal ecm cycle but when you crank they show nothing. I disconnected the icp plug to see if maybe the new sensor I got was bad but still no start. What should I replace next?

[magnakansas]

Dont replace anything next.

next -- confirm if the fuel injectors are being activated by the engine computer.

If the fuel injectors are being activated, confirm you have fuel pressure to the injector. If fuel injectors are not being activated confirm you have injector firing signal from the engine computer.

work the diagnostic tree from there.

only replace parts if they are known high failure rate items and they are cheaper than spending the time to diagnose the problem.


Your description of the events would seem to indicate a problem with electrical side of things... I would be willing to bet the items you replaced have nothing to do with the cause of your problems.


william

[HamSkoolie]

Originally Posted by magnakansas

Dont replace anything next.
AND
only replace parts if they are known high failure rate items and they are cheaper than spending the time to diagnose the problem.
AND
Your description of the events would seem to indicate a problem with electrical side of things... I would be willing to bet the items you replaced have nothing to do with the cause of your problems.

william

Agree on all points!!!!!



Parts can be bad out of the box, fail shortly after being installed, or last a long time. Throwing parts at things can cause other problems when you dislodge that connector you didn't see or a myriad of other things including a bad out of the box part.

Troubleshoot based on codes and symptoms.
There was no mention of codes. Do yo have any?

[CMORGANSKOOL]

Originally Posted by HamSkoolie

Agree on all points!!!!!



Parts can be bad out of the box, fail shortly after being installed, or last a long time. Throwing parts at things can cause other problems when you dislodge that connector you didn't see or a myriad of other things including a bad out of the box part.

Troubleshoot based on codes and symptoms.
There was no mention of codes. Do yo have any?

I don’t have a code reader. No check engine light. The gauges not displaying pressure or rpm was a indicator originally of an electrical issue. Icp is a very common no start on the 04-07 Dt466e and symptoms include intermittent stall or loss of power. When I took the old sensor off it was clogged with oil gunk. While I was under the valve cover I did the high pressure oil rail o rings. When they fail they leak and also cause an intermittent loss of power and can cause a no start due to loss of pressure on the high pressure rail. The no start is almost always caused by a sensor failure. Just not sure where to go next. It’s not the icp I just replaced because it can be checked by unplugging it which gives the ecm a default valve. If it’s bad it will start with the sensor unplugged. I have fuel, fuel pressure. Fuel at the injectors. Oil, oil pressure, air. The no start manual doesn’t really give any indication of where to go. Just check and replace unit everything is new.

[magnakansas]

I would connect to number one injector signal and connect to the crankshaft position sensor... with a two channel oscilloscope, If there is no missing tooth for TDC, then also connect to cam sensor.....

Again, sounds like you are failing on the angry pixie = electrical - The oscilloscope is the fastest way I know to check. Understanding what is used for the injector trigger- crankshaft or camshaft is key for the check...

by doing this you check two things at once, first you check that the injector is being fired, and being fired at the correct time. third is the pulse width.. is the injector being fired for the correct amount of time.

I prefer to use scopes, over scan tools, scan tools can be very model specific and a scope lets me check out just about anything from points and plugs, ignition coils, abs/wheel speed sensors, vss- vehicle speed sensors, lets me watch stuff like intake manifold pressure sensors vs throttle input. just all sorts of stuff.

My best guess is your injectors are not being fired, but I want to see it in action, other, otherwise just a guess.

william

[CMORGANSKOOL]

Originally Posted by magnakansas

I would connect to number one injector signal and connect to the crankshaft position sensor... with a two channel oscilloscope, If there is no missing tooth for TDC, then also connect to cam sensor.....

Again, sounds like you are failing on the angry pixie = electrical - The oscilloscope is the fastest way I know to check. Understanding what is used for the injector trigger- crankshaft or camshaft is key for the check...

by doing this you check two things at once, first you check that the injector is being fired, and being fired at the correct time. third is the pulse width.. is the injector being fired for the correct amount of time.

I prefer to use scopes, over scan tools, scan tools can be very model specific and a scope lets me check out just about anything from points and plugs, ignition coils, abs/wheel speed sensors, vss- vehicle speed sensors, lets me watch stuff like intake manifold pressure sensors vs throttle input. just all sorts of stuff.

My best guess is your injectors are not being fired, but I want to see it in action, other, otherwise just a guess.

william

The injectors are definitely not firing in a no start. The problem with these ecm 466 is if any of several sensors connected to the ecm fail the icm will not activate the injectors. I pulled out the service manual and started going through it. There’s a logical progression to the diagnostic but it involves going through and replacing everything. I ordered a new ipr sensor and cam position sensor. I’m going to go through and see if can check continuity on some before replacing. They’re expensive. The ipr was $200. I think it’s a couple thousand to replace all the sensors. It’s probably cheaper to replace the whole motor with a mechanical model.

[magnakansas]

that is why I like just using an oscilloscope.... prefer quad trace.. lets me look at several signals at once and I dont have to bide that silly replace the items thing... I can see the signals... also might keep a trace for power right at the ecu and see if you are dropping a power to the ecu... there is just some much to check.. one step at a time

[CMORGANSKOOL]

Today I checked the idm and ecm fuses and relays. I checked all the wiring harness connectors. Checked the ecm power connector at the batteries. Rechecked the fuel system. No start.

[CMORGANSKOOL]

Ok with the help of Joe’s bus barn I ran down some more stuff. So far I’ve replaced the icp, oil rail o rings, ipr sensor. I’ve checked and cleaned the battery terminal ring connectors, the ecm fuses at the battery box. The 3 pin ecm connector at the battery box and the ecm ground at the battery box. I’ve cleaned and checked the connector by the starter, the harness connector and pin 9 on the round harness connector. I’ve replaced the ecm and idm relays. Checked that I have voltage at the relays. Replaced both batteries. Checked voltage at the icp connector. Still no start. The remaining systems to check are he hpop for pressure and the ecm and idm connectors for connection and cable continuity. I’m sending it to the shop to have that done.