Need Help With CR injector Diagnosis

[petersonj]

A friend of mine is the second owner of a 2007 Cummins 2500 truck, 4x4, auto transmission, - all stock parts. He purchased the truck in January of 2013 with 104,000 miles on the odometer. The odometer currently reads 205,000 miles. A tuner has been disconnected from the engine for troubleshooting purposes. Until recently, the truck has started and ran well. I am trying to assist him to diagnose the following problem.

In early December, he notified me that the truck started to run very poorly just as he was arriving home. He recorded these codes:

P0205 Fuel Injector 5 Circuit

P2149 Fuel Injector Group 2 Supply Voltage Circuit

Using a multi-meter he checked the resistance of all six injector solenoids for comparison. All were normal except for cylinder #5 which showed a high resistance.

On December 15th he replaced that injector solenoid with a new Bocsh unit. After the repair was completed the engine would crank over, but would not start. He said the starter seemed to be cranking at the normal speed.

On December 17th he was able to get back to the project. He primed the fuel system with the lift pump using the “bump the starter” technique for about 25 seconds. With battery jumper cables hooked up from another vehicle the engine started quickly and ran smoothly. All seemed well. He drove the truck for about 15 miles over the next couple of days.

It is a couple of days later and he notifies me and says that “check gauges” light came on and the engine oil pressure was reading very low. He checked the oil level and found that it was way over the full mark.

At this point I recommended to not drive the truck and I would come over to his house and assist. I checked the engine oil level – it was very high and diluted with fuel. I removed #5 injector solenoid to inspect the two o-rings. The one on the injector looked like it had a possible tear, so I installed a new one. The o-ring in the nut looked fine. I re-installed the injector solenoid and placed the valve cover on loosely, started the engine, and then shut it off about a minute later. I then removed the valve cover and restarted the engine to check for possible fuel leaks. Right away I noticed fuel coming out of the top of #5 injector solenoid. I realized then that the ball and set screw must be missing.

Since my friend had already discarded the old injector solenoid, I removed #1 injector solenoid and removed the set screw and ball for a sample. We went to the hardware store and with luck we were able to identically match both the ball and set screw.

We put everything back together and went to start the engine. The engine would crank, but not start (just like a few days before). Except, this time after many, many attempts it will not fire at all. We have now hooked up a battery charger to maintain the charge.

A few minutes later I crank the starter for a longer period of time and the engine catches, but only on one cylinder and is detonating as if the timing was extremely advanced. I release the key and the engine continues to barely run in this manner. A few seconds later I turn off the key because none of the other cylinders are picking up. During the time the engine was running, heavy white smoke was coming out of the exhaust.

A few seconds later I crank the engine, but no fire at all – just like before. I do a few more short starting attempts and have the same result – no fire on any cylinders. I am beginning to wonder if there is an injector leaking fuel into a cylinder causing low rail pressure and early ignition in that cylinder.

I decide to do an experiment. I disable the grid heaters and remove a through bolt on the intake manifold so I can get close to the cylinders with a small shot of ether. The idea is to get the engine to spin faster to build rail pressure. I have my friend start spinning the starter and I give a quick shot of ether into the intake manifold. I hear the smooth clatter of all cylinders firing briefly and the engine begins run again on only one cylinder, barely carrying itself, and detonating just like before with white smoke out of the exhaust.

At this point I am stumped. I am having trouble believing that replacing an injector solenoid would cause this symptom, especially after the truck ran fine for a couple of days despite the internal fuel leak.

Is it possible for an injector to have been leaking a small quantity of fuel into the cylinder for awhile (even before the injector solenoid replacement) and is now showing its ugly head?

I don’t have any access to the necessary test equipment to perform some of the tests that will probably be recommended on this forum. I would just like to hear from anyone who might be able to tell me if I am on the right track, or anyone who could get me started on the right track.

My friend just called me and said he just read the codes with his newly purchased scanner. The only codes currently displayed are P0201 through P0206 (Fuel injector 1-6 Circuit) and the code for the disconnected intake heaters.

I apologize for the long post, but I did not want to leave out any information that could help.

Thank you in advance,

- John

 

[cerberusiam]

Take out the injector you molested and get another one, it is junk. You cannot simply take these injectors apart and replace parts like that.

Whether that is the one that is causing the fuel dilution is a question, maybe or maybe another one. Likely the reason for the no start right now, probably the leak if it was missing parts.

At that mileage replace the whole set as the whole set is suspect.

 

[petersonj]

Take out the injector you molested and get another one, it is junk. You cannot simply take these injectors apart and replace parts like that.

Do you mean that an injector solenoid should never be replaced without replacing the injector?

Whether that is the one that is causing the fuel dilution is a question, maybe or maybe another one. Likely the reason for the no start right now, probably the leak if it was missing parts.

The #5 injector solenoid was for sure the cause of the fuel dilution as the new Bosch injector solenoid was installed by the owner without the ball and set screw. But, the engine ran smoothly and the truck was driven about 15 miles without performance problems while leaking fuel out of the top of the solenoid. When I stepped in to help I witnessed the fuel coming out of the top of the replaced #5 injector solenoid. Even under those conditions the engine was started twice and ran smoothly with (I am assuming) return fuel coming out of the top of the solenoid. The ball and set screw have now been replaced, so I am confident that the fuel dilution problem is resolved.

My question now, is that injector or another injector continuously leaking a small amount of fuel into the combustion chamber? Because, what else would cause the engine to not fire on any cylinders and barely run only on one cylinder with heavy detonation and heavy white smoke?

At that mileage replace the whole set as the whole set is suspect.

Most likely I am going to recommend replacing all injectors with new Bosch units, but in the meantime I really want to understand what is going on.

I do appreciate your response.

- John

 

[Ozymandias]

I'm pretty sure it wasn't a new Bosch Injector because they do not forget parts at the assembly line - never ever.
And no one without the proper -expensive- equipment and training should ever try to work on an injector assembly, those parts are damn close to rocket science.
We sure replace the whole injector, thats possible by the manual, but to disassemble the injector itself and replace parts, no no.

 

[petersonj]

I'm pretty sure it wasn't a new Bosch Injector because they do not forget parts at the assembly line - never ever.

It was not an injector that was replaced - it was an injector solenoid and I am very certain it is a Bosch. It was purchased from Diesel Fuel Injection in Portland, Oregon. The new solenoid does not come with the ball and set screw - you have to use the ball and set screw from the old injector solenoid. This company has a very good reputation.

And no one without the proper -expensive- equipment and training should ever try to work on an injector assembly, those parts are damn close to rocket science.
We sure replace the whole injector, thats possible by the manual, but to disassemble the injector itself and replace parts, no no.

I appreciate what you are saying but I am still hoping someone can answer my question regarding the engine running on one cylinder, detonating as if under extremely advanced timing and blowing white smoke while no other cylinders are firing. To me, this sounds like one injector is leaking fuel into the cylinder and when enough fuel is collected, that cylinder begins firing way early because that fuel should not be there. Can you or anyone concur with or dispute my thoughts with an explanation? or tell me I am way off base?

Thank you,

- John

 

[cerberusiam]

Yes, if you have one cylinder taking all the rail pressure the others are likely firing, just in a much diminished mode.

Installation and setup of the solenoid is part of the injector setup and calibration, don't do it correctly and you have a paper weight.

 

[petersonj]

Thank you,

- John

 

[petersonj]

Just wanted to follow up on this topic. I was able to use a Smarty Touch programmer to read actual fuel rail pressure and the truck owner purchased a block-off tool.

With all six injector fuel lines connected, the rail pressure maintained about 900 psi while cranking. With cylinder #1 injector line removed and rail plugged, fuel pressure immediately responded to above 5,000 psi and engine started and continued running on the five remaining cylinders. Fuel pressure remained steady at just above 6,000 psi at idle and responded as commanded under acceleration.

Engine oil and filter have been changed twice since fuel dilution problem. Number one cylinder injector has been replaced with a new Bosch injector and the truck is running normal with normal rail pressure readings. A lengthy test drive was performed and power is normal and smooth. There appears to be no smoke or engine blow-by or unusual engine noises. The truck owner will monitor the engine oil for fuel dilution, oil consumption, blow-by, and performance for the next few weeks. If all is well, he will be installing five more new Bosch injectors and keeping the truck.

- John

 

[sag2]

Glad it is running again, but the description does not make logical sense. If he only touched #5 it seems odd that #1 suddenly failed and you have an electrical code for the others. I was going to ask if you changed the oil after getting the new ball in #5. With heavily diluted oil the compression could be down significantly causing the hard/no start and the white smoke.

 

[petersonj]

If he only touched #5 it seems odd that #1 suddenly failed and you have an electrical code for the others. I was going to ask if you changed the oil after getting the new ball in #5. With heavily diluted oil the compression could be down significantly causing the hard/no start and the white smoke.

I appreciate your response. A couple of clarifications. I realized later that the codes were set because during the troubleshooting process the engine was cranked once with both electrical connectors disconnected. It wasn't until later that I figured that out. The codes were cleared and stayed cleared, so there were never any new codes displayed during the rest of the diagnostics. Then engine oil was changed twice before the truck was ever moved.

If you read through the details of the first post, you will see that I really made an effort to describe each event in an accurate chronological order. You will see that at one point the solenoid was removed from #1 injector to get a sample of the missing ball and set screw on #5 injector solenoid. After getting the sample, the same solenoid was returned to #1 injector. Number 5 injector got the replaced solenoid with the hardware store ball and set screw. Ironically, #5 injector never was a problem after that.

From that point on, I believe no injectors would fire because fuel pressure was so low that the ECM would not give the command to fire any injector and rightfully so. At this time I had no way to monitor fuel pressure. The reason I came to the conclusion that there was a leaking injector is because on one extended cranking period, the engine fired and barely continued to run on one cylinder with the assistance of the starter. The very harsh detonation and heavy white smoke clearly indicated there had to be fuel leaking into one cylinder (not sure which one at the time) because none of the injectors were being fired by the ECM.

So, in the end using the Smarty Touch to read rail pressure and using the block-off tool, the leaking injector was easy to find. Did I create the problem when I removed and re-installed the #1 injector solenoid? Could be. On the other hand, if that were true, why didn't the engine start for the one day before #1 injector solenoid was even touched?

This engine has 205,000 miles on the odometer so it is reasonable to consider that any injector could have been leaking into a cylinder before the issue with the #5 injector solenoid open circuit even occurred. This has been a learning experience for me.

I communicated with the truck owner today and so far so good. If the truck doesn't exhibit any engine problems over the next few weeks, then the engine will get the other five new Bosch injectors.

- John