my typical doulble whammy

[dripley]

Well I notice after changing my oil 2 weeks go that I had not had to add any which is unusual since I have a leaky rear main seal. Today I check the oil and sure enough now I have more oil. Took the valve cover off and ran engine. Sure enough there is fuel sitting around no 2 and when shut it off and look back there is nothing there. What ever is there has gone back down the between the injector and the bore and I think I see air bubbles around no 3.. So I restarted the engine and sure enough there is air bubbles and fuel around no 3 and 4. The best I can see no 1, 5, and 6 are fine. I stuck a q tip at the bore of all of them and came back with oil on 1,5,6 and fuel around 2,3,4. since daylight short that is the only 3 I changed along with draining the oil. So the only o rings I have are off a set of rv 275s with 100k on them, nothing else available Sunday evening around here. They have also been sitting in a plastic bag for 3 or more years. I go to pull the injectors and they just lift right out, hardly had to apply any pressure. The o rings on the injectors are somewhat hard and when I took a pic to get them off the broke broke and hardly stretched. The ones on the rv s were stiff but still flexable enough to get off and back on the the other injector and  reinstalling the injectors required some force to get them to seat; So for now I think I am ok but hope the other 3 hold until the head comes in a month or so. I will be keeping a close on the oil level looking for some drop.

 Now for the double whammy. I go for a test drive and have a CEL lit. I have been getting an odd CEL with a 237 code for the past weeks, but the light would go out and everything ran fine. I have planned on going thru the engine harness while the head was off but now on the test I get another CEL and now have a 237 and 238. The scan gauge is not seeing the map and she is defueling as she was a few months ago. Not enough daylight for that one so I will have to do some checking next week.

 

The end of this job cant come soon enough for me, 

[Mopar1973Man]

Sounds like the o-rings need replacing for sure. I've got to ask how many miles on the injectors? It might be time to consider re-popping or replacing if close to 100k miles. 

 

MAP sensor codes. If the ground wire is open it could now produce the P0238 code because of no ground bias so the voltage would be high. The P0237 would be the +5V lead loose or becoming open circuit which would be low voltage. I've got to ask do you have the 2001 MAP sensor or the 2002 MAP sensor? If you have the 2001 MAP sensor you should have the adapter harness. 

[dripley]

1 hour ago, Mopar1973Man said:

Sounds like the o-rings need replacing for sure. I've got to ask how many miles on the injectors? It might be time to consider re-popping or replacing if close to 100k miles.

Over 80k but less than 100k. I know they are getting weak. Elevated idle until I drop below 5mph. Been have some hard start due to loosing prime. Mileage has been pretty normal though with Idleing and with short tripping does not help that. Also much shorter road trips to get a good comparison on highway mileage. That is my constant to keep track of mileage but not 150 miles from home.

 

1 hour ago, Mopar1973Man said:

 

MAP sensor codes. If the ground wire is open it could now produce the P0238 code because of no ground bias so the voltage would be high. The P0237 would be the +5V lead loose or becoming open circuit which would be low voltage. I've got to ask do you have the 2001 MAP sensor or the 2002 MAP sensor? If you have the 2001 MAP sensor you should have the adapter harness.

I have the 01 with the adapter. Has been like that for several years. If you remember I was having this issue a while back in Maryland. Pop a 237 and the SGII would pick up the MAP at 14.6 psi and run defueled until I would massage the wiring harness and it would go away. After finding the 5v splice at the ECM coming apart and soldering it together it stopped. Of course under the conditions I soldered it back together with a Bic lighter. Maybe I knocked it loose but was no where near the splice today.The weird thing was it was the 5v supply to all the other sensors that was cut. There is a separate 5v supply to the MAP and it was intact. They must tie together somewhere in the ECM maybe? maybe something is going on at the big connector on the fire wall. I was up against that alot today. Have to have a look around it at work next week.

[Marcus2000monster]

Everyone like aftermarket injectors but why don’t they last as long as oem? So many people put 150-250k on stock injectors without issues but aftermarket don’t last as long?

[dripley]

20 minutes ago, Marcus2000monster said:

Everyone like aftermarket injectors but why don’t they last as long as oem? So many people put 150-250k on stock injectors without issues but aftermarket don’t last as long?

in this case it appears to be the o rings. everything else seems ok. the o rings I used for replacement are 6 pr 7 years old with 100k on them and ben in a zip lock bag for the past 3. Big difference in quality on the o rings but until this the injectors have worked fine. Of course thats about as good as having a great clutch only to have the crappy throw out bearing fail prematurely, still have to pull the tranny for the fix.

 

[JAG1]

Interesting about the O rings Dripley.... I thank you for that information. I will be going for the OEM injectors next. New from Bosch they should be pretty reliable with the better O rings. I'm hoping anyway. I like reliability because my middle name used to be 'speed ticket'.

[Mopar1973Man]

1 minute ago, JAG1 said:

I like reliability because my middle name used to be 'speed ticket'.

 

That was me in Cally. Now being ticket free for nearly 25 years. I know when its safe to wind the old Cummins to a C note. Rare but I've done it a few times. 

[JAG1]

I could never could get it right..... always had the impulse to get on it right when there was a copper around the corner or hiding.

[pepsi71ocean]

23 minutes ago, JAG1 said:

Interesting about the O rings Dripley.... I thank you for that information. I will be going for the OEM injectors next. New from Bosch they should be pretty reliable with the better O rings. I'm hoping anyway. I like reliability because my middle name used to be 'speed ticket'.

 

Can I ask why your going to OEM injectors from larger injectors?

[JAG1]

Its all stock and is a work truck so it doesn't matter about power I want the reliability and seem to be hearing more and more bad on the aftermarket injectors. I could be wrong of course.

[pepsi71ocean]

8 minutes ago, JAG1 said:

Its all stock and is a work truck so it doesn't matter about power I want the reliability and seem to be hearing more and more bad on the aftermarket injectors. I could be wrong of course.

 

The issues with aftermarket injectors seem to be related around injector pop pressure. But that also seems to be something where most companies are also popping them lower. There's things that don't make sense about that.

[dripley]

The only reason I changed my oe ones out was because one or more started leaking fuel into the head. At 240k or so on them I never noticed any power loss or drop in mileage. Any power loss might not have been noticed since they were in so long though. 

 The fuel leaking was a good excuse to buy the RVs.

 

[Dieselfuture]

Sorry to hear about all your troubles dripley. 

You can buy new O-rings Cummins for few extra bucks, or I believe Gino's sells them. 

 

If anything I would at least get the RV275'S genuine Bosch for replacement @JAG1   

Edit 

If you're going to buy cummins had gasket set, it'll come with new orings and all

Edited January 28, 2019 by Dieselfuture

[dripley]

32 minutes ago, Dieselfuture said:

Sorry to hear about all your troubles dripley. 

You can buy new O-rings Cummins for few extra bucks, or I believe Gino's sells them. 

 

If anything I would at least get the RV275'S genuine Bosch for replacement @JAG1   

Edit 

If you're going to buy cummins had gasket set, it'll come with new orings and all

I am going to get my RVs rebuilt and give that a shot. Just hope the other 3 hold until I pull the head.

[dripley]

Old news here but I had to replace the other 3 the next weekend. The rest were shot too. 

 The 237 code came back and the I am running very defueled.  The most load I can put on the motor is about about 37% per my SG II. Finally got a short break in the rain and work today and did some testing for the 237 code. Engine running I had 4.98v on the 5v supply and 12.5v on the signal wire. Engine off and key on 4.98 on thr 5v supply and 18.5v on signal wire. Not sure what this is trying to tell me other tnan a wiring issue. Something shorted but voltages seem weird to my novice brain.

[Mopar1973Man]

10 minutes ago, dripley said:

Engine off and key on 4.98 on thr 5v supply and 18.5v on signal wire. Not sure what this is trying to tell me other tnan a wiring issue. Something shorted but voltages seem weird to my novice brain.

 

Very weird. The MAX voltage you should see is the current battery voltage. There is no system in the truck that amplifies voltage above the standard 12V system (~12 to 14.8 volts -running).

 

Need to ohm out from MAP plug to ECM plug. 

 

Quote

Manifold Air Pressure (MAP) sensor voltage is monitored when engine is running. DTC may be stored if Engine Control Module (ECM) senses low MAPsensor signal voltage.

 

Other DTCs

Boost Pressure Sensor - Is it damaged or failed? Try changing it out if you have a spare.

5-volt Supply Circuit - 5V circuit appears to be good according to your post above.

MAP Signal Circuit Short To Ground - Is the signal wire shorted to body ground?

MAP Signal Circuit Short To Sensor Ground - Is the signal wire shorted to signal ground wire?

MAP Sensor - Same as the Boost Pressure Sensor posted above.

Intermittent Wiring Problem - For sure a wiring problem being what you've documented in the past.

ECM - Highly doubt this at this point.

[dripley]

55 minutes ago, Mopar1973Man said:

Very weird. The MAX voltage you should see is the current battery voltage. There is no system in the truck that amplifies voltage above the standard 12V system (~12 to 14.8 volts -running).

 

Need to ohm out from MAP plug to ECM plug

I checked it 3 times key on engine running and key on engine off. 12.5v engine running with 14.1v at the battery and engine off key and read the 18.5v. Neither ade since.

1 hour ago, Mopar1973Man said:

 

Other DTCs

Boost Pressure Sensor - Is it damaged or failed? Try changing it out if you have a spare.

5-volt Supply Circuit - 5V circuit appears to be good according to your post above.

MAP Signal Circuit Short To Ground - Is the signal wire shorted to body ground?

MAP Signal Circuit Short To Sensor Ground - Is the signal wire shorted to signal ground wire?

MAP Sensor - Same as the Boost Pressure Sensor posted above.

Intermittent Wiring Problem - For sure a wiring problem being what you've documented in the past.

ECM - Highly doubt this at this point.

No other DTC's.

No spare to check with and with the cost of one I hope none is needed, we will see.

 

I cant help but believe that it is definitely in the wiring. But voltages on the signal wire were strange.

 

I put postive lead from volt meter on the sensor ground and got the same random numbers the meter gives when not connected. Not sure how to check the sensor ground for a short.

[Mopar1973Man]

13 minutes ago, dripley said:

Not sure how to check the sensor ground for a short.

 

Simple. Unhook both the ECM plug and MAP sensor plug. Then RED probe to the sensor wire of your choice. Then the black probe to the NEGATIVE battery post. It should show INFINITE ohms. Still, with it, all unhooked. The RED probe in the sensor pin. Then BLACK probe in the Sensor ground pin. This should show INFINITE ohms.

[dripley]

Now for another weather break and time.

[Haggar]

The signal should never be 12v......

 

The map sensor is supplied 5v (positive) relative to the sensor ground.  The map sensor is basically a rheostat (like the volume knob on an older radio)  It cannot have an output higher than 5v.  it is supposed to vary between 0vdc and 5vdc depending on pressure.   If you are seeing 12v  there is a definite problem. 

 

If 12v is really getting there, it is sourcing itself from another system. 

 

I attached the FSM page of the oil pressure and map sensor. 

 

Hag

2001 FSM Ram 8w-30-33.pdf