zero oil pressure at stops

[SKAlexander]

I have read many of the threads related to this and believe that it is probably a faulty oil pressure sensor unit. But I can't find this item for 04 third gen at Geno's or any other place. Is it protected against repoduction and must be OEM from Dodge?

The problem is this. Oil pressure drops to zero at stop lights and lately going down an incline before I reach the stop light. This happens worse in winter; the past three have been near Denver so much colder than in Central Texas where I reside normally.

The problem is getting worse. Now it is every stop light and generally within a few seconds of stopping instead of a minute or two. And as I said on a decline as I brake. This is new. Although it did happen last year as I ascended a mountain. Seems to be much worse on a grade than level ground. It is mostly level back home but the problem is starting to happen more regulary there. However I had no problem in 100 degree plus days. I have been running Lucas but left it off. put in 15-40w and still same problem.

Suggestions?

 

[rbattelle]

When you say "... been running Lucas. " what do you mean? You've not been using 15w40 all this time?

Have you already verified that the engine is producing oil pressure using an independent gauge? That's the first step.

-Ryan

 

[SKAlexander]

nine quarts 15-40 with three quarts lucas. truch had 213k on it when I bought it and now was 292k. Engine never been opened. I haven't put an independent guage on it yet. not sure where to hook in seperately. can you advise me on a different port of entry for a mechanical guage?

 

[JBallou]

Tap in directly on top of the oilfilter housing.

 

[wcjp]

When my 12v did this the sensor was bad. Might have bought the replacement at Napa or O'Reilly.

 

[cerberusiam]

GET RID OF THE LUCAS NOW!!!! Then pray you have not seriously damaged the engine. NEVER run that crap in these engines or you will be sorry.



The reason you can't find and oil pressure sensor is because there is not one on a CR engine. It is a switch only in the normal place and the ECU decides what the gauge should say based on something nobody can verify. Do you ever get a CEL or warning light and chimes when it drops?



The gauage on the dash is set by the cluster controller based on what the ECU puts on the data bus. Multiple failure points there so take the readings with a grain of salt.



Get a manual gauge and tap it into the plug on top of the filter housing to validate oil pressure. You might want to consider immediately changing oil and runnin a couple quarts if MMO in the oil to try to wash the crap out the system the Lucas has generated.

 

[Nyoest]

Cerb why is the Lucas bad? I never run any of that kind of stuff, just curious.

 

[MChrist]

Cerb why is the Lucas bad? I never run any of that kind of stuff, just curious.

I can't speak to the effect Lucas has on motor oil, but in gear lube AND in trans fluid, it foams up. There is no oil in bubbles, so that may be your problem. I agree that you should dump that stuff out and go to normal oil. If light still comes on, add mechanical gauge. If you have a port on your oil filter housing, you can just stick a gauge there and have somebody rev the motor to check oil pressure. that way, you don't have to bother running hoses through the engine compartment, through the firewall, into the cab... delaying the project. It's a quick, dirty, yet effective answer to your question.

 

[AH64ID]

As it has been mentioned the stock sensor is a switch, a 6 psi switch to be exact. So either you are falling below 6 psi at a stop/down hill or the switch is bad. The ECM has to see < 6psi for 30 seconds to set a CEL, so you probably want to figure out what's bad. .

And run 100% oil!

 

[SKAlexander]

must be the sensor because there is never a clatter that indicates eng is not lubricating. however it does bother me that it mostly happens in colder weather at higher altitudes. I will check it with a manual this week. from what I have read on other forum threads, I thought the census was that Lucas was a good thing.

 

[SKAlexander]

and the control panel does flash and the chimes go on as the pressure starts to drop

 

[CKelley1]

go to autozone and get a copper line oilpressure gauge installation kit for $11it has all of the fittings needed and 6' of tubing get a cheap oil pressure gauge and remove the 1/8" plug from the top of the oil filter housing and install the tubing leaving the gauge loose by the shifter and drive it. this takes less than 5 minutes to install and you can see exactly what is going on. and as stated forget the lucas. stay with dello or rotella as it is available at wallmart and every truck stop. a quart of oil is only about 60% base stock and 40% additives from lubrizoil to get the best performance possible. the lucas dilutes a good oil

 

[AH64ID]

I've never read anything about people using Lucas in their crankcase for full time operation, or even short term.

You will probably have to go to Cummins or Dodge to get the part.

 

[cerberusiam]

Cerb why is the Lucas bad? I never run any of that kind of stuff, just curious.

In my experience it aereates too much and reduces lubricity. I have personally seen what it did to a diff and and an auto trans. The diff looked like it had metal run thru it on all th ebearings, the trans had sludge in it from the reaction of the additives to the treatment which toiasted the clutches. Based on that, I would NEVER run in a diesel engine with the amount of soot and stuff that is in the oil.

and the control panel does flash and the chimes go on as the pressure starts to drop

That means the cluster controller is working correctly and it is either the switch or the data bus.



Fill out your signature so we know what year of truck you have. It looks like you say you have an 04 but not sure if that was exactly what you meant.

 

[Prairie Dog]

GET RID OF THE LUCAS NOW!!!! Then pray you have not seriously damaged the engine. NEVER run that crap in these engines or you will be sorry.

The reason you can't find and oil pressure sensor is because there is not one on a CR engine. It is a switch only in the normal place and the ECU decides what the gauge should say based on something nobody can verify. Do you ever get a CEL or warning light and chimes when it drops?

The gauage on the dash is set by the cluster controller based on what the ECU puts on the data bus. Multiple failure points there so take the readings with a grain of salt.

Get a manual gauge and tap it into the plug on top of the filter housing to validate oil pressure. You might want to consider immediately changing oil and runnin a couple quarts if MMO in the oil to try to wash the crap out the system the Lucas has generated.

X2. Lucas is full of crap we don't need and it isnt oil. Ever notice it doesn't come in a specified viscosity? Your just watering your oil down. Hopefully your oil is just too thin to function well at idle (your pressure may be a few pounds in reality and not zero) and changing it will solve the problem. If not then it's rebuild time.