low oil pressure problem and knocking in left part of engine

[rangerdanger420]

just bought this a few days ago and it starts up fine but there doesnt seem to be much oil pressure reading, and after a little while of driving the knocking starts any ideas im pretty much lost when it comes to working on cars...

 

[Tedybear]

Ughhhhhhhh....not good...not good at all.

Basically the best thing to do is figure out what the oil pressure is really doing, and then a plan of action to deal with the results. The dash gauge is never been high on the list of dependable true readouts. So I would recommend the addition of an aftermarket oil pressure gauge.

Where does the knocking sound like it's coming from? Is it like a hollow knock, or sharp metal sounding knock?

At this time, I'd recommend doing a full oil change...maybe toss in a qt. of Lucas (4qts of probably 10w30 or 10w40 depending on how hot/cold your area is..and a qt of lucas)

Use a high quality oil filter. NOT FRAM! One of the better filters would be of course a factory one, motorcraft.. Mobile 1 makes a very good filter according to reviews...etc... (I personally like Napa's Gold line--made for Napa by Wix)

I'd check the oil in the drain pan for metal flacks or other debris. Sure sign of bearings getting ready to flake out.

Not sure what else to say? But depending on where/how bad that knock and the oil pressure is? That will dictate pretty much where to go from there. Keep in mind some lifter noise and hearing injectors "ticking" will be easy to hear---Just need to know if it's from the bottom end, or the top end.

S-

 

[harleytech]

mines been knocking at times for a year now ...i cant say that its good for it but doesnt seem to have hurt it the upper end oiling systems in these motors are really funky mine gets really bad when ur on the highway but once u get off and back into town it quets itself right back down usually

 

[engdept]

oil pump is your problem. Search the Tech library for the "2.9 knock"

 

[MAKG]

oil pump is your problem. Search the Tech library for the "2.9 knock"

Dammit, do NOT give advice if you don't know. This seems to be a habit here.

The oil pump is almost certainly NOT the problem. Pumps do not make pressure (they make volume, and pressure is determined by the resistance from the rest of the engine) and 2.9L pumps usually outlast the rest of the engine. Low pressure on a 2.9L is generally due to excessive bearing clearance, especially in the cam bearings.

 

[Hahnsb2]

Dammit, do NOT give advice if you don't know. This seems to be a habit here.

The oil pump is almost certainly NOT the problem. Pumps do not make pressure (they make volume, and pressure is determined by the resistance from the rest of the engine) and 2.9L pumps usually outlast the rest of the engine. Low pressure on a 2.9L is generally due to excessive bearing clearance, especially in the cam bearings.

The "knocking" you're hearing is likely a lifter tick.

 

[engdept]

I had always read that the lifter tick was caused by the oil pump; guess I read wrong.

 

[poweranger84]

mine has had a lifter tap since i got it... only does it everynow and then (sometimes loud and sometimes kinda quiet) but it hasnt effected the drivability,
but im gonna look at the lifters when i replace the valve cover gaskets sometime within the next few days

 

[Tedybear]

Sorry I've not been around recently. (internet was down for several days).

It might be helpful to use something like a mechanics stechascope (Yeah, I can't spell it LOL) I just use a harbor freight cheapo one, but it's actually one of the better test tools for location of oddball sounds. It should help locate a more direct source of the noise, lifter or otherwise. Lifter "tap" normally is a bit more higher pitched, but I've not worked much with these 2.9's. (used to work a lot with 302's and 351's)

Another trick would be, and this of course would only work at idle (if the knock is present at idle as well) Using a "tool" designed to remove plug wires--have the engine at idle, and remove a plug wire at a time. If you find one that makes the 'knock' change it's sound/pitch? That will help to point towards where to continue looking.

S-

(yeah...use extreme care when working with a hot, running engine)