Engine knock or tick, help diagnose

BCanuck · Mar 25, 2015

I just bought a 94 Ranger 3.2L manual. After lots of searching on here, google, and probing with a screw driver, I can't seem to track down the noise.

The tick or knock only happens when the engine fully warms up and is intermittent. If I speed the engine up, the noise goes away. I don't think its bottom bearings as the sound goes quiet with higher rmp's.

No check engine light.

https://youtu.be/z8HHct2R6U0

RonD · Mar 26, 2015

2.3l is an OHC(over head cam), from description I would say valve train for sure.
So worth while pulling the valve cover off.

Oil of course is thicker when cold and thins out when warm.
Oil pressure gets higher as RPMs increase.
Oil pressure is also higher when oil is cold.

"tick or knock only happens when the engine fully warms up and is intermittent"
When oil thins out and pressure drops

"If I speed the engine up, the noise goes away"
Higher oil pressure with higher RPM

Because it is intermittent it would be better to find out what it is now, because it will just get worse over time.

Could it be the oil pump, sure, just not as likely as a worn valve train part.

BCanuck · Mar 26, 2015

Thanks for the reply.

I hope its top end as I can repair that. I picked the truck up off a friend for $200 and is a project so it will be parked.

Is there any diy info on repairing these engines? (Top end)? I don't have a factory service manual but I'm ready to dive right in. I just finished doing valve seals on 3 of my friends vehicals.

The oil guage shows good oil pressure (not sure how accurate the cluster guage is)

Mark_88 · Mar 26, 2015

Not sure if there is anything on a 94 that can be seen under the valve cover to be honest. I pulled my valve cover off on an 87 head and there was nothing there to see (have a rather loud valve clatter a few times)...I thought maybe I could adjust something...and maybe I could have if I knew what I was looking for...but I could not see anything that I could get a socket or wrench on so I ruined a perfectly good valve cover seal (those blue rubber gaskets that are like $50 a pop)...I eventually got it sealed again though...

I would say it's probably not going to be something you can see either way...and I may be wrong...as per usual...lol

With the noise getting louder with higher rpms it could be a spark noise or bad wire noise...so make sure your radio is completely off (spark noise can be heard through speakers if not properly shielded)...other than that...check that the oil level is fully topped up...even with good oil pressure reading...depending on oil pressure gauge...didn't see the back end of the engine to see if there was a proper (real) oil pressure gauge...

BCanuck · Mar 26, 2015

Hi Mark.
To me the sound seems too loud to be a spark issue. It idles and runs without a miss fire.

When the rpm's raise, the sound goes away.

I can hear it mostly in the front of the engine. I don't hear much noise with the screw driver on the valve cover.

RonD · Mar 26, 2015

There won't be any valve adjustments, the system is suppose to adjust automatically, which is great 99% of the time, but a part can start to wear and fail for that always occurring 1% of the time.

I would remove one spark plug from each cylinder, so you can rotate crank manually, then with valve cover off see if you can fine a loose "rocker", rotate crank a few times to check each valve's "rocker".
'94 should have roller rockers, I think, rollers can go bad.

hopster · Mar 26, 2015

the oil presure gauge in the cluster is NOT accurate. hook up a manual oil pessure gauge and check it.

BCanuck · Mar 26, 2015

I was planning on picking up a oil gauge. Is there a test port on the back of the engine or near the oil filter?

I haven't worked roller rocker as of yet but have read a lot about them.

BCanuck · May 29, 2015

Time to bring my thread back from the dead... I sold my VW and now I'm ready to tare into this project... I should start a "Save a ranger project rebuild thread"

So i got an oil gauge. Where can I connect it on this engine? Do I have to pull the oil sending unit out?

Also aside from the various oil leaks, i found a broken vacuum line which came off the smog canister.

RonD · May 29, 2015

There are 3 kinds of oil gauges
1. The kind you have in the Ranger now which works with an ON/OFF pressure switch/sender
2. an electric pressure gauge that works with a PS60 variable resistance oil pressure sender, yes you would need to remove existing sender and put PS60 in it's place and run a new wire to new gauge inside cab.
3. an actual oil pressure gauge that requires an oil tube from the engine to the gauge, yes you would remove existing sender and put the oil tube in it's place.

Usually swapping out sender will require some 'plumbing' parts to get the correct fits, not really a plug 'n play item.

No "smog canister", there is an EVAP system charcoal filter and a vacuum reservoir.
Broken vacuum line is never a good thing.

BCanuck · May 30, 2015

Sorry i should have stated that that the gauge I got is not electrical. I was hoping that there was a unused plugged port like my 350 Chevy had so I could tap in.

The vacuum leak is probably why my friend and PO had a rough idle and poor gas milage.

RonD · May 30, 2015

Many use a "T" fitting to run both from the one port.

rangerin · May 30, 2015

RonD said:
Many use a "T" fitting to run both from the one port.

I've done that in my Ranger. That way I have a light and a gauge.

BCanuck · May 30, 2015

I just ran my mechanical oil pressure gauge and I got...
60 psi cold
52 psi warm

The truck has been sitting for a couple of months and I noticed the sound is starting right away cold and still there when warm. The sound speeds up but as the rpm goes up enough, the sound goes away.

Next test is to run it while pulling a plug off each cylinder...

BCanuck · May 30, 2015

Pulling one plug at a time did not change the sound...

Engine knock or tick, help diagnose

Member

Official TRS AI

Member

Well-Known Member

Member

Official TRS AI

Member

Member

Member

Official TRS AI

Member

Official TRS AI

New Member

Member

Member

Sponsored Ad

Sponsored Ad

Member & Vendor Upgrades

Truck of The Month

Recently Featured

Follow TRS On Instagram

TRS Events

25th Anniversary Sponsors

Check Out The TRS Store

Sponsored Ad

Sponsored Ad

Sponsored Ad

Amazon Deals