Constant Loud Engine Clicking

[jimprusa]

I own a 1996 4.0 4x4 XLT with about 79,000 miles. The engine developed a constant loud clicking -- much like a loud lifter clicking. I have
been desperately trying to troubleshoot in order to isolate the problem.

Noise stays the same whether cold or hot. No change whether at idle or with engine under load (I lock brakes in drive and rev engine -- no
significant change in sound).

I have disconnected each spark plug wire one at a time with no change in the clicking noise level on any disconnected cylinder firing.

Removed opposite plug wires on front and back of V6 with no change in clicking noise level.

Finally I removed the accessory drive belt to idle the water pump, alternator, air, and power steering for a brief test. No change in
sound.

Oil changed also -- nothing.

Any suggestions. I no longer think it is a rod or main bearing after all this checking. Any suggestions for further checking now? Please
help as I'm stumped.

Jim
mailto:jgp@alumni-gsb.stanford.edu

 

[adamsbro1]

I have a 91 X that developed a pinging kinda like that i did everything i could when i finally figured out that it was pre detonation, the fuel firing before the spark. i got my gas tank down as low as i dare before runnign out of gass then refill with Premium gas. and continue to run premium gas. and it fixed my prob. However everytime i get regular it comes back so you have to stick with premium. Might wanna try it once see if it helps.

 

[Sherwood]

engine noise

You might want to look into the cam chain tensionorl. There was a "m" code recall on them. It is only for the 4.0's I believe. I just had mine done on my '98 Sport. It made a loud ticking noise like a lifter knock. They replaced the tensionor and o rings. Didnt cost me a penny. But with 79,000 miles on your motor. It looks like you may have to pocket the expenses. The recall only goes for so many years and miles and if im not mistaken, it only covers up to 70,000 miles. You might want to call Ford on this or your local dealer and get the specifics. Hope this helps. Eric

 

[bandlow]

1995 XLT 4D 4WD 107,000

I don't have any info for you now but mine started doing something similar today. It's a metallic clicking proportional to engine rpm, clearly audible at idle.

I'll start troubleshooting tomorrow. I'm hoping it's a water pump but that may be wishful thinking....

I'll keep you posted. Let me know if you find anything out.

Rich

 

[bandlow]

Jim,

I bought a $9.99 stethoscope from AutoZone. Even though I haven't pinpointed the problem it was fun listening!

I eliminated the the external rotating components (AC compressor, alternator, PS pump) and the water pump. The clicking is audible through both valve covers. It seems to be louder around the #3 cylinder but I'm not sure of that yet.

I assume that since you have a '96 you have a SOHC where I have the OHV. If our clicking is similar/the same that might point to timing chain or tensioner. (Looking at Chilton's the SOHC has four chains!)

My plan is to remove the valve covers to look for obvious problems since that's easier than dealing with the timing chain at this point.

If you have made any progress, please let me know.

Thanks,

Rich

PS: If I can figure out how to do it, I'll send you a .wav file of the sound to see if it's the same.

 

[hskrbkr]

Mine does something very similar so I did a search for 'engine clicking' on this site. After reading multiple threads on this topic, I came to the conclusion that the noise is being caused by the fuel injectors. Other than annoying, it doesn't seem to be a big deal.

You might try searching for threads that deal with 'engine clicking', 'fuel injector clicking' or something like that.

 

[COMMOCOZY]

My Chevy used to do this also. I have the same problem.


I think if you get under the truck on the pass side you will hear it clearly. This called Pistion Slap ( i believe) it is basicly just play between the piston and the wall of the block.

Chevy told me this will not hurt anything, but if you hear anything different please let me know.

 

[yob_yeknom]

Use the stethoscope and put it up against the timing chain cover. See if you hear anything in there.
I had a Dakota with the same problem. It turned out to be the timing chain. It had worn out and had too much play in it. Put in a new timing chain and no more ticking.

 

[flatlander]

I took my 97 sport in about 6 months ago and it was the timming chain that was bad. Since they replaced it I haven't heard anymore ticking. Another thing to check is the headers/exhaust manifold if the bolts get lose they will make a sound just like lifters will.

 

[bandlow]

Progress Report

Jim,

I don't know if you have made any progress or had the clicking in your engine fixed. Just thought I'd update you on what I'm doing.

I have removed the passenger side valve cover. Everything appears clean and in order. Pushrods, rocker arms and springs move correctly when the engine is cranked. No evidence of lack of lubrication.

I did find one thing that you might want to check although the differences in our engines might make it unimportant. (You do have the SOHC don't you?)

When I removed the upper intake manifold, I noted that the stud bolts on either side of the #3 cylinder were corroded. I didn't think much about it until I decided to remove the fuel rail so I could remove and clean the lower intake manifold.

The stud bolts on the OHV engine have two functions: they are a threaded shaft for the upper manifold retaining nuts and are also retaining bolts for the fuel rail. The stud bolt furthest back was less than finger tight and had backed out about 1/4 inch.

I'm curious if the bolts had finally backed out enough to allow the fuel rail or upper manifold to "jump" and cause the click as the intake air was forced out the side. Its a long shot but the only abnormal thing I've seen so far. (Except that there was no gasket between the upper intake manifold and the fuel rail even though the manual mentions one.)

The SOHC has a different manifold/fuel rail set up but you may want to check the manifold and fuel rail hardware.

I'm going to remove the other valve cover and the lower intake manifold. (I'm undecided yet on removing the heads to check the lifters. I guess I should while I'm this far along.) Then I'll clean everything up and reassemble it with new gaskets.

Regards,

Rich

 

[Robert]

Rich - Jim has the same OHV that you have. The SOHC didn't come out until model year 1997. Since Jim's is a '96 it looks like he has something else to look into.

 

[bandlow]

Robert,

Thank you. I was under the mistaken impression that I had the last year of the OHV. Checking the chart in Chilton's I see that the SOHC didn't become available until 1997 and both engines were still made that year.

I appreciate your bringing that up since if Jim has loose stud bolts also that might be the cause of the clicking.

As I mentioned, there was no gasket between the upper intake manifold and the fuel manifold. The Ford Manual shows one in the diagram and the photos in Chilton's clearly show one in the disassembly.

The replacement gasket set I got has two gaskets for the fuel manifold: presumably one for above and one for below. I was curious when I removed the upper manifold that they would design plastic to metal contact with no gasket.

Now I wonder if the gasket was not installed at the factory (either inadvertantly or as a design change) or was left out during the red hot dealer service that I subjected my vehicle to during its first five years. (The same dealer service that prompted me to start maintaining my vehicles myself.)

Does anyone out there know if the fuel rail should have one or two gaskets? I'm going to put in two when I reassemble it.

Thanks again Robert,


Rich

 

[bandlow]

Progress?

Today I put both valve covers on, reinstalled the lower intake manifold, fuel injectors and fuel manifold. I installed a gasket under the upper intake manifold.

Other than the loose upper manifold stud bolts I didn't find anything wrong.

After reconnecting everything, I tried a start. To my surprise, it started right up. The clicking was still there along with a flashing O/D OFF and CHECK ENGINE light.

Considering everything that I had disconnected I figured that I had an unconnected plug. I had stuffed the connector to the Throttle Position Sensor out of the way and also out of sight. I fished it out and plugged it in.

I started the engine again and the lights were gone but so was the clicking!

I've only driven it enough to reset the computer so I'm not sure that it's gone for good. The only thing to do is to drive it a few days and see what happens.

Do I know what caused the clicking? No.

Do I know what stopped it? No.

Did I take too much apart? Probably. But I had a good time and judging by the gunk on the injectors (the nozzles were clear) and in the intake manifold I should probably move up my schedule for a rebuild.


Rich

 

[COMMOCOZY]

Do a search on PISTION SLAP. This is your problem. I just saw a post the other day saying someone had the motor replaced for this.

Like i said in another post had the same problem in a chevy and they CLAIM it will cause no problems other then being annoying!

 

[Jenkins1581]

MIGHT BE SOME HELP!

I have a 96 XLT. At about 90,000 it did the same thing. It turns out that the rocker arm to push rod pockets are made of a weak metal. After some miles they wear out and start to knock. Most peaple think it is the lifters. Sounds like the liffters. Its not! Go to deltacam.com. They have a replacement that is in expesive. Give them a call they can help. It worked for me. It ran about 200.00 for the rocker arms and new push rods + shipping.



Richard Jenkins