Loud knocking / tapping noise

[95blueSHO3.2]

I have a knocking or tapping noise coming from the engine and I can't pinpoint it. It definitely sounds to be deep in the engine. It also appears there is an oil leak near what I think is the camshaft seal. I never did the 60K service for the valve lash adjustments and I'm afraid that might be it although I did read that 99% of the time they don't end up needing adjusted.

I have however changed the plugs(Bosch Platinum+4's - I read I shouldn't be using those), installed Taylor 8mm plug wires, and replaced the valve plug seals.

Also, the tapping appears to happen at idle but when I rev it, it goes away then comes back once I stop rev. With the window down I can hear it when I'm driving at lower speeds like in a parking lot and it happens all the time not just in the morning like the previous post. Please give me some ideas.

 

[95blueSHO3.2]

Oh yea, car has 118K.

 

[LOUDSHO92]

I owuld adjust your valves. It is true that some cars dont need it but it is a good preventive maintaince. It could be your chain tensioner has gone bad. I would check that.

 

[F-22 Raptor SHO]

A loud knocking on a 3.2 at idle that goes away when you rev it then it comes back when you come back to idle is symptoms of a bad timing belt tensioner. Does the knock come from the passenger rear side of the motor near the top? That is the number 1 cyclinder which would suffer if the timing is off. If in doubt, check it out....remove the upper timing belt cover and see how slack the belt is. SHould take 10 minutes to check....about 2 hours to fix (provided you have another tensioner).

 

[SeanMc]

My knocking is my fuel pressure regulator. Get a mechanics stethoscope, or use a screwdriver with one end on the engine, and the other end next to your ear. Have fun.

 

[95blueSHO3.2]

Thanks alot guys for the input. I have done alot of research myself and I too think it may be the timing belt tensioner. If anyone knows where I can get the best deal on one please let me know. I checked ebay already but no luck so now I'm going to look around the web. I looked on shotimes.com and I think they wanted like $160! That's alot more than I anticipated.

Anyway, I guess I should make sure that is the problem 1st.

Thanks again

 

[revhardSHO]

Post a WTB at here on the forum, someone could prolly hook you up with a used one pretty cheap.

 

[pete315]

did you check the plugs? I bought a 93 recently, had a slight tapping noise that I thought were the valves but sounded lower in the engine. while engine was running, I saw the front right plug wire moving. I pushed down on wire and tapping went away! I took off wire, plug was loose. I tightened plug up, put wire back on, started car up, and the noise was gone. engine now is super quiet. next week I'm changing plugs,wires,and valve cover gaskets. I have a feeling these are the original plugs/wires. will be doing belt also within the month I hope.

 

[95blueSHO3.2]

Okay, I have good news and bad news. The good news is I do believe the timing belt tensioner needs replaced because there was alot of slack on the belt toward the firewall closet to the tensioner but not on top.

The bad news is I went to start it just to watch how the timing belt looked to see if there was any play but the car won't start now. I think it may be the DIS module. I had to take it off to get to one of the upper timing belt cover bolts. I did over tighten one of the bolts causing a minor crack on the outer edge of the DIS but I don't feel it was enough to cause it not to start. The crack is on the bottom right edge of the bolt (maybe a mm in size that circles the bolt).

I think it may need some dielectrical silicone as stated in the Chilton's manual. I've gotten away without putting it on twice now (valve cover gaskets and spark plug wire change). Just how important is the silicone and would that make it not start?

 

[Rockledge]

The DIS module is grounded through the bottom screws. That's an important area.

If you are referring to the grease that goes on the back of the module, you don't want to use dielectric grease. You instead want to use "heat sink" grease which can be found in most electronics/computer stores.

 

[95blueSHO3.2]

Good News: After learning the screws on the DIS grounded it, I realized it wasn't completely grounded because I didn't have the 2 bolts in the top intake to form a complete ground. I left them out because I knew it would be coming back off to put the top timing cover back on. Also I softly hand wiped the back of the DIS with a dry cloth. Not sure if that helped or not but I'm quite sure it was the lack of a complete ground.

Anyway, it started right up and I was able to watch the timing belt and it does appear the timing belt tensioner needs replaced. I know a used one would be a **** of a lot cheaper but I'm thinking I might need a new one because the same thing could happen. Any suggestions or a place to get a cheap one please let me know.

Thanks - This forum rocks!

 

[quikSHOilver]

new tensioner suggested

Hey 95 bluey, I would suggest u obtain new tensioner since I got bad experience with used one...I bought one from a site( which I rather not to mention whom) turn out to be junk and wasted 3 weeks when u could had the part in 2 days for $125 FLAT. I got it from Payton Wells Ford in Anderson, Indiana. Try call around different Ford parts dept around Ohio. Hope that help u make more solid decision toward obtain new part. SHO on! Paul.

 

[allbuti]

Hope you don't mind my piggybacking, but I'm such a clutz I can't figure out how to post on my own. My 1992 (214k miles) has an occasional loud knock. The stored engine code is 225, which I believe indicates engine knock sensor. The car gets good gas mileage and does not use or leak oil, has plenty of power, but sometimes at light throttle it seems to hesitate. I've never heard the knock with the car in neutral, and there seems to be no correlation between the knock and bumps, turns or braking. What should I be looking for ? Thanks

 

[SHOtimer]

Just click the 'new' post button on the top of the section you want to post in. At that mileage, my first concern would be rod bearings. I would replace them - even if they arn't the source of the knocking to ensure that you will have that engine for a long time.

I would also investigate the timing belt - whether it is tensioned properly - maybe a new one is in order. Also, the cam chain tensioners can cause a knock.

If you are getting a knock sensor code, I would look into changing that. That is a lot of work - you have to pull the injectors.

But, if the knock is only when the engine has a load I would be heading straight for those rod bearings.

Doug

 

[allbuti]

Thanks. I think I'll try the rod bearings and the tensioner first. I have been good about changing the belts, so in theory I shouldn't need a new timing belt yet, but I may throw that in lagniappe. One thing puzzles me: if every once in a while there's a loud knock, isn't the knock sensor performing correctly by alerting me to the knock? If I can master the "new post" I'll keep you posted.

 

[Rockledge]

The purpose of the knock sensor is to tell the computer that the engine is knocking. When the computer gets such a signal, it retards the ignition timing until the kocking subsides.

When you get a valid code related to the knock sensor, that means that there is something wrong with the sensor itself (or the sensor circuit).