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Really LOUD Knocking/Timing???


tony4x4nc
06-22-2007, 08:09 AM
I have a 95 Rodeo 3.2 6. I have been reading a lot about the famous ticking.........I've used seafoam, ATF, Engine Flushes, 0W-30! I think the valve ticking is gone....now I have this really loud noise that sounds like its coming from the bottom of the engine when your laying under it aned sounds like its coming from the top when your over the engine. I recently changed the timing belt + Tensioner! I tore it down three times trying to make sure I had timing right (PITA) My timing is showing up as being about 3-4 inches past the timing marks on the timing cover......Is that to much? What should the timing be on these engines.....It's not in the chiltons manual. The engine also turns over about three times before it starts. The noise rises and falls with engine RPM and is always constant......no off and on. Could the timing being to far advanced cause knocking from my pistons? Can theses engines throw rods? Even worse what would a bad bearing sound like? Any help appreciated.........truck is embarisinglly loud!

Ramblin Fever
06-22-2007, 02:39 PM
What oil filter are you using?

Timing is automatically set at time of new timing belt. Wonder if you're off a tooth or two.

tony4x4nc
06-22-2007, 03:56 PM
Fram Tough Guard........How would a filter cause an engine knock like this? So i assume the timing is supposed to be on the little scale of 0-20 degrees? Mine is waaaayyyyy past that. Could the ignition sparking before the piston is at TDC cause piston slap that loud? I dont remeber if I checked to see if #1 was at TDC before I installed, but all the marks were lined up if its worth n e thing without #1 at TDC. The timing belt I bought didn't have two lines and a dotted one....it only had two solid lines. Im going to the Honda dealership in a few minutes to buy an OEM TB........I dont want to tear it apart again and adjust timing belt if the sound i'm hearing is a Main bearing. Waste of money! Has anyone EVER heard of having timing so advanced it sounded like rod knock?

Ramblin Fever
06-22-2007, 07:21 PM
I can tell you when my timing was off - jumped a tooth due to failing waterpump (which I HIGHLY recommend you replace while you're there as well) - it very well sounded like a rod knocking.

What had happened was the waterpump was freezing up, causing the timing belt to jump a tooth, weakening the timing belt tensioner - it's the tensioner that can make the engine sound like it's throwing a rod.

So, double check everything.

AND - BTW, get that Fram filter off as soon as possible, Fram's are the leading cause of ticking on these engines - not necessarily harmful, but a Fram does not filter the oil to the extent that these engines need to be filtered. And there are much better filters for around the same price - give or take $1 or so.

I use Napa Gold on my Rodeo with excellent filtering results.

But, that doesn't mean I've never used a Fram before - I was a heavy fram user for years, just never on the Rodeo, always made it tick.

tony4x4nc
06-26-2007, 07:44 AM
Purrs like a kitten!!!!! Changed the timing belt to the OEM........a lot easier to line up than the replacement I bought. Water pump and tension and pulley's were all changed previouslly. There is no more turning over twice tog et her started. Fires right up. There is still a slight ticking but nothing like the knocking that was thee. Going to switch the Fram filter this weekend. Napa Gold I've heard is pretty good. Thanks for your help.........was debating selling, "The Green Goblin" thought she had spun a bearing! Thanks again! Timijng still isn't where I think it should be but I have my power back and engine starts promptly. Whick cyclinder should I be checking timing on? Book says number 2 cylinder is at TDC when timing is correct. Do i check number 2 or number 1?

tony4x4nc
06-27-2007, 01:36 PM
Ok so today the noise came back.......I changed the oil and used 5-30 Mobil 1 with a Bosch oil filter. Also added some lucas oil additive. The noise is back. Not nearly as loud as it was. What does a spun bearing sound like and how can I tell if it's a spun bearing without tearing the oil pan off?

Ramblin Fever
06-27-2007, 07:31 PM
Personally, I hate to say this, but one of the worst things, IMHO, is to run engine flushes on higher mileage engines, loosens WAY too much stuff all at once - this could have caused bearing issues by clogging the oil gallies.

The bottom-end of these engines are built like iron, however, they generally only throw a rod if it's ran out of oil at some point.

The BEST combination for these engines, personally from my experience, is Valvoline Maxlife 10w-30 or Rotella synthetic 5w-40 with a Napa Gold filter.

Mobil 1 is famous for causing an engine to be louder then normal, according to a very informative oil forum/website bobistheoilguy.com - doesn't mean it harms it, however.

The ONLY two filters I can use on my engine; i.e. no ticking - Napa Gold and Isuzu OEM filter

tony4x4nc
06-28-2007, 07:59 AM
I've done three flushes in the past month changing the oil 3 times.....Do you think thats enough to get everything out? THe truck has 158,000. It sounds as if its coming from the bottom of the engine.......Just want to be sure. (Would be really ticked If I pulled the engine and it was someething else) Does a bearing change sounds at higher RPM's or is a constant. There seems to be no power loss. THe truck doesn't burn oil. I'm racking my brain trying to figure out what is going on. I'm considering selling it becasue the noise annoys me. I can only hear it with windows down and music off. I just want the thing to be quiet. What else can I do to eliminate the bearing?

surferfletch
06-28-2007, 01:55 PM
How old is the tensioner? I know you said it was changed previously.

Ramblin Fever
06-28-2007, 03:39 PM
Sorry, but I can't agree with you having a bearing issue. Typically bearing issues generally lead to using oil at a great rate of speed, and loss of power - of which you have neither.

Can I ask you if you are the original owner or is it a recent purchase? Reason I ask, is the Isuzu engine IS a noisey engine in general, however, if your's has gotten noisier, it could very well be due to the summer/heat, i.e. maybe it needs a slightly thicker oil.

This engine will NEVER be 100% quiet, they are not designed to be quiet; your typical Isuzu engine will sound somewhat like a sewing machine, some are much louder then others, but it will still be there.

If you have removed your timing belt tensioner - even if it is new - more then once while figuring out the timing belt, it'll probably need replaced again. Use OEM only parts.

Typically if an engine is clogged/sludged, you do NOT want all of it being cleaned out in short order - this is not good for the bearings.

I can tell you that when I changed my timing belt, tb tensioner, and waterpump, my truck quieted back down IMMENSLY! However, there's still a light tapping sound that will never go away, but it's much quieter then a much newer Pathfinder I was sitting beside the other day.

tony4x4nc
06-28-2007, 04:03 PM
I changed the tensioner about two weeks ago and have only pulled i once since I put it on. Still think i need a new one? I got it off ebay so i dont think its OEM. Thanks ramblin for the info. I purchased the truck in December with all the bad weather we got in Denver this year. Changed tranny fluid/filter, oil changes and flushes every 600 miles for the first month. the again just recetnly when I noticed the engine getting louder.

Ramblin Fever
06-28-2007, 07:23 PM
Ok, thinking of something else here since you mentioned living in Denver.

Where do you get your gas & what octane are you using?

tony4x4nc
06-28-2007, 10:20 PM
Get gas just at the local station down the road........mom and pop's gas mart.....I use 85 octane. Hell with these ridiculous gas prices and my college student budget I debated mixing half E-85 (2.19 Gallon) With half regular 3.08..........BUt quickly came to my senses and realized how stupid it was!!!!

Ramblin Fever
06-28-2007, 11:47 PM
I know you think it's ridiculous gas prices, I completely agree - I live in Colorado too.

But do NOT use just any mom-pop station, save those for last resorts only, you're not helping your truck any.

Visit and use Shell gas only, I run 87 octane, mine runs HORRIBLE on 85, I've tried it numerous times over the course of 10yrs. But my truck originally came from California, and spent it's first 5-6yrs in Vegas, NV that had 87 octane as the lowest rating.

You could also be hearing your fuel injectors, specially if they're the least bit clogged.

I continuously get incredible gas mileage on Shell gas, usually nothing less then 16mpg city driving in winter; and 19mpg city driving in spring/summer using nothing but Shell.

If I use Conoco or Diamond Shamrock even, it drops; Phillips 66 gives me good mileage too, but there's not one around here as a staple fill up.

I think our trucks could be converted to run on Ethanol, but I'm not positive.

tony4x4nc
06-29-2007, 07:38 AM
Thanks Ramblin.......I just ran a bottle of Lucas Injector cleaner through it. I think the noise is to loud to be injectors. Gonna try switching the gas....too bad I just filled up for 3.00/gallon at mom and pops yesterday. Could you or someone do me a favor and check your timing on #1. Is it possible to 180 a cam without the engine running really rough? Engine runs fine but my timing still seems off. I have power and everything My timing mark is just still past the little scale on the timing cover. I'm not positive I reset the ECM when I made the last change. Gonna try that today. Fifteen minutes minutes off the battery good?

Ramblin Fever
06-29-2007, 11:18 PM
I'd leave it off the battery for a good 1/2hr.

I apologize, I wasn't even the one that put on my new timing belt; have never done it myself on this engine. Wouldn't know any better then you, I'm sure, and I'll be honest, other then needing an oil change, this truck's running damn good, don't really want to dive into her - if you know what I mean.

Also, another thought, when was the last time you changed spark plugs, fuel filter, and have you ever cleaned your EGR valve?

tony4x4nc
07-05-2007, 11:10 AM
Yea I know what you mean. Changed fuel filter bout 3 weeks ago, spark plugs 4 months ago when i first got the truck. Never done EGR, would it cause engine noise?

Ramblin Fever
07-05-2007, 12:07 PM
It could attribute to *some* engine noise, but not to the extent of the sound of a rod-knocking.

Remember, Isuzu engines are noisey in general, if it's truly a rod-knocking you should be able to hear it inside your house with the door closed.

Otherwise, I think you may be at a dead-end for resolving the noise, aside from trying Valvoline 10w-30 oil, it really DOES seem to quiet this engine.

rodeodrive
07-05-2007, 03:59 PM
Does anyone use 89 octane or higher? When I first got my 95 rodeo two years ago, gas prices weren't so high and I didn't have my 100 mile/day commute. I noticed when i used 87 it knocked and not so much on 89 or occassionaly 93. I have been using 87 reguraly now becuse of the cost and the amount I drive. I just changed my oil and used the recommended Napa gold filter and 10w30, it's better but still noisy. I'm at 1/4 tank, I think I'm going to change my fuel filter and fill her up with 89 and see if it makes a difference.

Ramblin Fever
07-05-2007, 06:59 PM
Mine runs good on 87 octane; HOWEVER, she's a pinger at low altitude - anything below 6k feet - regardless of fuel used. Never knew why - gave up trying to figure it out, I live at 9k feet, she's quiet up here.

When was the last time you took that baby for a DRIVE? I mean a serious, good 2-3hr highway drive? Maybe she could use a good heat-em-up to get the cob webs out, I know mine starts to run *different* if it doesn't see a good highway stretch at least once a month.

tony4x4nc
07-06-2007, 11:03 AM
New plugs 3 months ago, new fuel filter 2 weeks ago. Have not cleaned the EGR (this weekends project) Can anyone out there with a timing light check to see what it is on #1? Also, the truck seems t be taking a little longer to get up to speed....could this be the tranny going? Would another fluid/filter change help? I changed it in March wehn I first got the vehicle....I don't know the history past March.

Ramblin Fever
07-06-2007, 09:09 PM
I think the next step is to do a compression check.

Let me see if I can dig into my haynes manual and see what the timing is supposed to be set for.

trooperbc
07-06-2007, 10:46 PM
.....

tony, there is so much talk about this and talk about that, i really can't figure what you want to resolve anymore.

do a favor. take a breath. re capsulize what is going on, its history, its impact. maybe do a list with numbers -- 1. 2. 3. etc so a step by step diagnosis from afar can have half a chance...

thanks

//bc

tony4x4nc
07-09-2007, 07:44 AM
1. Had a loud ticing noise (LOUD)- Changed Belt and tensioner with ebay TB, Timing was off so I bought a belt form the dealewrship and it had an extra alignment mark on the belt. Everythings goog there. The noise subsided not quite as loud but still louder than I wanna hear. I've been told these engines are loud.

2. Truck ran fine for a few days and seems kinda sluggish now. Slow to get up to speed. I cleaned the EGR this weekend- no diference. My question is could this be the tranny going, and would a fluid/filter change prolong it any? Or is my timing off? All the manuals I've checked said nothing about what the timing was supposed to be because it's done electronically. With the timing light on #1 my timing is about 1 to 1.5 inches past the last mark on my timing cover. As the engine revs, it advances like it should it just doesnt feel right to me.

tony4x4nc
07-09-2007, 07:48 AM
Next step compression check.........does anyone know what compression should be?

Ramblin Fever
07-09-2007, 10:59 AM
Tony,

When was your last ATF/tranny service?

Is this a vehicle you've owned for a time, or just recently purchased?

tony4x4nc
07-09-2007, 11:14 AM
I did a partial in Feb or Mar......no filter change though. I just made a new thread about it.

trooperbc
07-10-2007, 01:14 PM
...

2. Truck ran fine for a few days and seems kinda sluggish now. Slow to get up to speed. I cleaned the EGR this weekend- no diference. My question is could this be the tranny going, and would a fluid/filter change prolong it any?

Or is my timing off? All the manuals I've checked said nothing about what the timing was supposed to be because it's done electronically. With the timing light on #1 my timing is about 1 to 1.5 inches past the last mark on my timing cover. As the engine revs, it advances like it should it just doesnt feel right to me.

tony --
2a. from what you have written, i don't think it is a tranny thing. a slipping transmission should be quite obvious, different from just a sluggish lack of power. but...test it. if it were a manual, you would put it third at the bottom of an incline and pour on the gas, and that would tell you right away if your (manual) clutch were slipping. with the automatic try something similar on a hill, just jamb on the gas.

2b. is the timing off? maybe. i just checked my 1992 3.2. v6 with a timing light for you, which should be the same as yours. it reads 10* BTDC at 750 rpm in neutral and about the same in drive.
yes, the timing is computer controlled, and the computer takes many different things into consideration. the 'base' timing spec is 5* BTDC. this base is then adjusted by the computer with a number of inputs [[ i'll look up the list and post it later ]]

i thought there was a way to check the base timing by disconnecting something, but i can't find that info, and i don't remember exactly, and i may be disremembering anyway. there is a way to check it using the extrafancyexpensive Tech1 Scan Tool which has the capability to actually change sensor etc values to the computer.

fyi, the timing scale on my 92 trooper shows only 20* 10* 0* (btdc). which direction is your timing off the scale?

what's the rpm when you check your timing with the timing light? try it in and out of gear (careful...) to see if there is any change in the timing (which might be a clue).

so, it does sound like your timing is wrong, and the first suspect would have to be whether you got that timing belt installed correctly with *all* the marks aligned correctly; but only you can determine that.

since the truck ran fine for a few days, one wonders if the belt skipped a tooth or two. did you use a dealer tb tensioner, and are you confident that you installed that correctly?

maybe the list of inputs that affect timing might help.

//bc

tony4x4nc
07-11-2007, 07:53 AM
Wow.....thanks for all that helpful info trrop! If your facing the engine my timing is to the left of the mark (advanced). The one thing I meant to do earlier that Ramblin suggested was to disconnect the battery for about half hour to reset the ECM to see if that does the trick. It kind of makes sense now. The Tensioner I got was not factory. I got it off ebay. Could the timing be so advanced that i'm hearing a "Piston Slap" sort of sound becuase the fuel is being ignited way before TDC. Wouldn't that make the truck feel sluggish since the engine is working against itself? I'm gonna unplug the battery on my break and let it stay off until I get off and will repost tonight.

trooperbc
07-11-2007, 12:48 PM
it could very well feel sluggish because if the timing is advanced to start with it reaches its limit on the advance curve prematurely. from here just from reading i'm thinking it is the timing set up wrong, but no way to know that. i'm of the mind that the noise and the other stuff are not related, although if the tb tensioner were inferior or installed incorrectly, maybe they are in that sense.

resetting the computer by disconnecting the battery will do a couple of things (and only 30 seconds will do it). it will clear the codes so you can know that any you get from now on are current. it will also clear any driveability memory and it will relearn and store certain data and settings, which will take a number of drive cycles to do.

what manual are you using. consider the factory manual from
www.helminc.com (http://www.helminc.com)
or a pdf version available 'out there'.

//bc

Ramblin Fever
07-11-2007, 06:25 PM
If the tb tensioner is bad, it WILL make the knocking noise - this is very common on Isuzu's.

tony4x4nc
07-12-2007, 07:51 AM
I'm now questioning the tb tenssioner being bad. Seems to me if the tensioner was bad as RPM's went up the tb would trun faster and the noise would speed up. As the tranny upshifted Rpm's would decrease causing the noise to go down. My noise increases and stays constant.

trooperbc
07-12-2007, 01:24 PM
I'm now questioning the tb tenssioner being bad. Seems to me if the tensioner was bad as RPM's went up the tb would trun faster and the noise would speed up. As the tranny upshifted Rpm's would decrease causing the noise to go down. My noise increases and stays constant.

it's hard to tell at this distance, of course,


typically the tb tensioner will going will create a *very* loud knock as a thrown rod, but the noise will disappear at ~2000-2500 rpm.

//bc

Ramblin Fever
07-12-2007, 06:53 PM
When my tensioner went bad, my noise did NOT disappear, course, it was so loud that I was leary of even taking it out of the driveway. It got towed on a flatbed to the mechanic.

trooperbc
07-12-2007, 10:26 PM
When my tensioner went bad, my noise did NOT disappear, course, it was so loud that I was leary of even taking it out of the driveway. It got towed on a flatbed to the mechanic. so did you have it reved in the 2500 rpm range?

//bc

Ramblin Fever
07-12-2007, 11:25 PM
Yes. The sound was still there, in fact it was LOUDER!!

FWIW - at that timing, my timing belt DID skip a tooth, the waterpump seized and the tensioner gave in all at the same time. For all I know, it could have been the combination of noises.

But, soon as all was fixed, quiet as a mouse.

tony4x4nc
07-13-2007, 07:38 AM
I'm gonna take a video clip of the noise and will create a link for it tonight......have a softball tourney tomorrow so it might be tomorrow night before it's posted.

Ramblin Fever
07-13-2007, 11:39 AM
Tony - when you do that clip, clip it from the passanger wheel-well. That was where my noise was the loudest.

tony4x4nc
07-13-2007, 03:23 PM
Hey troop what cylinder did you check your timing on? I assuming #1? One of the manuals I have says that #2 will be at TDC when the timing marks are aligned. Does that mean timing should be checked on #2?

jskadberg@mac.com
02-17-2008, 10:24 AM
This week at the end of a 1700 mile trip I noticed a clatter/ knocking noise that sounds like a A/C compressor, but makes sound when A/C off. Noise is constant under load or no load and increases linear with engine speed. Did not notice it on the road. Engine does not miss, no loss of power and no blow by when you remove oil cap. My Rodeo V-6 has 144,000 miles, uses no oil and I don't know when or if timing belt has ever been changed. It does get the ticking noise at 3,000 miles on a oil change and goes away after change. If this is timing belt tensioner will driving it risk catastrophic failure? I had it towed to town and had scheduled mechanic to come listen to it, but he has not made it out yet.

If this is timing belt tensioner do I need to buy the parts from Izusu? I'm assuming it will be belt, tensioner and water pump replacement. I did not see anything on Ebay.

BTW I have Mazda Protoge that has serious ticking noise at 140,000 miles (sticky lifter) and switching to synthetic oil after Marvel Mystery oil treatment made a great improvement.

FL 3.2L
02-17-2008, 06:19 PM
I would highly recommend Isuzu parts. Having said that, though, I used Advance for all of the parts except the tensioner, which I got through St. Charles Automotive in MO. Call their 800 # and ask for Merlin. You will find kits on eBay and in the big box stores...

FL 3.2L
02-18-2008, 08:19 PM
To the top for more comments...

trique
02-24-2008, 07:43 PM
I am having a similar problem right now with a 1997 3.2L. It sounds violently loud with consistent rhythm, but still runs and does not feel like a valve problem so I don't think it threw a rod. At about 3,000 rpm it isn't as bad but it sounds like a loose tool or bolt in there beating around, but not nearly as violent.

About to replace the tensioner tomorrow morning. A buddy of mine told me that the tensioner will have a lot of play in it if it is indeed what is bad. I will update later with the details of my venture.

Ramblin Fever
02-25-2008, 01:44 AM
If you're going to take the time to replace the timing belt tensioner, might as well replace the timing belt and waterpump at the same time; this is not something you're gonna want to do again in short time.

Also, if your timing belt is original, being 11yrs old, it's definitely time to change it and the waterpump.

HeadlessHorseman1
02-28-2008, 07:37 AM
If you're going to take the time to replace the timing belt tensioner, might as well replace the timing belt and waterpump at the same time; this is not something you're gonna want to do again in short time.

Also, if your timing belt is original, being 11yrs old, it's definitely time to change it and the waterpump.
I just finished replacing the timing belt and water pump on my daughter's '97 Rodeo with 99K. It didn't occur to me to replace the tb tensioner. Does anyone know what the expected life of the tb tensioner is?

Ramblin Fever
02-28-2008, 09:00 AM
Generally the TB Tensioner fails before the TB. If you put a new belt on without a TB Tensioner, they generally follow suit in failing quickly.

GoodGord
02-23-2010, 02:17 PM
94 trooper timing cover noise clatter solution:
I had this noise coming from the timing cover that sounded like knocking at low RPM. It would diminish over 2,000 RPM. I've seen where people have been told its their rocker assembly or some other expensive fix, but the solution is the hydraulic timing belt tensioner. Not that it's cheap, but it is the solution.
5 hours labor, per the book. The tensioner is over $600 from Isuzu/GM, and under $200 from a Jobber. I replaced the other timing cover tensioners at the same time (note that the GM tensioner kit does NOT include the one hydraulic tensioner...!). Changed the belt at the same time and I should be good for the next 100,000 km. With 5 hours labor, you might as well...
Anyways, purrs like a kitten again, and roars like a tiger when I floor it. I forgot just how quiet the 3.2l 24V DOHC is when the hydraulic tensioner is working right. That clatter noise builds up slowly over time. This fix likely works for any engine that uses a hydraulic tensioner.

steve1968
03-09-2010, 08:34 PM
Fellas, just found this fourm, I'm helping a friend with a 95 Passport,

it had the dreaded tick, so he changed the oil add some Z max, and a couple of other lubes, but the ticking is back and louder than ever, it actually sounds like 2 pieces of metal banging together,

I was thinking rocker/hyd adjuster, in the valve train, today I took the V/C off but nothing is broken or collapsed, I guess I need to look at the book, any ideas in the hyd tensioner?? it would be easyier to hear but the friggin starter is so loud, so, right now I'm looking for ideas, thansk Steve

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