View Full Version : 97 Rodeo Knocking Noise

09-06-2006, 08:54 PM
I noticed lately after I got my timing belt,wp and tensioner replace I start hear knocking noise from the engine. It did made the noise before I got the timing belt changed but now its louder than ever. What might this be?

09-07-2006, 01:21 AM
Rod knock? Hopefully not.

A bad t-belt tensioner will sound alot like a rod knock so hopefully they replaced the whole thing and not just part of it.

09-07-2006, 07:44 PM
Whats the whole entire thing?

09-08-2006, 01:29 PM
I havent done a timing belt on these yet myself so dont know from experience but I beleive there is more then 1 part to the tensioner. I recall reading some posts on other sites about a knock still being there after changing the tensioner but they didnt change all of it.

Check the forums at ( and the rodeo section of ( and do searches for "timing belt tensioner knock" should have lots of info.

If you let your engine run really low on oil then it could very well be a rod knock. Usually the #1 cylinder since it gets the oil last so has the lowest pressure.

09-09-2006, 04:40 AM
Have much quart does a 97 V6 use?

09-09-2006, 05:00 AM
Also what should the oil gauage read?

09-10-2006, 02:07 AM
According to the Haynes manual it should use 5.7 quarts.

Mine doesnt have an oil pressure guage but this is from a post by someone that has a '99 trooper that he put an aftermarket mechanical guage in. I would think it should be around the same with a 97 rodeo 3.2

The mechanical gauge shows that although the <b style="color: rgb(255, 163, 79);">pressure[/b] goes up to 80psi+ when cold, as the engine warms up the <b style="color: rgb(255, 163, 79);">pressure[/b]
drops, typically showing 25-30psi at idle, 60psi at 1500rpm, 70psi at
2000rpm and peaking at 80psi at 2500 rpm up. The workshop handbook says
55-80psi at 3000rpm on a hot engine so my car is just fine.

09-10-2006, 04:12 AM
What type of oil do they recommend using? I use 10w-30

09-10-2006, 07:41 PM
I use 5w30 mobile 1 synthetic. Some are using 0w30 to help get rid of lifter ticking noises, others go as high as 20w50 to help with oil burning issues. So I dont think there is any set standard, just depends on what is wrong that you are correcting. I will say that 5w30 is probably the most common and what isuzu recommends.

09-14-2006, 01:13 AM
all rodeos do it :P

supposidly it could be the hydraulic lifters, but i just got it checked out and now they're saying it could be a worn-out pulley since it doesn't knock all the time.

09-16-2006, 03:39 AM
Now I got access to AllDATA and I look up some stuff about it. They said to change oil and use 0w-30 Molil 1 synthetic. They claim 0w-30 will allow air in the HLA to bleed out quickly and remove varnish that is preventing HLA pistontravel. Will using 0w be a problem?

Oh yeah they also said that the reason HLA tick is because of lack of oil change but the thing is I changed mine ever 3k miles with Castrol syntecblend.

Edited by: D16z6

09-16-2006, 05:37 PM
Using 0w30 should be ok. I dont know how much it helps. I know there are a couple guys on other boards who have used it.

My mitsubishi ticked for 15 yrs till I sold it. Sounded like a sewing machine. It had the same type of lash adjusters isuzu used. Changed oil every 3k, tried synthetic and flushes to try cleaning it, nothing worked. Eventually I just got used to it. All mitsubishis and isuzus with SOHC 3.2 engines tick.

09-16-2006, 09:15 PM
we used 0-30w at the dealership for awhile,back when the isuzu engineers were aware of the worked well with the vehicles that were just starting to tick,but for those too far worn it didnt do a thing.using 20-50 is the next thing we use with the higher milage engines,plus it helps with oil burn off

09-16-2006, 10:36 PM
So I better use it right now since it just started. I only have 76k miles.

Edited by: D16z6

09-16-2006, 10:42 PM
yeah try it out an see how it does for you,the correct fix cost about 1800 dollars to get them quiet again,some where in this forum i listed the procedure for the fix also,for someone who wanted to do the job

09-16-2006, 10:50 PM
it was a bad design by isuzu,just didnt deliver enough oil for the pressure that is up there,thats why they changed designs in really had to have used good quality oil an changed it early an on time everytime for them to stay quiet.which pepole seldom do.its not the lifters at worn was the shafts that they rode on that makes the noise an air getting trapped inside the lifters,thats why the 0-30w was recommended

09-18-2006, 02:15 AM
Is it true that a spun rod bearing will make a knocking sound due to lack of oil? For some reason im also thinking it might be this.

09-18-2006, 02:30 AM
Oh yeah why the heck did Isuzu make the oil dip stick black? You can't really see the oil level on it. Im probaly just gonna throw it out and get a aftermarket one.

09-18-2006, 05:47 PM
a bad rod bearing will make a heavy knock sound underneath the vehicle.the knocking sound that the timing belt tensioner makes is more of a rattling sound,if you think you have a bad rod bearing try killing the clyinders one by one an see if the tone will more than likely be number 1 or 2 clyinder is so.just hold the idle up til the sound comes in steady an rythmic,then pull a plug wire at the plugs not at the coil.....lowers the risk of getting listen to see if the tone changes or completly goes away.

09-18-2006, 11:40 PM
then pull a plug wire at the plugs not at the coil.....lowers the risk of getting listen to see if the tone changes or completly goes away.

Mine doesn't have a spark plug wire. Its distributorless.

09-19-2006, 04:51 PM
EVEN better just unplug each coil 1 at a time.

09-19-2006, 10:05 PM
Before I do anything is it possible to hear the rod bearing while driving?

09-20-2006, 02:41 PM
YEAH,thats usaully when its the most noticable.its proably the timing belt tensioner,rod bearings just dont go bad without some lack of oil changes,an oil deprived.i,m sure you have been changing your oil on time an keeping it full rightsmileys/smiley3.gifi would take off the right timing cover an peak down an look at the tensioner,if its wet in the center of it, then the oil in it has leaked out,and has collasped.causing the rattling can even watch it while it running an see it,s bouncing against the tensioner pully.

09-20-2006, 09:20 PM
Thats good then because I dont hear the noise when driving. I just replace my tensioner and timing belt recently too. So everything should still be good unless my mechanic did something to it.