Really LOUD Knocking/Timing???

[Ramblin Fever]

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]

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]

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]

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]

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]

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]

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]

Originally Posted by tony4x4nc

.....

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]

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]

Next step compression check.........does anyone know what compression should be?

[Ramblin Fever]

Tony,

When was your last ATF/tranny service?

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

[tony4x4nc]

I did a partial in Feb or Mar......no filter change though. I just made a new thread about it.

[trooperbc]

Originally Posted by tony4x4nc

...

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]

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]

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
or a pdf version available 'out there'.

//bc