2001 Honda Passport Rattles when accelerating

I have a 2001 Honda Passport (similar to the Isuzu Rodeo). When I accelerate, I hear a rattling sound. I’ve taken it to three different mechanics, each of whom have diagnosed the problem as something different, ranging from $400-$4000 solutions. One even warned me that my car would “explode” on the highway somewhere, and drop out all of its innards.

Has anyone experienced this problem before? Any guidance on how to decipher what the problem is?

Rattling sound.

That could be anything. Really, you’re going to have to do some research on your own with the vehicle and try to get somewhere in the vicinity of the noise. Motor? Rear end? Front end? Underneath?

It could very well be nothing more than a loose clamp somewhere on your exhaust system (which is really a likely culprit), and it could be something more serious.

It sounds like the front end, underneath. The noise is a rattling noise that increases on acceleration, but is blocked out by the sound of going over 50 mph.

Many things can rattle however at that age…I would seriously suspect a loose heat shield in your exhaust system… There are actually quite a few on your vehicle…and it is VERY common to have them get loose (the spot welds rust) and they make quite a racket… Not too hard to decipher whether this is the case however…

A tip for you… Have an assistant get in the van…Have them put it in gear AND their foot on the brake then with foot on brake…add some gas…like you are trying to accelerate…but hold the vehicle back with the brakes…this will usually incite the offending heat shield to rattle…IF its a shield… The shields when they rattle have a high “tinny” sound to them…

Try it see what you get… Most people either tack weld them back into place…or rip them off the vehicle.


If its up front…YOu have several heat shields there…on the Cats…as well as the downpipes… Have a looksie…

Is the sound TINNY? Like a thin piece of metal rattling? Or is it different type of sound…heat shields are so distinct to me… Hard for me to describe I guess

I just had someone clamp the heat shields. Noise is still there…

AH…OK… Geez… not many other things rattle quite as well as the heat shields… There are MANY of them…you know…

Is this a 4 cylinder or a 6?

AND I HOPE you arent confusing a rattle…with a ROD KNOCK…or VALVE TAP… Is it a hollow sound? DOes it seem to emanate from a deep place?

From what I recall those vehicles are prone to DRINKING OIL… Burning it actually… How is the health of the oil? Is it changed regularly? etc?

GUYS…Arent these vehicles ACTUALLY IZUSU’s rebadged?

Using HondaBB’s suggestion of pushing it while sitting still, is the noise there, then, too?

How about if you just rev the engine while sitting still, preferably in Park or Neutral?

If so, then it’s not in the driveline. If you can reproduce it while sitting still, you can locate it. Pop the hood, get under it, or whatever. Apart from getting a warm spot on your hands from the exhaust system (wear gloves and a long-sleeved shirt), you can poke at stuff that’s not moving. You won’t hurt anything unless you get under there with a hammer and start bashing away. Push and poke at stuff until you find the bit that’s moving.

Just because someone clamped the shields, doesn’t mean they got them all.

This is shooting with a blindfold. You’ve apparently had several different people look at the vehicle and give you their take on what the problem is. Apparently some work has been done on it as well (at least the heat shield).

So how about you give folks some details on what has been said about the noise by people who have actually had a chance to hear it and look at the car.

Indeed…did any of those folk say anything like…“You have a rod knock” or … “Maybe its valve lash” We really are in the dark here… More info would help greatly

From my experience…I have heard a LOT of Izusu Rodeos with valve tap issues…probably stemming from their tendency to drink oil… They then get low and the operators don’t realize they have nearly no oil in the engine…

Wow, thank you all for your helpful suggestions and hints.
The noise is more of a ching-ching, not necessarily hollow, or deep.
I’ve had them tell me it was the heat shields, to which they did the test (lots of gas, with brake as Chaissos mentioned). And then they told me that the rattling they could hear was the heat shields that they replaced. (I believe they clamped three of them.) So, you’re right-- it could be others.

However, another mechanic, tells me that the rattling is from the catalytic converter and needs to replace that system.

And the final mechanic told me that the innards would fall out on the interstate, and that the part he wanted to replace was “known” for being bad in Passports/rodeos and so, he wanted to put in a part with a lifetime warranty so if it gave out again, it would be replaced for free. This particular part (and I know you all will hate this), I can not find the paper where I wrote it down. It seemed like complete Greek to me, but I made him explain where it was in the car, and he described it as being underneath the main body of the car, and I assumed part of the tranny.

I really hope this helps…

Rod Knock was definitely not in the running. I know and am familiar with that term.
Valve lash does not sound familiar either.

The car is kept in reasonably good shape. I agree it has guzzled a lot of oil, but we tend to keep on top of that pretty well.

We are not able to reproduce the sound on the ground, in neutral/park/etc.

Was the “part” he wanted to replace perhaps and engine or transmission mount?

What was someone wanting to charge you $4000 for? The most expensive item in there is the catalytic converter & even that shouldn’t come with a $4000 estimate.

What kind of shops are you going to? Many people use dealerships (lots of $$ for often average skill & service) or large chain-type “auto care” places (often low in competence & high in selling). You need a neighborhood garage - the kind of place where the person overseeing the work has their own name on the sign out front.

Everyone here is just shooting in the dark, since we can neither hear nor examine your vehicle.
However, I will throw out another possibility, namely–spark knock–also known as “pinging”.

Noises are hard to describe, but the best way I know of describing spark knock is to compare it to the sound of a few small pebbles rattling around in a tin can when it is shaken. If your noise is akin to this, then I think you should add “spark knock” to the list of possibilities. And, yes, this can cause severe damage to valves and pistons over an extended period of time, so it is not something that should be ignored.

The possible causes include:
A stuck EGR valve
Carbon deposits in the cylinders
Old, eroded spark plugs
Timing that is too far advanced (Assuming that your timing is adjustable, which I don’t think it is)
An engine that is running too hot
Using gas of too low an octane

Normally, you will only hear spark knock if you put the engine under load, as when driving uphill, or when accelerating. In extreme cases, you might even be able to hear it while the engine is idling, and then it would likely increase as you put the engine under load.

Found the missing paper! Mechanic #3 advised that I needed to rubuild or replace the Transfer Case Bearing (output); advising a remanufactured Jasper part

Could a Transfer Case Bearing output be causing this type of sound, and if so, what is an appropriate estimated cost for such a repair?

OH Woah… THAT part wouldn’t make the sound unless you were moving… If you hear it while stationary then that isnt the issue. Sometimes Catalytic convertors will rattle internally when the honeycomb material gets damaged…same thing with mufflers…when their internal baffles rust and separate…then they rattle around inside the muffler casing…same with Cat casing