4Litre engine trouble???

[SuperRoo]

Hi guys, a big hello from a newbie, hope someone could advise on my "little" problem.

I'm getting a "rattly" type noise when my Jeep is either in park or idling at the traffic lights. Under load or whilst driving (accelerator depressed) there doesn't seem to be any noise. The actual noise sounds like it is under the vehicle, but when the bonnet is lifted it sounds as if it's in there -"somewhere"

My local garage having taken the pulleys off, said they traced it to inside the engine, but still don't know what it is unless the engine is stripped!!!

Hoping someone may have had a similiar experience and (praying ever so deeply) it is a very inexpensive remedyray:

The vehicle is a LHD Cherokee Lerado 1988 model, with automatic transmission, 4litre petrol.

 

[90growler]

Broken or loose motor mount? Is it a clicky-clack sound?

 

[90Xjay]

"bonnet", "petrol" I love it!

Greetings from accross the Altantic!!

What is the milage, does it smoke at all?

If you can take a long peice of wood, say a broom handle, you can (I know this sounds funny, but bear with me) take the broom handle hold one end against your ear and press the other end up to the valve cover(tappet cover) and see if you hear the noise more intensely, do the same thing for the oil pan. This method works best if you have a long peice of metal, like a long socket extension, but most people don't have one that long, so a handle works well also.

 

[Bounty__Hunter]

There is a knock sensor on the driver's side of the engine block, above the oilpan. Make sure it's intact and working.

 

[SuperRoo]

Thanks guys for your suggestions.

She is 120,000 miles, golden oil in colour and doesn't smoke - in fact a very smooth ride, just this noise is abit of a worry (until I know how lethal it maybe to my wallet) as I'll be driving her from London to Poland and back again mid July

 

[Laph]

rattly noise, like a loose guard? Check your O2 sensor and make sure its not loose, mine was loose and rattled for the longest time before i finally found it. If it is loose just take a wrench to it and tighten it up It was the o2 sensor next the transmission. between the cat and man

 

[90Xjay]

If it makes you feel any better, alot of us have alot more miles that you have and no major engine problems, alot of 4.0s out there with over 200K miles on them running strong.

 

[Laph]

wow an 88 with only 120k miles? :lol: I have 153k on my 99 IL6 I run full synthetic in it though, but still runs like the day I got it.

 

[Jeepr]

This may be overly simple, but would it have a catalytic converter on it?

 

[90Xjay]

This may be overly simple, but would it have a catalytic converter on it?

It should have came with one esp being that late model.

 

[Jeepr]

I didn't know if they had them over the pond...

If it does, wack it with the bottom of your fist like you were banging on the bar and see if it rattles (best to attempt when cold). They rattle pretty good when they start going bad.

 

[dingus]

yeah, my guess would be the CAT as well... a band-aid fix is just to take a couple long screws and screw directly thru the cat. IF thats ur problem, that is. does the noise go away when you are accelerating? if so, i'd def. say its the cat. if it does get worse as engine speeds rise, i'd say it could be something in the bottm end.

 

[lethaldose]

maybe a loose rocker arm or something in the top end ... one guy suggested a broom stick which is a good way to listen .. but you can actually pick up an automotive stethescope *spelling is way off i know* LOL for under 20 bucks usually and listen more in tune ... and locate the prob ... if its a SLAP sound its in the bottom end but if its higher pitched its in the top end

 

[90Xjay]

You know it could be just a little harmless piston slap.
I wished we could actually hear it.

 

[mufflerman]

i had the baffles on the inside of the vavlecover come off and it sounded like a bad lifter ?

 

[SuperRoo]

Just thought I'd give an update on my "little" drama. After having it up on the hoist we could hear a very large tapping sound coming from the sump. Likely suspect is a gudgeon pin (or in American, a piston pin). Now I'm waiting for the verdict, she is back in today to have the sump dropped, to confirm suspicions, (maybe the head off) and then costings on repair or replacement with another engine. Doesn't look like I'll be able to get out of it very cheaply at all

 

[SuperRoo]

And BTW, the mileage is actually 130,000 miles, (slight typo in my earlier post)

 

[SuperRoo]

This is really doing my head in. After checking out the engine, the garage has been told by Jeep that it is the gearbox!!! Apparently, a vacum pump in the gearbox has given out and is sending a vibration through the engine??? I don't know waht to believe. Anyone heard of this before? Cheers guys for your advice so far, but this is supposed to get me to Poland AND back in 2 weeks time, i'm just lost for answers...