whinning noise from engine when driving at low mph

I am trying to find a exact problem that the car is having for last few weeks and now i am sure that i know the symptom and needs advice on what can be the possible issue and how to fix:
" After i drive the car on inner roads for about 30-45 min at <35mph, engine start making knocking/rattling/whinning continuos noise and i can feel the shake in pedal and steering and it feels like just to stop the car. This does not happendif drive less than 30 min on inner roads and never happens on highway driving for 2-3 hrs at >65mph"
Any advice or suggestion will be appreciated.
car: 2001 i30 having about 56k miles

Thanks
--rubs

...about 30-45 min at <35mph, engine start making knocking/rattling/whinning ...

At that speed, engine compartment is hottest. (IF u want to know exact temps, then buy 10$ home temp gauge w large range, with a 10 feet wire, place it under hood, try different locations. Tape it. Route wire through door, gauge inside. Drive & measure)

Smtg 'overheats' under hood. In other words, there is a heat related problem. If plugs have never been changed, thats your problem. Next most common problem is coilpacks. Theyre electronic de-vices w/o any cooling = most stupid feature a car can have, after CAT.

After plugs have been replaced, an IF still faulty, Diagnose: When fault is ON, disconnect one coilpack after anoher. The one(s) making no difference in engine sound, are bad. Buy new ones via net, replace. (if u are to keep the car for next 60kmiles, also buy the more platinum plugs, worth the price)

Note: the "whinning noise from engine when driving" is NOT caused by either sets, u must first locate the sound source. Oftentimes needs a mech familiar wit just that vehicle type...

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Plugs are never changed since infiniti recommend changing them at 105k and now the car does not have even 50% of that miles.
Should i just change them as they are not that expensive to change or spend more time and try to find the exact issue?


At that speed, engine compartment is hottest. (IF u want to know exact temps, then buy 10$ home temp gauge w large range, with a 10 feet wire, place it under hood, try different locations. Tape it. Route wire through door, gauge inside. Drive & measure)

Smtg 'overheats' under hood. In other words, there is a heat related problem. If plugs have never been changed, thats your problem. Next most common problem is coilpacks. Theyre electronic de-vices w/o any cooling = most stupid feature a car can have, after CAT.

After plugs have been replaced, an IF still faulty, Diagnose: When fault is ON, disconnect one coilpack after anoher. The one(s) making no difference in engine sound, are bad. Buy new ones via net, replace. (if u are to keep the car for next 60kmiles, also buy the more platinum plugs, worth the price)

Note: the "whinning noise from engine when driving" is NOT caused by either sets, u must first locate the sound source. Oftentimes needs a mech familiar wit just that vehicle type...

.

... try to find the exact issue?

At least first check them out how they look, at least they should look equal. Go to ngk.com to 'read' plugs.

As u know, anything may break before expected time. When problem is intermittent, its worst kind: no way to know if problem is cured, and if it is, because u changed smtg, or just because u touched smtg (if you swap plugs or coilpacks).

With this kind problem, DIY is the only reasonable way to proceed. If u want to keep costs down, buy 2 cheap 2$ plugs(or whole set just for tst purposes). Swap places if problem re-occurs. If no hlp, buy 2 coilpacks, one for fron, one for rear, do likewise.

No warranty that plugs, coilpacks is THE issue. Probability is high... It may still be that u have other problem(s), juts bad connection. If not, then its time for sensors swap, one at a time. Goto junkyard for cheap troubleshoot parts. Testing the sensors (alas) will not hlp too much, as they surely will work when tested... (My guess is that there are 3pcs O2 sensors, by modding connector, u may be able to tst all three with buying only one, swapping)

Bad connections and whattodo: http://www.cardomain.com/ride/748507/14

You may also try to use hairdryer to simulate heat effect on parts (coilpack, MAF) while idling. Careful.

Manual will be worth it; I think u may survive with 2k2 maxima manual from http://www.phatg20.net/

Problem is still there, but today i notice that after driving on highway for >30 min when comes to inner road the engine was still making loud noise, so the problem is not just driving on inner roads for long time but on the highway also but noise only comes after driving at <35mps

At least first check them out how they look, at least they should look equal. Go to ngk.com to 'read' plugs.

As u know, anything may break before expected time. When problem is intermittent, its worst kind: no way to know if problem is cured, and if it is, because u changed smtg, or just because u touched smtg (if you swap plugs or coilpacks).

With this kind problem, DIY is the only reasonable way to proceed. If u want to keep costs down, buy 2 cheap 2$ plugs(or whole set just for tst purposes). Swap places if problem re-occurs. If no hlp, buy 2 coilpacks, one for fron, one for rear, do likewise.

No warranty that plugs, coilpacks is THE issue. Probability is high... It may still be that u have other problem(s), juts bad connection. If not, then its time for sensors swap, one at a time. Goto junkyard for cheap troubleshoot parts. Testing the sensors (alas) will not hlp too much, as they surely will work when tested... (My guess is that there are 3pcs O2 sensors, by modding connector, u may be able to tst all three with buying only one, swapping)

Bad connections and whattodo: http://www.cardomain.com/ride/748507/14

You may also try to use hairdryer to simulate heat effect on parts (coilpack, MAF) while idling. Careful.

Manual will be worth it; I think u may survive with 2k2 maxima manual from http://www.phatg20.net/

Problem is still there, ... driving at <35mps

problem is?
- whinnnoise
- shuddering engine

-> The tranny oil is warranted 2-30kmiles. Time to change:
http://www.cardomain.com/memberpage/748507/24
-> swap plugs, coilpacks. Theres no such thing as free miles...

.

Thanks a lot for all the replies.
More of a shuddering engine and it feels so bad (feels like it will explode)
That link is not working, transmission oil was changed at 30k and since infiniti recommends changing every 60k so was thinking at 90k but may be need to do early.

problem is?
- whinnnoise
- shuddering engine

-> The tranny oil is warranted 2-30kmiles. Time to change:
http://www.cardomain.com/memberpage/748507/24
-> swap plugs, coilpacks. Theres no such thing as free miles...

.

...More of a shuddering ...That link is not ...

CarDomain has also been stuttering long, too big growth ? maybe... hopefully get it up. If no work done, keeps stuttering.

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