[goesto11]

I have a 92 L sedan, with 50k miles on it. The car is great except for the rough engine at about 1250 rpm. I don't think it is the transmission mount, because I don't have any of the other mount problem symtoms (clunking during corners, shakes felt in shifter...)

The engine is smooth as silk at all other rpm's.

Since 1250 are the rpm's that seem to be hit the most (30 - 40mph), I encounter the vibrations all the time during stop and go driving.

The one thing I haven't tried yet is to change the tranny oil. Would that really make a difference at such a specific rpm range?

any one else encounter this? any ideas on what to try next?

 

[KNLNGUS]

To my knowledge... all 3.2 experience an imbalance at that RPM range - some engines - do not have it (which I question) but anyways... Honda did put out a service bulletin long ago about this issue and normally you will feel it inbetween 1300 and 1700 - although yours may occur around 1500 and dissappear at 1600.

Anyways, I've talked with 3 people who swore up and down that thier 3.2 didn't have a vib and I opened thier eyes.

KNLNGUS

Another couple things before I forget... If you call an Acura service department and explain your thread... they will tell you that it is an "issue" with the 3.2 AND that there is no fix.

I am always for fresh fluid in the trans (and while you are at it, drain, replace filter, and refill the engine oil too), but that won't rid the problem.

 

[hauch]

engine vibration

Yeah - we just addressed this again in another thread that started about the tranny mount - which undoubtedly needs to be replaced - but is not a fix for this very specific vibration.

My question: Is this inherent in the engine design, thus they all do this, and they all have since they were new?

-Or-

Is this problem only found in a subset of our 3.2G2 Type I engines -
does it show up at a certain age?
only after certain types of service? (ie. t-belt)
only using certain blends of fuel?
only certain version of software/firmware in the ECU?
tune-up specs, plugs, wires, timing?

Seriously did they all do this by design since they were new?

 

[92coupeon18s]

probobally desing if everyone has it. I know mine is rough when i put the needle at arund 1300. It might just be the way the valves and what not are opening at that time and it is rough. Nothing to worry about just get through that RPM rang fast and u wont feel it

 

[PSA]

could be why there is a balancing shaft on the 3.5 RL

 

[KNLNGUS]

PSA... you are a knowledgeable and wise one aren't you!

I tried to keep it simple... laughing...

You know... all G2s have this rough idle that varies on the RPM range (some reports are coming in at 1250) so from say 1250 to 1800 but they are really noticealbe within a given 100-200 rpms within that 1250 to 1800 range .

I will say this. Although when you first drove your G2 off the lot... it had a vibration (same as it does now) - but was probably less noticealbe because it was brand new. Now that our Legends are begining to show and feel their age (with years, mileage, and therefore... overall wear) - you are probably more astute.

Now hauch, some of the things you pointed out...

certain blends of fuel and plugs (in addition to other things)

can cause your engine to idle and run rough.

Now... if you live near San Diego and you cross the border for some of that 75 cent gas... then you know what I'm talking about... Your thinking its okay cause you are selecting HIGH GRADE at the pump and ALL that gas is 50% low grade fuel 25% taquila and 25% water.

Now... if you don't think fuel matters... pump some of that stuff in there and lets talk about engine vibrations.

BTW... a fresh set of plugs (like Irridiums) does calm things down a hole lot.

KNLNGUS

 

[Steve91LS]

The rough idle @ 1250 rpm is 'normal'. I had my rear trans mount replaced a year and a half ago and it still has been rough, so it ruled out the mount. Its not a major problem though, more of an annoyance. The rough idle only seems to be in the 1250 to +/- 1350 range though, you dont notice it at all while driving.

 

[goesto11]

I did just put new plugs in, and it made no difference. The vibrations really are not that noticable, more annoying than anything. It just kind of bugs me to think that my nice car is not as "smooth" as my wife's minivan (Honday Odyssey w/ a 3.5).

I'm thinking it may have something to do with the 90 degree design of the V6. GM made a 90 degree V6 a few years back (the 231 ci) and they had more trouble with it than you can shake a stick at, one of the problems being vibrations. Balance shafts do help, but I'm thinking that in the case of our Legend 3.2 they didn't get it quite right. I'll just have to live with it.

 

[LIMEY]

Got the same issue on my '91LS

Yep !

I have the same issue - before checking the forum I was going to pump in some niuce clean tranny fluid thinking that would take care of it - NOT SO I hear you saying !!!!!!!!!!!1

Well - since I just got the car - I problably should do it anyway - while I'm replacing the rear tranny mount !

YES-YES and the filter !

Question - any particular flavor of tranny fluid they prefer ?

Thanks,

Limey.

 

[Roger]

i dont understand what rough idle at 1200 RPM everyone is talking about ?? iv tryed to find this and i have no such symptoms


our tranmission has a filter i though it dident??? where is it?

 

[vrb747]

Is this a common prob....

Coz I dont see this on mine either

What I do see is once in a blue moon the whole car vibrates crazily whenver Im completely stopped. It then keeps doing it for the entire ride, only when not in motion (neutral & D4)

The next time I drive this symptom disappears. Does anyone know what this is ? How expensive ?

BTW 93 LS Coupe 142000 miles

Thanks

 

[goesto11]

It is not so much a "rough idle" as a slight vibration in the engine that is transmitted to the whole car at around 1250 - 1400 rpm. It really is not that noticible. I've noticed that only people that really "feel" their cars notice it. For example, my wife who knows little about cars and could care less about them doesn't notice the vibration at all. Also, if you have the radio on loud, you probably won't notice it, that is how slight it is. But having driven many nice cars with smooth engines, I noticed the vibration the first time I drove the car.

I'm going to drive my friends 93LS and see if he has the same issue. I'm pretty certain that it has to do with the 90degree layout of the V6.

 

[andwhat03]

Maybe the rear mount isn't position properly

I have this vibration as well with my 95 6sp with 145k on it. It was vibrating bad when I bought it, found out the rear trani mount was bad, replaced it, now the vibration is not as bad. The vibration happens from 1500-1800 for me.

I replaced the mount myself, and I noticed that the position of the mount to the engine was adjustable. Meaning that the holes on the mount for the bolts are larger than the dia of the bolts. NEways, Any of you guys out there have the Helms or dealer book for this car? I need to know if there is a specific way to align the mount to the gearbox.

 

[KNLNGUS]

Before I decided to accomplish this task (for my own vehicle) I brought my helms manual in to Karen Radley and talked with a tech about the job because I had that concern you mention.

Obviously your rear transmission mount does not carry any load.

The engine/trans combo should be resting perpendicular to the cross beam. Once this is achieved... the mount should be secured to the undercarriage and the rear trans braket should be positioned to the rear of the trans so that engine/ transmission (in its level and resting position) causes ZERO tension on the rubber of the mount.

Now... the tech did indicate that over time and with stress that is is common (and probably the intended desire) for the the braket to find a resting point in both the trans mount (that bolts to the undercarraige) and the trans mount bracket that bolts to the rear of the transmission.

I hope this helps explain things a bit.

 

[Crazy Cuban]

our tranmission has a filter i though it dident??? where is it?

I think all trans. has one .. the only one I seem to remember replacing is on a AT .. I have a MT and will be doing the flush and fill (maybe 4X in another thread) but would definitly like to know if there is a filter so I can replace it.

Sorry to get off subject but made me start thinking about it again.

BTW .. I also felt mine at about +/- 1500 rpms that it had a little shake but after I but on a CAI and replaced my plugs with Denso Iridiums and oil change. . it went away some to where it was hardly knowest and now that I just did the Rear mount I can't really feel it unless the engine is cold or when it's REALLY cold out

 

[csamos2]

The rough idle @ 1250 rpm is 'normal'. I had my rear trans mount replaced a year and a half ago and it still has been rough, so it ruled out the mount. Its not a major problem though, more of an annoyance. The rough idle only seems to be in the 1250 to +/- 1350 range though, you dont notice it at all while driving.

By the way, Steve. Your ride is hot as hell. Those rims loks tight. The next set of rims I get wil probably be gunmetal, like yours, but the polished lips makes them looks awesome.

Nice job and great taste.

 

[csamos2]

Tranny Mount

I'm a new G2 onwer (had a G1 for awhile), so excuse my ignorance.

What is the suggested repair for teh tranny mount? Should it definitely be replaced? if so, at what mileage? What symptoms indicate it needs replacement?

 

[mocca]

You know what guys, I've never noticed the rough engine at 1250 rpm until I read this post and carefully try to hear the noise and it is there at about 1250 rpm. I tried wrev up the engine a bit when car idle to hear it though. When the car is running, I can barely hear the noise.

Mocca

 

[KNLNGUS]

Mocca... are you sure you mean hear as opposed to feel. The rough engine idle occurring usually between 1250 - 1800 RPM range and at a 100-200 RPM spread can be felt FAR easier and heard.

csamos2, the ONLY repair for a broken tranny mount is... the purchase and installation of a brand new one. One really can not pin down a mileage (or year) that a tans mount will fail - its a matter of diagnosis... a thud noise w/ hard acceleration, braking or turning, manual trans shifter feeling like its traveling- in turns, excessively harsh auto 1st to 2nd shift, excessive engine vibration.

 

[bigdad]

all three of my Legends had it, even when new...slight roughness at about 1250-1350....My own thought is valve lift and overlap design are the cause for this breathability issue at low rpm....it is not noticeable during normal driving, as this rpm range is hardly ever used at constant speed, but merely transition through it.