o_nate

I've noticed a couple of times on a certain hill, when I'm heading downhill and I come to a stop at a stop sign, the engine idle suddenly becomes very rough and the car starts shaking a bit. I have the 5AT. I was wondering if anyone else has experienced a problem like this or might know what would cause this? Most of the time the idle is reasonably smooth.

o_nate

Also: this happens after the engine is fully warmed up.

TSXEuphoria

Mine has the same problem.
I think shaking/vibration is worse at driver side. Try to feel the passenger side dash or door handle they don't shake as much as driver side.
Mine idles roughly when rpm needle goes under 750rpm.
and also worse at uphills.
I dunt know if this is normal.

MarkPinTx

A/C on or off? I note that my idle goes from very smooth to a tad rough when compressor is on. Had kinda hoped for a smoother compressor in my first ricer

ClutchPerformer

Are you guys using the sportshift thing? Is it in too high a gear as you come to a stop? I can't think of a situation where an automatic transmission would let itself get below 750 RPM. It's natural for the engine to shake under load at speeds that low (I bet all the 6MT owners know this). It's weird that it would happen on an auto.

503TSX

haven't had that problem, but did notice that if you are going downhill, and you lightly hit the brakes, gotta expect the tranny to downshift, cause it will... then you really slow down... lol

biker

Does it still shake if you put in neutral?

o_nate

This doesn't happen while I'm decelerating. It happens after I come to a complete stop. I think the AC may have been on when this happened, so that may have contributed to it.

I haven't tried putting it in neutral. I imagine that would help.

It hasn't happened very often. Both times it was a few minutes after I got off the highway after about a 50 mile drive. On a certain downhill slope there is a series of stop signs, and when I come to a stop there, the engine starts shaking. I was wondering if perhaps the incline may have had something to do with it too. The car is pretty new still (only about 1500 miles). Should I have the dealer check it out?

I'll keep an eye on the RPMs next time too, to see if it falls below 750.

slo007

I've seen it at 500. Short time periods, though.

Schizm70

stupid question: You are using 91 octane, or higher, fuel o_nate?

clutchperform, the sport shift will automatically downship you if the revs get too low to prevent stall. It won't upshift for you though

(wishing I had gotten a 6MT)

o_nate

Yes, I always put 93 octane in it.

This morning I looked at the RPMs when the car was idling after it had warmed up a bit, and they were at 650. Is that too low? Should I have the idle tuned up a bit?

Schizm70

just wanted to be sure o_nate...no offense. There was a thread full of people discussing there use of 87 octane fuel & it was like nails on a chalkboard to me.

My TSX idles at 700rpm and stays there, unless the compressor turns on or off.

calgary_tsx

I have a 6MT, and use min 91 octane fuel, and I get this sometimes too, especially when the weather is hot. It drops to about 725rpm, but usually only briefly than adjusts back to 750. This NEVER happens in winter, as the motor probably doesnt warm up properly, and so idles usually around 900-1000.

dom

I definently don't have this problem on my AT. I WAS experiencing a vibration when stopped and in park, but even that has gone away.

Allow the engine to get broken in some more. That may smooth things out.

Creaminz

My car at 16000 miles, and now I am having same problem. Stop sign, red light, AC on/off, I can hear this rough idle. Mostly at night time. HATE!!! Rattles!! Squeaks!! and now...ROUGH IDLE!!?
GOD HELP ME!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Analyst7

I too have the engine vibration (5AT)- at approximately 950-1100 rpms - check for yourself. I took my TSX to Santa Monica Acura for service and they told me this vibration was in "normal tolerance range," per the factory, even though my service advisor felt the vibration as well. The dealer checked the engine mounts and told me they were fine. My advisor said to wait until there is a service bulletin. The problem is more prominent with the A/C on. I have a long commute each way and just letting off the brakes to allow Drive to pull the car in slow traffic can heighten the vibration. But it is sporadic - it comes and goes, and I'll say it seems to be getting a little better over time.

forestsoft

I wonder if it has something to do with the oil in the intake..from the PCV valve. Maybe some Gumout?

o_nate

I've observed this problem some more. I found that it actually doesn't happen on the down incline, but just after the road flattens out again. There is a series of a few stop signs going downhill. At the bottom of the hill, when the car levels out again, the idle gets very rough for a few seconds. I'm usually going about 5 mph at this point. Very strange.

Analyst7

Onate,

You should have the dealer check it out. The more people that report a specific problem with their car, the more likely someone from corporate Acura will listen. My service advisor told me it's a problem between 950-1100 rpms, but doesn't have a fix for it yet. I can feel the roughness come and go when I am inching along in a commute, and is only really apparent when the A/C compressor is on.

Clutch performer, it almost feels like it's in too high of a gear - that's exactly what it feels like. Yet, unless I'm totally mistaken, I'm still in first gear (in my 5AT) when it happens.

If anyone has/had a savvy mechanic offer a fix for this, please let me/us know.

Thanks,

Analyst7

JTso

iTrader: (2)

Hmm... I'm suspecting a problem with the injector duty cycle at that particular rpm/load range. The dealer should be able to do a datalog and find out what the problem is and reprogram the ECU accordingly.