Idle Vibration, Reduced Power, etc.

[89fuelie]

It would appear that my car, like all automatic equipped 3g's it would seem, has a ridiculous amount of idle vibrations. I changed all four motor mounts to no avail. Little or no vibration in Park, reverse, or neutral. Only in the forward gears does all heck break loose. The whole car shakes, especially the steering wheel. It isn't running poorly, (no misfire, etc) but it just shakes like hell. My roommate has taken to calling the car Michael J Honda, it's so bad.

Also, this is possibly the most sluggish thing I've ever driven! It has almost no power from a dead stop, or at highway speeds. I'm going to check my timing, bypass solenoid, maybe the throttle body and/or IACV. I'm also going to try to upgrade the grounds, because electrical loads seem to exaggerate the problem. Also, do these cars need a valve adjustment? My car has ~135K on it and I can't find when it was last done. I've just got fingers crossed that it isn't a torque converter. Any help would be appreciated. :sad2:

ALSO: I bracket race my car at the 1/4 mile track weekly, and sometimes out of nowhere it's like it gains 15-20HP or so. It will run 18.8 all night, and then out of nowhere it will run 18.40! And then the next run will be back to 18.8 range. This is with little/no change in temperature, wind, etc. This makes me feel like the power problem is sort of intermittent, which is even more confusing.

[2oodoor]

I would remove the dist. to clean up and lube up the plate so it moves really easy when the wieghts kick out, then assure the vac advance works good then subsequently install the dist and set timing to a few degrees above oem specs and try it out. If it pings then retard till it stops, if it dont advance till it starts then back it off a few degrees.

Also would run some bg44k fuel inj cleaner or compatable lucas or seafoam cleaner in the tank.

not saying that will fix it but from what you describe it sounds like a good idea to start there.

[Buzo]

Vibration is caused for a lean mixture. I am able to precisely control the mix in my car and as soon as I lean it out it starts to vibrate like crazy. Unfortunately I can not tell you what can cause a lean mixture in this car, but to fix the vibration, I would start checking the air/fuel mix related parts i.e injectors, fuel pressure, filters, idle valve, etc.

[89fuelie]

I just realized I never mentioned it's an 89 LX-i. Thanks for your input, I will check the injectors to see if they are firing, and keep a sharp eye for vacuum leaks. Good idea with the distributor< I will have to check that too. I'm off for the rest of the week, so I will be taking a close look in the next few days. It's times like these that I miss my carbureted and emissions exempt cars! So much less to deal with.

[CzEcHy]

Damn, ill trade you my 88 LX with a weber 38 for your FI accord.. lol

[89fuelie]

Damn, ill trade you my 88 LX with a weber 38 for your FI accord.. lol

If I didn't live in California, I might take you up on it! The emission overlords in this fine state have decreed anything that isn't factory spec (even an improvement) isn't allowed. Basically, it doesn't matter if it exceeds cleanliness standards, if it isn't stock - too bad. I can only imagine the hijinks and tomfoolery that one would have to go through to get any carb'd car to pass in the Golden State. From my experience with BMW 2002's, the 76 is just a disaster to be avoided at all costs! Apparently Lancia Betas wouldn't even pass when new unless leaned out. But i digress...

[2oodoor]

tomfoolery, wow I never actually saw that spelled out before lol

Dont forget the pesky hidden vac leak from poorly seating egr valve.

Also, a lot of these cars running around with incorrect valve timing caused by the confusion of which mark on the flywheel represents true TDC when T belts are replaced.

[Oldblueaccord]

It would appear that my car, like all automatic equipped 3g's it would seem, has a ridiculous amount of idle vibrations. I changed all four motor mounts to no avail. Little or no vibration in Park, reverse, or neutral. Only in the forward gears does all heck break loose. The whole car shakes, especially the steering wheel. It isn't running poorly, (no misfire, etc) but it just shakes like hell. My roommate has taken to calling the car Michael J Honda, it's so bad.

Also, this is possibly the most sluggish thing I've ever driven! It has almost no power from a dead stop, or at highway speeds. I'm going to check my timing, bypass solenoid, maybe the throttle body and/or IACV. I'm also going to try to upgrade the grounds, because electrical loads seem to exaggerate the problem. Also, do these cars need a valve adjustment? My car has ~135K on it and I can't find when it was last done. I've just got fingers crossed that it isn't a torque converter. Any help would be appreciated. :sad2:

ALSO: I bracket race my car at the 1/4 mile track weekly, and sometimes out of nowhere it's like it gains 15-20HP or so. It will run 18.8 all night, and then out of nowhere it will run 18.40! And then the next run will be back to 18.8 range. This is with little/no change in temperature, wind, etc. This makes me feel like the power problem is sort of intermittent, which is even more confusing.

valve adjustemnts listed for 12k miles. Not a bad idea to do it every once in a while.

does you car's torque converter have lock up mode? Its sounds like its stuck locked up.

18.8 in the quarter sounds very slow. most stock cars can run low 17's all day. You do have some to be gained someplace.

wp

[89fuelie]

valve adjustemnts listed for 12k miles. Not a bad idea to do it every once in a while.

does you car's torque converter have lock up mode? Its sounds like its stuck locked up.

18.8 in the quarter sounds very slow. most stock cars can run low 17's all day. You do have some to be gained someplace.

wp

Low 17? With a 5 speed I presume. I still expected high 17, or at least low 18. The valves are pretty noisy, gonna tackle that one tomorrow morning. Checked the bypass valve, it isn't opening. Gonna change the solenoid out and see. The timing is correct, but I don't know if the advances are working. The torque converter does lock up at about 45-50MPH. Honda dealer suggested TW sensor, going to change that tomorrow. ECU not throwing any codes. I am going to try to get the grounds done tomorrow, we'll see how far I get. I'm leaving around 1 for my grandparents house for T-giving, then I won't be able to look at it till Friday. Fingers crossed its short and easy!

[89fuelie]

OK, update. This morning I changed the oil and tranny fluid again, simply because it needed it. I also adjusted the valves, what a difference! They were all way too tight. Now it clicks a little bit, but the power difference is noticeable. Also notable was that the cam is not timed with the flywheel! When the last person changed the timing belt they must have put it on a couple teeth off. How hard is this to fix? Is it like changing the T Belt itself?

EDIT Looking more closely, it appears to be a couple degrees advanced compared to the flywheel. Would this give it more power? Or just hurt it in the long run? I'm looking compared to the white mark on the F wheel.

[2oodoor]

tdc mark on the flywheel is the barely visable scribed T and not any of the boldly visable marks which are only for using the timing light because they call for setting base timing with vac advance activated.

Having your lock up kick in at 45-50 sounds a good bit too early from my experience with these cars that would cause it to keep going in and out too easily and not appropriately.
Maybe not your case but a good way to tell when it is right to me is it will stay locked up at 60 until I move the throttle significantly down or up.

[Dr_Snooz]

If I didn't live in California, I might take you up on it! The emission overlords in this fine state have decreed anything that isn't factory spec (even an improvement) isn't allowed. Basically, it doesn't matter if it exceeds cleanliness standards, if it isn't stock - too bad. I can only imagine the hijinks and tomfoolery that one would have to go through to get any carb'd car to pass in the Golden State. From my experience with BMW 2002's, the 76 is just a disaster to be avoided at all costs! Apparently Lancia Betas wouldn't even pass when new unless leaned out. But i digress...

This is how you get your stuff through. (http://www.3geez.com/forum/showthread.php?t=76568)

[89fuelie]

tdc mark on the flywheel is the barely visable scribed T and not any of the boldly visable marks which are only for using the timing light because they call for setting base timing with vac advance activated.

Having your lock up kick in at 45-50 sounds a good bit too early from my experience with these cars that would cause it to keep going in and out too easily and not appropriately.
Maybe not your case but a good way to tell when it is right to me is it will stay locked up at 60 until I move the throttle significantly down or up.

Well, in that case then the cam is exactly on time! The lock up seems right to me, it pops in at about 48-50, and it will stay locked up unless I am accelerating. It only engages there on a flat, on hills not a chance. You describe a "better" lock up at 60, I can confirm that my car does that. The faster you go the harder it is to pop it out of lock.

After adjusting the valves there was a pretty big improvement, but I just did my bypass solenoid and WOW. There is actually some low end torque now! Apparently the valve stays open when the solenoid fails, so you lose all the bottom end. It will actually chirp the tires now! The rough idle remains, however. The stealership suggested replacing the TW sensor, so I think I will try to squeeze that in sometime in the near future...

EDIT I did check the plugs when I adjusted the valves BTW, and they did look a little lean. I'm going to run some injector cleaner through the next tank. Which one is best, from experience?

[Buzo]

... The rough idle remains....

You could just try to idle at higher RPM.

The tacho in the dashboard is not an exact measuring device, so it may read 1000 RPM but you may be at 900 RPM in reality. Also the fuel economy does not get really affected just by idling at higher RPM. I recall when I was trying to idle at 850 RPM at any price, but I learned that 1000 is OK.

[89fuelie]

You could just try to idle at higher RPM.

The tacho in the dashboard is not an exact measuring device, so it may read 1000 RPM but you may be at 900 RPM in reality. Also the fuel economy does not get really affected just by idling at higher RPM. I recall when I was trying to idle at 850 RPM at any price, but I learned that 1000 is OK.

I tried idling at a higher RPM, but it didn't work. :\ It reduced the vibration slightly, but it came back down to the old idle after I started driving it. I'm not too worried about economy, I just want it to work right!

I ran at the last track event of the year today, it went 18.181 twice in a row, and then 18.197! :beer: By far the best times I've ever gotten. Then it ran 18.33, which wasn't close enough to my dial in, but still a tenth better than the old best. My fault though, I did let the engine get warm before the run. :banghead:

I feel like it's running right where it should now, more or less performance wise. I'm also running Berryman's Chemtool through this tank of fuel, because I couldn't find the BG44K.

On another note, on the very last run my clock bezel not only fell off when I launched, but it used the edge of the dash tray as a ramp and flew onto the rear parcel tray! Always an adventure, the racetrack.

[2oodoor]

sounds great!
what exactly is it you are calling the by pass solenoid?

[89fuelie]

sounds great!
what exactly is it you are calling the by pass solenoid?

It's on 88-89 PGM-FI cars, it is the solenoid that sends vacuum to the butterfly valve that operated the dual stage intake manifold. There is a second shorter set of runners that opens at ~5k RPM's, and when the solenoids fail the butterfly valve is open all the time and you lose most of the low end torque. The factory service manual refers to it as the "Bypass Control System", which seems really vague to me. According to wikipedia its good for ~10HP and 8 lb/ft torque. Really changes the driving characteristics though. Part throttle acceleration and pulling away from a stop is dramatically improved.

[import racer]

I removed the black box on mine so I just hooked to manifold vacuum,could that be making mine run rough and idle low sometimes.Or should I just plug it off.

[1987AccordLx-i]

I removed the black box on mine so I just hooked to manifold vacuum,could that be making mine run rough and idle low sometimes.Or should I just plug it off.

hooking up the butterflies directly to the manifold is pointless.. at idle their closed... under slight accel the butterflies open up because of insufficient vac... its better off the just leave the butterfly dashpot alone... i removed my black box and i left the runners open all the time... im having timing issues so its a bit laggy... im WAY too advanced so it pings and stuff.. but its been like that since i bought it... but ima change the t-belt soon so ill re time it and see how it feels then... but with the black box removal.. i took off egr so i got a bit more response out of the engine..

[import racer]

So just plug the actuator is better than manifold vacuum is what you are saying.

[89fuelie]

So just plug the actuator is better than manifold vacuum is what you are saying.

If hooking it up isn't an option for you, personally I would just wire the butterfly shut. It only helps on the top end, and having it closed is much more helpful for more of the time. With the auto you really notice an improvement in pulling away from lights and part throttle acceleration with them closed. It does idle a little smoother with them closed, but not much. In my case, anyway. Manifold vac seems like it would not have the desired results.

[import racer]

Well I have my EGR blocked off too,just wish I could get rid of the rough idle at stop lights and engine light.

[import racer]

Well today I went and took a sharp right at a stop sign and it cut out again.It seems like it's not getting fuel when I make sharp turns.Any body have this problem before,I think I have a vacuum leak at the intake so that's probably what's causing my low,rough idle.

[import racer]

bump!

[import racer]

Well today I went back and did some more reading on the black box removal and from what I could tell my vacuum lines going to the distributor advance were backwards ,so I switched them but got a cel .Most of the pics were gone so didn't have much to go on,does anyone still have the pics of this removal.I thought rendon had some but couldn't find them.

[import racer]

What is the by pass solenoid and what does it look like.