Can anyone help solve this weird idle jump? 89LXI

[steve520]

https://youtu.be/kHnaJg7o7Yo

As you can see I get a weird jump only when coming to a stop while driving. It doesn't feel serious but it's super annoying.
Things i've done to try to fix these problems:
-Changed Plugs and Wires
-New Fuel Injectors and Fuel Filter
-Cleaned throttlebody, idle screw, and adjusted the fast idle valve
-Replaced IACV
-Adjusted Throttle Cable thought it was I thought too tight so I loosened to see if that was the problem didn't change at all.

I'm really out of ideas of what else to check or look for.

[MessyHonda]

did you bleed the cooling system? looks like you got a air bubble.

[steve520]

I tried to follow the bleeding cooling system tutorial but i felt like I was doing something wrong the whole time. I'll have to re-read and try again. I'll let you know how it goes thanks for the tip.

[steve520]

Just bled it following this tutorial http://www.3geez.com/forum/how/6572-how-bleed-flush-cooling-system.html seemed as if there were some air bubbles but not many. Had a steady stream before i tightened it back up still didn't have an affect on the weird idle change in the video.

[MessyHonda]

thats strange. you probably have a vacuum leak. Try spraying carb cleaner around the intake manifold to see idle changes. We had another member with the same problem and it was that the intake gasket was installed wrong causing weird idle fluctuations.

[steve520]

Just was researching found out it could also possibly be the brake booster check valve? I don't know if that's the problem or not will try to find a vacuum leak though. Thanks for the help Messy.

[steve520]

Well sprayed carb cleaner in the suspected areas, Intake manifold, Brake Booster, IACV, Throttle Body and no idle changes. I'm thinking its either gotta be the throttle isn't closing all the way, something the brake booster line, or possibly ignition coil. I was driving today and had this weird engine lag i guess is the best way to describe it. I would hit the gas and the thing would Rev really high and hard then drop back down it's a weird hesitation.

[Fenris]

How many miles are on it?

I ask because mine does the same, and I believe it to be the transmission starting to wear out.

Same thing happened on my 91 civic (automatic, too) about 6 months to a year before the tranny died. You'll probably notice a light hum from the transmission at low rpm (1k-2k) in first/second gear. It's only going to get louder as age and mileage increase.

At some point, you'll start to notice a metallic whine at low rpm and while idling. Once you hear that, consider the tranny toast, as you may only get a couple days/weeks out of it at that point.

Of course, that's all assuming it is the tranny. It could just be the throttle cable. Make sure it's adjusted to factory settings before you make any other diagnoses.

[steve520]

116k i figured it might be a possibility it was the tranny but it didn't do it when I originally bought it. I did change the tranny fluid. But it could be a possibility. I just wish I would have taken note of when it first started would have given me more of an idea. Also I believe another possibility could be the timing I took it in to get the timing belt done. I think that might have been when the problems started could that be a possibility?

[steve520]

Im just about to give up on this issue. I can't figure it out. Replaced the Brake booster line no change. Checked the tranny fluid not normal color and normal level. Looks like its a problem i'm just going to have to put up with.

[steve520]

Don't know if this could be the problem or not. Today my car was throwing a code 12 and a CEL on and off. So could this be the EGR valve causing this? Just want to know because it looks very difficult to reach.

[Fenris]

Definitely change the tranny fluid. The recommended interval on these is 15k or 1 year.

Make sure the timing is correct. When that's off, it throws everything else off.

The EGR isn't tough to get to. It's on the passenger side of the intake manifold. The pipe from the exhaust manifold is a pain in the ass, though. I wound up removing mine and blanking it off.

[steve520]

Thanks for the reply Fenris I meant to say Tranny Fluid was AT normal color and level meaning its still red/pinkish changed it about 1300 miles ago. I cleaned the EGR valve it was pretty gunky also replaced 2 coolant hoses that looked like total crap. Hopefully when I start her up she'll be good to go and yeah I gotta re-check the timing thankfully i already have to do that stuff anyways since i have an oil leak around the oil pump somewhere.

[steve520]

Well fuck cleaned the EGR bled the cooling system again no change at all. Hopefully i got rid of the stupid check engine light from it though. My last guesses are Tranny, Mysterious Vacuum Leak, or Timing. I think this stuff started after i got my timing belt done so hopefully it will resolve when i re-do.

[conozo]

Its not just downshifting is it? or downshifting hard. What happens when you put it in neutral then slow down slow and slow down fast?

[steve520]

Definitely not just downshifting. I think it may have something to do with the timing but not sure. Because before I had my timing belt done it didn't do that at all. So i'm thinking its something with that. Also it doesn't matter what speed i'm slowing down at. If I slam on the breaks and come to a short stop it does the same amount of idle raise. If i let it coast and come to an easy stop it does the same thing. It's weird though because when im in Netural. I'll rev and it will come right down like normal no rise or anything. I'll also put it in neutral and do the samething and then brake after I rev still doesn't do it. It literally only happens when its moving.

[conozo]

Any chance you can take it back to where you had the timing belt replaced and have them time it again for you.

Also i want to confirm you have checked for vacuum leaks. Spray some carb cleaner on vacuum hoses and where the intake meets the head.

[steve520]

I don't think so it was awhile ago. I think I might just have to do it myself. Yes checked for vacuum leaks around the intake no idle changes. Also noticed something today again after I drive my car somewhere leave it sit for about 15-20 minutes comeback and when I start it it will idle awful. It idles between 0-1000 but it eventually dies sometimes I have to give it gas to keep it alive. Don't know if this could be related to my problem. To correct I grabbed another Main Relay from the Junkyard, but it seems like it had no affect on the damn thing maybe both are bad? If I could correct these two problems I'd love this car.

[Liamk182]

Hi guys, just bought a 1989 Honda Accord LX on Tuesday, 122k miles, Manual and so far have noticed this same idle issue, and also appear to have an oil leak (just ordered a new oil filter base gasket today) so will be paying close attention to this thread. It's my first car so will definitely be a baptism of fire!

[2oodoor]

Op that looks somewhat normal to me, its the tranny downshift to assist braking. I will say these cars usually dont have such an antimated downshift upon stopping so I would say the tv cable needs slight adjustment. A super hi idle speed will show the same thing if you watch the tach as you pull to a stop.
Fwiw anytime you improve the tune, the tv cable will need tweeking because your throttle positions change because not as much throttle is needed to make motion and winding gears out is less necessary in normal driving.
Extra whurring and whining could be timing belt too tight or the belt tensioner bearing wasnt replaced

[steve520]

I messed with TV cable once before but maybe I didn't do it right the first time. I adjusted it by the How-To Thread posted on the site and Had that weird idle jump on top of another jump. So I turned it back down to where it originally was the first time. I'll try screwing with it again. I do think the timing still has some sort of issue with this because it never did that before. And if I recall I didn't start cleaning the Throttle Body, or EACV until this problem had already started I figured that is what was causing it something clogging it. But will check TV Cable.

[ShyBoyCA6]

well your dumping money in the car which is not good. when this car is doing that weird jump does the engine jerk or downshift? please make another video of this car on start up and when driving without looking at the tach. i suspect a bad ignition coil or pick up for this matter if its just the tach jumping around and not jerking.

[steve520]

I don't plan on dumping much money into it most of the parts i've gotten for it were junk yard parts anyway. But i'm gonna have to fix this stupid oil leak if I want to park it in the driveway. I plan on doing this work myself thankfully i've got a good idea of what I need to do. But yes I will make another video on it startup and driving again. I'm really not sure if the engine is jerking or not it just feels like it's trying to lunge forward when it revs. But on cold startup it acts fairly normal. I'll try to get a video of that and when it does the weird thing where it idles real low and dies.

[Liamk182]

Hey, looking at an old post, one user, who describe a similar idling issue, replaced his gas cap and stated that that seemed to clear up his issue. Have ordered one for myself so will let you know.

[steve520]

That would be hilarious if it was the gas cap. It seems like it holds pressure very well I hear the woosh of pressure come out when I open it thanks and let me know.

[steve520]

https://youtu.be/uk3efNCJGns Theres a video of a cold start and a hot start didn't get the symptoms to happen where it dies on the hot start but i explained what happens sometimes.

[87rustbucket]

I would check the throttle and maybe clean it out to make sure its not sticking.

[steve520]

I cleaned it out and lubed up the valve that opens and closes. Seems like it moves well so I don't think that is the problem. Thanks though.

[87rustbucket]

Sorry, I missed that you already checked that.

[Liamk182]

Gas cap didn't help...sorry for the false hope! Anybody know if a hot air pipe with a hole in it would affect the idle? It's getting harder and harder to stop and not stall the car!

[steve520]

https://youtu.be/jDedap3alHY Got a video of where it has a weird start-up this is what happened after it was heated and left for around 30-45 minutes. I turned the lights on so you could see the dash in the video and it happened. Almost wondering if that was because of an electrical load and maybe it happened before when I had the A/C on i'll monitor. Too bad on the gas cap. I would try the suggestions with cleaning the throttle body making sure thats all good.

[Dr_Snooz]

Have you tried cleaning the IACV yet?

[steve520]

Actually replaced it with another used one I bought from the website. Mine was originally throwing the ECU code for it and figured I needed a replacement. Put the new one in and the ECU code went away. I'm gonna try to replace it with another IACV and see if it helps.

[Hauntd ca3]

just looks like the trans selecting 1st to me.
Does the atf smell burnt even though its new ?
When the clutches in the trans in these things start to give up, the shifting goes all to hell.
They will hold gears to long, not shift down properly , shift quite firmly , as in firmer than normal .

[steve520]

Smelled the tranny fluid it smelled normal. But i have had the experience where it holds too long though in gear. When the shift hits thought it isn't hard its fairly smooth actually. Will adjust tv cable tomorrow. Also will put another IACV in tomorrow not throwing any codes just want to see if it makes a difference. Thankfully AZMike sent me two of them for one.

[Liamk182]

I'm slowly narrowing mine down and being a manual I'm thinking it might be the dashpot. Is yours manual?

[steve520]

Wish I could say the same for mine as well but it's an automatic. You are probably better off you have a manual though. Because if my automatic transmission is going then ugh thats not a good day.