h00rj

I just bought this '88 Civic DX hatchback and it's having troubles staying in overdrive (or 4th gear, not sure if it's technically "overdrive")

I've noticed it drops out of 4th on the highway whenever I lay off the pedal, say while going downhill.
Then, when I press the gas again it goes back into 4th.
I can make it happen reliably, but it drops into 3rd every time I go downhill, or draft a semi.

I mean, there is a point in the pedal range where it pops out of 4th. Not necessarily just letting off the gas, just not very much pressure.

It kicks down from 4th to 3rd and so-on when flooring it like it's supposed to...

I've adjusted the throttle -> transmission cable as per the manual, when I first bought it it was doing this, and I found the cable to be loose, but tightening it didn't help... I've even over-tightened it. It just made it shift harder, but it still dropped out of 4th while trying to hold a constant speed.

Anyone have any ideas?

Oh, no check engine light, by the way.
Thanks lots!

h00rj

I've read somewhere about it possibly being the temp sensor? Saying it could be the ECU trying to rev up the engine to lower the temp... Temp gauge has never gone above half. Not sure if that's it...

Also, could a vacuum leak be doing this? I don't think I have a leak, because otherwise the car runs and idles perfectly... Just an idea to throw out...

I've noticed my speedo is about 3-5mph fast. Wrong tire size, perhaps? It came with steel rims, I dunno what the stock is though... I'm getting some stock 15" 2000 honda aluminum rims tonight, I'll see if that changes anything.


Anyway, I know I should do a trans swap, but my wife drives it and she's (for some reason) terrified of manual transmissions... Hell, she freaked when I told her it has manual steering. Besides, the auto accelerates and drives fine, just not as good as it could.

Any further ideas? I'm prettymuch lost and google isn't helping.

h00rj

I got the new wheels. The speedo is right on now, but still no change on the overdrive issue...

I read somewhere else that loose transmission mounts can cause strange transmission problems. How can I tell if they're loose, or looser than they need to be?

RAM_Designs

I had the same issue with my '88 hatch and have the same thing with my '87 hatch. Both cars had around 100k miles, not sure what the issue is. Any help would be much appreciated.

99teggsr

Remove and clean out the lockup control solenoid, change trans fluid. My auto CRX used to drop out of overdrive at all kinds of random times but after cleaning the lockup control, making sure TB>kickdown lever was tight, and repairing all vacuum leaks it rarely did it.

It still would drop in an out of overdrive every now and then and I was starting to think my TPS may need calibration as it seemed to always happen at a certain amount of throttle input.

Run HONDA OEM ATF. Nothing else ! Running clean Honda ATF made my tranny shift sooo nice. You must drain and fill it about three times over the course of a month or two to really get all the gunk out if you have alot of miles.

RAM_Designs

Thanks for the info. It's hard finding info on these '87's, do you have a good link to so e literature on all the stuff I need to know for this problem or these cars in general?

RAM_Designs

It shifts fine it seems, it just doesn't stay in overdrive at all unless I push the pedal down to accelerate, then it'll drop down. And once I coast again it pops out. Also, I can floor it when I'm in 3rd but it won't downshift to 2nd, think I might have a tps issue also, but I'm no mechanic.

RAM_Designs

I just bought an owner's manual and the 1984-1991 civic shop manual. I don't know what the hell I'm doing with these cars so it should help me easily find and identify things.

4drEF

Sounds like you are letting your foot off the pedal when it jumps out of 4th/OD?
If that's what you are doing then of course it is going to drop out of OD. Autos don't have an actual 4th. It has 3 gears and a locking torque converter. It thinks you want to decelerate because you lifted your foot enough for it assume that its time to start slowing down.

Try not tailgating semi's - or as you call it 'drafting' and keep your foot on the pedal to maintain speed. If you want to cruise downhill with your foot off the pedal the get a manual transmission.

RAM_Designs

This happens with normal highway driving, maintaining a given speed, it's not from just going downhill or anything like that. I have to push the pedal about half way down to get it to go into overdrive, causing me to steadily accelerate at the same time, so I have to let off the gas to get back to a steady speed. And at that steady speed it will not be in overdrive.

F22Master

Im pretty sure its normal. Mine does the same thing. It also will kick out of OD at anything above 3k rpm (~70mph on the speedo) on the highway.

Also, it's 4 speeds + OD, not 3 + OD.

RAM_Designs

I guess it just doesn't make sense, why even have OD if its not going to be used? It definitely doesn't feel normal...push down on the pedal and shift down into overdrive, cruise at normal speed and no overdrive.

h00rj

Wow, I forgot about this post. Thanks for all the replies! I'm still having the problem, however. Just kinda live with it now.

4drEF, I'm not letting entirely off the gas. I could understand it downshifting when I let off the gas completely, but it jumps down when I let off just a little bit.

Basically, on a level surface, while I'm accelerating it shifts normally and stays in the final gear. While trying to maintain a constant speed, with constant pedal pressure, it kinda bounces back and forth between 3rd and 4th. Tell me this isn't normal...

I'll give what 99teggsr says a try and report back! I'm kinda wondering about the TPS also... How does one calibrate that thing?


Side note, I wonder if we could just wire up an "OD" switch... Flip the switch and it locks the transmission up to OD. Of course, you'd want to flip it back for acceleration. Possible? Impossible?

RAM_Designs

Can anyone tell me where the lockup control solenoid is on a d15a2 (I know, not really your guys' forte)? I can't seem to find any definitive diagram on it, and I'm still waiting on my shop manual to come in the mail.

I did a tranny drain, it was a bit too full (about half of the cross-hatched area ABOVE the cross-hatched area). I drained out about 2.5-2.75qts and put in 2, and I was right in the middle of the cross-hatched area. The fluid was really clean though, like they just did it before I bought the car.

But I now have a Weber K726 coming my way, and I'm doing the full devac since a lot of my little vac lines have little cracks at the ends or just flat out don't fit very snug at all. Hopefully after all of this there will be SOME kind of difference.

But the main thing I'm worried about now is removing and cleaning the lockup control solenoid on my '87, so can anyone help me with that? A pic would be great. I've registered at rpr.com but can't post or start a thread yet, so getting exact answers is a little tricky.