1996 Civic - First signs of transmission slip?

Hello,

I have a 1996 Civic with 77,000 miles and automatic transmission.
Generally, it's in very good condition although lately i've noticed a
very specific condition which is my cause for concern.

The specific condition is when the car is at roughly 35mph, 3rd gear
with light engine load (i.e. a gentle hill) which demands a specific
throttle setting to hold speed. This causes the engine RPM to oscillate
between 1900 and 2100 with a period of 1 second. I can both hear the
note of the engine changing and see it happening on the gauge. Simply
changing the accelerator position stops the problem.

Is the transmission starting to slip? Is this the start of a big
problem or just a little niggle? I tried replacing the transmission
fluid recently with Dexron III (it was due for a change). Gear changes
are slightly smoother but it didn't fix this issue.

Any comments would be much appreciated! Thanks,
Jez

 

your ecu checks sensors on the input & output shafts of the gearbox. if
there's slippage, it immediately stores a code. suggest you get it
scanned - if there's a problem, it will show.

if you've changed the transmission fluid, make sure you use the special
honda-only atf.

 

==============================

You need to get that Dexron OUT of your Honda. Use only Honda Z1. Let it
drain a long time, fill with Z1, and drive a week. Repeat the process.
Dexron is missing some special friction modifiers your Honda can't
survive without. You will wreck it if you drive too long with it in
there. Same for Amsoil.

'Curly'

 

I filled it with Dexron III on the advice of my Haynes manual which
states "Honda ATF, Dexron II or III". I have drained it and filled with
Honda ATF-Z1 this afternoon as a precaution. Is it really necessary to
drain again in a week and refill? It's not cheap that stuff :-/

Jez

 

I've checked the Honda owners manual which also states "Use Honda ATF or
equivalent Dexron II ATF only". Considering I've been told that Dexron
III is designed to be a replacement for II, perhaps you could explain
what's going on.. Why is Dexron recommended in two different documents
if it wrecks the transmission? Seems a bit strange to me...

Jez

 

the honda manual says you can use dexron as a stop-gap, not for full
service. once you get that stuff out of your system and your shifting
gets back to normal, you'll see what we mean.

regarding your other post on the need to drain & refill again, the
reason is that you can't drain the wole transmission - you only get 2.5
quarts out on drain [because of all the fluid retained in the
converter], but you need 5.7 quarts on assembly from new. therefore you
only change 44% each time. you can see that it takes a few changes to
get that stuff out of there, and you need to do it each time after an
interval to make sure stuff is circulating out of the converter.

 

I called the Honda shop where i live after changing my front axles.They told
me(shop technician)to fill it with 10w30.I did ask for the special honda oil
but they told me that it will just do the same...Where do they get training
to say such things?

 

-------------------------------

For those who are confused, do not put 10-W30 in your Automatic tranny.
It can be used in a Honda Manual tranny, at least temporarily.

I think there are (at least) two different conversations happening :-(

'Curly'

 

Okay I see what you mean. I'll drain again in a week and refill. Thanks
for the assistance.

 

I've done a second drain today after a week of driving. Gear shifting
wasn't my concern although admittedly it is slightly smoother now. I'll
have to drive more to find out if the problem I mentioned before has
been solved.

 

------------------------------

The problem with the RPM sounds just like a TPS problem, but it's
unusual for your vehicle to have it at such a low mileage. Do you live
on flat land and use the Cruise control all the time?

Get hold of a multimeter with a needle (not digital) and unplug the TPS
(back side of the throttle) and set the Ohms scale to 10x or 100x, hook
up to any two of the TPS pins, and if the meter swings when you open the
throttle, you've got the common and one of the other two. SLOWLY open
the throttle and watch the needle. If it spikes offscale at the same
position as 1900-2100 rpm, you've found that your TPS is shot. Good luck
on an inexpensive fix. I used to have an e-mail address for a russian
guy who could get you one on the BLACK MARKET :-(

Use Google groups to search for tps. Some have found sources for the
potentiometer (only). It's really just a pot, like the one in your
volume control on your stereo.

'Curly'

 

Thanks Curly. I've had a look around on google groups and other people
have posted similar problems related to the TPS. I'll try the multimeter
test when I get a spare mo.

The car doesn't have a cruise control (unfortunately!). I do about 50%
highway driving however the previous owner may have had a different profile.

One question still lingers - why would the RPM vary though? The speed
(as far as I can remember) stays more or less constant. This is why I
was originally concerned about the transmission.

Jez

 

so, what code are you getting from the scanner? if there's a fault, it
/will/ be detected & stored!

 

============================

The quicker way to see if it's the TPS (and this works WAY better with
manual transmission). Put the car in first gear, and drive at the exact
RPM where you have trouble. This might be jogging speed in first gear.
If it's got a TPS problem, you might just see / feel it more clearly in
first gear. My Ford Aerostar rod like a bucking bronco when the TPS went
bad (manual tranny).

O.T. Have you ever used injector cleaner? You should, maybe a couple
times per year.

'Curly'

 

I've decided to get an expert to fix some rust next week so I'll ask
them to scan the ECU at the same time. I'll keep you posted

 

I checked the TPS today and it seems fine. There are no abnormal
variations in resistance. I put some STP injector cleaner into the tank
at the last fill. Time will tell if that solves the problem! Thanks
again Curly.

 

There are no codes reported. I've also checked my haynes manual and
there are no codes related to transmission slipping. How do I check
which transmission I have? The haynes manual lists:

S1LA - 4-speed auto with lock-up clutch
S4PA, S5MA - 4-speed auto with electronic control
S4XA - 4-speed auto with Transmission Control Module
AR4A - 4-speed auto controlled by Powertrain Control Module (PCM)

I'm suspecting it's only got the basic electronic one but not sure.

What else could be causing this? I've tried injector cleaner and I've
checked the TPS as described by Curly.

I appreciate this is a fairly specific problem which may be caused by
any number of things!