linear shift solenoid goes bad too often

I had this problem with my 1996 civic before. With an warm engine,
shifting from 2 to 3 causes the engine to rev very high for fraction
of a second. I took it to a Honda dealer and they said "Transmission
has a flare". They asked me to replace the transmission.

Then I took it to Aamco and they said linear shift solenoid need to be
replaced. It was replaced and the problem recurred in 3 months. I
asked them to go for Honda parts this time. They did that (as they
said). Again after 1 year the same problem.

It has 228K km, coolant level is okay, Transmission fluid is OK
(changed a year ago and its pink), regularly changing oils from Honda
dealership.

I know it will cost me another 400 dollars to replace the solenoid.
Any idea why its going bad so frequently? Thanks.

 

Perhaps the first replacement solenoid was not new. It may have been on its
last legs.

There could also be a problem in the transmission control conputer. Solenoids
need a surge of current when first turned on to pull it in and then considerably
less to remain activated. Maybe the control unit is not reducing the current
flow through the solenoid after that first inrush thereby cooking it. That
might cause it to fail prematurely.

Have you checked the transmission computer for error signals? When the ignition
is on, a light-emitting diode may flash on the computer module. The number of
flashes, if any, indicates which problem the computer is experiencing. I don't
know where that is on a '96 Civic - probably under the carpet under the
passenger's feet.

 

i don't think it's just the solenoid. while they can and do go wrong,
if the motor's flaring, it's much more likely a problem with the general
condition of the motor.

my experience is that basically, the transmission expects the motor to
produce a certain amount of power in a certain amount of time in the
event of a downshift. if it's too sluggish, the clutches don't lock and
the motor flares. my 89 civic was chronic for this when i first got it.
and that's why the previous owner sold it - they'd been told it needed
a new transmission as some frightful expense.

so, i came in and sorted the motor out, adjusted the shift cable
properly, etc. and now the car's fine.

checklist includes making sure the cam belt is correctly tensioned,
ignition timing is correct, all the ignition components are in good
order, the valves are adjusted correctly, egr system is ok, transmission
fluid is ok, coolant levels good with thermostat working correctly, etc.
take care of all the little things that can affect general engine
health, i bet this problem disappears like mine did.

 

Hi Jim

In my case its downshifting okay but the problem is with upshifting
from 2 to 3. If I press on gas pedal a bit harder (than what I usually
do) the shifting has no problem. What I will do is to have these
responses printed and take them to my mechanic. I like to get this
things sorted. The car is otherwise fine.

By the way, what motor you are talking about? Is it related to the
engine or the transmission? (Sorry, I have no idea about auto
engines).

 

i would caution you on who you go to. you don't want to pay $400 for a
$110 part. and you want someone who knows more than "replace the
transmission".

i would recommend you take care of the general condition things with the
motor and see what effect that has first. change the fluid on the
transmission one more time too.

mine's the 89 with the d15 motor. it has a "kickdown" cable and lockup
clutch solenoid but no shift solenoids like yours. i did have a
solenoid go bad in a way that it would trigger code on one ecu, but not
another. i figured my old ecu was bad and replaced that for $35 at my
local junk yard. as a diagnostic tool, you can try that too. you can
always sell it again if it turns out to be unnecessary.

 

I should also mention that if you have the solenoid connectors apart, measure
the resistance of the solenoids to ground. They're usually less than a few
dozen ohms. If they show several hundred ohms, they're bad. That increased
resistance causes them to heat up more quickly. A hot solenoid core saturates
magnetically and won't release leading to the flaring.

 

alternatively, solenoids that run hot cook their flyback diodes and in
turn fry the ecu. after a while anyway.

 

I took it to my mechanic and he took it for a test drive, opened hood
and inspected something while somebody started the engine (put it in
drive and also at reverse). After that, he said "if you wanna believe
me, your transmission and everything is fine". He also asked me not to
pay too much attention while driving.

May be he is right, may be he is wrong. I came back home. That's the
end for now.

I found a forum post at http://www.fordforums.com/showthread.php?t=112967.
This is exactly the same problem as I was/am facing:

=========starts====================
transmission flare when shifting

Have a 96, 4.0 ohv, 114000 miles on it. Transmission flares when
shifting from 2nd to 3rd under light load. This does not happen all
the
time, but enough to have me worried. Seems to happen only when trans
is
at operating temp, never when cold. Have read up on this problem, some
say a bad gasket on the valve body or loose valve body bolts will
cause
this. I have a B&M Shift-Plus electronic shift kit that is supposed to
tighten up the shift. Would it help to install it? I don't hot rod,
just
want max life out of the truck.
Thanks,
Jack
==========ends===================

 

see how it goes.

different type of transmission - has planetary gears and clutch bands.
adjusting the bands usually fixes that.

 

Did he experience the flare problem or did it not appear for him?

If there really is a problem, it will get worse. Perhaps the problem will even
be exhibited when the system is cold.

By the way, you can have someone check the resistance of the solenoids even when
the transmission is cold. Bad ones will still show a very high reading on an
ohmmeter.

 

It seems that he did not feel the flare problem. It only occurs when
pressing the gas "unusually" low.

It does not show when cold. Cold transmission shifts good.

I've adjusted my foot and now the problem seems to be disappearing.

 

did you get the motor maintained so it's operating as well as it can?