98 Civic EX 2 door: CEL with codes P0700 & P0715 - and D4 light blinking

Howdy Automobile Experts,

My wife’s(who is in school out of state) 1998 Civic EX 2 door coupe with 127.7k miles has been showing the Check Engine light for a week now - had her get it checked at a local Meineke and the codes are P0700 and P0715 - also the D4 light is constantly flashing while she drives. There is no discernible issues/change in the driving experience except she says the engine sounds louder and sometimes it accelerates slowly. Next, took the car to a local tranmission shop and got an estimate of $432 for electrical diagnosis test $120 + a transmission fluid flush(73.50+54) and if required $151 for input turbine speed sensor.
I believe Honda has a TSB on this (01-012). I saw a member on a honda civic forum was able to get this resolved under an extended emission warranty( http://www.hondacivicforum.com/forum/mechanical-problems-technical-chat-8/obdii-p0715-65842/ ) - so I called Honda customer care but they said the TSB does not apply to my 1998 Civic. Is there something I am missing in reference to coverage from Honda for this problem - I see that the gentleman who was successful in getting this done from the dealer under an extended emissions warranty had a 96 Civic and someone mentioned 96-98 model years in the discussion on this issue.
We have a baby on the way so will be buying a bigger car before the end of March - intend to keep this car as a secondary for occasional use (if the cost to fix this issue is not in the thousands) - so I am trying to figure out what makes the most sense :

  1. Should we bring the car to a local dealer ? this one dealer said they will diagnose for $139 and if I get the work done there - the testing cost will go towards repairs.
  2. Drive the car as is - and try to find a local mechanic when I’m there next month.
  3. Get a transmission drain and fill - believe a trans flush is not usually recommended(http://www.letsrun.com/forum/flat_read.php?thread=3059771)

What would be the minimum amount of work(money) I can get done to fix this ?

Please advise on the pros and cons(risks) of each option and what makes the most sense.

All input is highly appreciated.

The P0700 is just a general code that says something is wrong with the transmission. It does not point to a fault.

The P0715 points to a faulty mainshaft speed sensor. The sensor itself may not be bad, it could simply have come disconnected somehow or the wiring has become chaffed or broken. This usually leads to hard shifts. It can also indicate a mechanical problem inside the transmission. although it is not in the book, I would suspect that it would cause the speedometer needle to hunt around a little, but I’m not sure about that.

a P0715 is not listed as one of the faults that causes the D4 to blink. The D4 is the “check transmission light” version of the check engine light. To pull the code for the transmission, you need to either go to the Honda dealer for the diagnostics or You can pull the codes yourself by shorting the P2 connector.

The P2 connector is located on the passenger side at the top of the kick panel just behind the glove box. It is a 2 pin connector that just hangs there with a cover over it. remove the cover and short the two pins, turn the ignition key to the on position (do not start the motor) and the D4 light will blink a code, either a series of short blinks for codes 1-9 or long and short codes for codes 10 and up. A long blink is equal to ten short blinks. I.e. 1 long and 5 shorts would be 15 for the P0715 code. If any other codes show up, such as 1, 2, 5, or 6-9, that would help point to a more definitive failure.

If the transmission is working smoothly and not giving you any problems, then try this, open the hood and find the underhood fuse box. Find a fuse labeled “radio”. This fuse is actually the keep alive voltage for the radios memory, but it is also the keep alive for the PCM and the transmission. Pull the fuse for 10 seconds. You will loose all your radio presets along with the code if you have the anti-theft radio. If your radio has a blinking red LED on it when the engine is off, be sure you know the anti-theft code before doing this.

If the D4 starts blinking again, then you might be better off having the Honda dealer do a full diagnostics. It is quite a bit of work so the charge is justified, its not just hooking up a code reader. But at least you will know exactly what is wrong, no guessing.

“she says the engine sounds louder and sometimes it accelerates slowly”

For the most part I agree with Keith, except that I noticed the above comment which suggests that there really are operating symptoms in addition to the other indications of a tranny problem.
I’d let the dealer do the diagnostic before making any decisions. It needs to be done.

Many thanks, Keith and The Same Mountainbike. Will bring it to the dealer.

One last question, gentlemen. How risky is it to drive the car like this like 45 miles a day till next week Monday or Tuesday night - and drop off to dealer then ? Could the delay prove to be expensive?

I don’t think so. It sounds like the tranny isn’t shifting, but not slipping either.
But I’m not a tranny guy. If you have any doubts, have it towed. A tow might seem expensive, but it might save you a lot more than it costs.

Thanks a lot!

Take it out for a test drive. Let her drive while you watch the tachometer. As she accelerates normally to 50 mph after the vehicle warms up, you should see four distinct drops in the tach as the speed increases, one for each gear change and one for the torque converter lock up.

The tach should read around 2000 rpm or slightly higher at 50 mph. If it passes this test drive, then it should be OK to drive. If it does three drops and the tach is around 23-2500 rpm at 50 mph, then the lockup torque converter is not working but you can drive it safely.

If the problem is more serious, such as slipping, then you will need a new or remanufactured transmission. It won’t matter if you tear it up a little more, it will cost the same regardless, but there is the risk that it could go out completely and leave her stranded somewhere. If you can handle the risk, then go ahead and drive. Just stay off railroad tracks.

Gentlemen, something else came up. Appreciate your input,Keith except I’m out of town for a bit so couldn’t do the test drive. Had my mind made up to bring car to this Honda dealer for a diagnostic - since they had said the testing fee would go towards recommended repairs if I decide to get them done - else I pay $139. So I called for an appointment and spoke to this service advisor - who asked what the problems was and told me right away that even though Honda has a tsb(http://www.justanswer.com/uploads/HondaJosh/2009-04-18_023457_zzz.pdf) on this issue, in his 10+ years at that dealership, the repair has always required replacing the transmission - between $2000 and $5000. Then I wasn’t sure what to do specially since my Firestone guy checked the records on my car and told me I had a transmission fluid drain and fill done April, 2012 - and car has gone less than 20,000 miles since. So, I thought I’ll use a $30 off $50 coupon and bring car to Firestone for a diagnostic and see what they say. That was supposd to happen mid week. However, the car broke down today. My wife was pulling into our driveway when it started letting out these strong fumes and there was all this some from UBS the hood and she then noticed a green liquid coming out from the grill on the front. I had her take the at to the Firestone but it got really heated up - went all the way from C to beyond H in like less than a minute at the end of her trip. The car is sitting at the shop and they said they will check for $40 and let me know what’s wrong tomorrow. Thoughts on what might have occurred,gurus ? Is this possibly related to the transmission problem? Not sure at all I want to invest 2-5 thousand dollars on a 98 civic ex with 128k miles - worth no more than 5 k. Many thanks for your advice.

The green liquid is coolant, that’s why your engine got hot so quickly. If she drove the car like that for too long, you’re looking at a new engine to go with a new tranny.
As it sits, if there’s engine damage, and your current trans problem, your car is NOT worth $5k, it’s worth scrap metal value. Hate to say it, but you’re gonna be needing a new car before the end of March

I’m afraid that now you will need an engine and a transmission. When you first mentioned Firestone, the first thing that went through my mind is wrong transmission fluid. Some of the issues you had were indicative of just needing a shift solenoid, which would not have been that expensive to replace, but it might have needed a reman transmission.

Over heating a Honda engine almost always means a blown head gasket. At the low end, head gasket $1000-1500, radiator hoses or radiator $500, transmission shift valve $250. At the high end, radiator and hoses $500, engine $6000, transmission $5000. Do you feel lucky?