This morning I was taking my son to school. While stopped at a traffic light for just a second the car acted like it was going to stall but then started idling normal again. When the light changed the car acted like it just had a dead spot in the engine rpm's. Then the car would not shift out of 1st gear. Once I let up on the gas pedal a couple of times it shifted into 2nd but then would not shift into 3rd. While all of this was going on the car was still running like it had a dead spot while running. I turned around and went back to my house to get my other car. The symptoms did not change on the way back. Once I got back home I started the car to see if it had a flashing D4 light. It did not. While idling it had the same miss and the shifter will not come out of park. Can someone help me figure this out,I really love my honda. We have been through a lot together in the 16 years I have owned it. Thanks

 

I just jumped the 2 wire blue connector under the glove box and the check engine light blinks 4 long and 1 fast blinks whatever that code means. It also has a transmission code 15 which is the main shaft speed sensor. it has had the code 15 for over a year now but i have been ignoring it because the car ran great still. If this sensor finally failed completely will it cause the problems I am having? I was able to move the car out of park by inserting a key in the shift lock release.

 

Code 41 is for the O2 sensor, I think it is the heater circuit. If it is a ground issue this will affect other sensors in the system but may not trip a trouble code for them but they would cause the car to run like garbage.
Check your main battery lead connections are clean and tight.
Verify the main grounds at the transmission, engine mount and intake manifold are clean and tight.
Verify voltage at the battery, verify full charge.

Code 15 is for the shaft sensor, if it is fouled in gunk it will lose resolution and the TCU will not command a shift or the shift will be erratic. Check resistance of the sensor, check wiring to the sensor, pull sensor and verify it is clean/free of debris and slurry.

 

Thanks, I checked all the grounds and all are clean and tight. What is the shaft sensor close to so I can find it on my transmission and what is the best way to get to it? I guess the TCU is what has the shifter stuck in park. I am really hoping it is the shaft sensor and not the TCU itself.

 

Shaft sensors are located on the right side cover. Turn your steering wheel to full lock right and you should have enough room to loosen the bolts. Sensors are located at the 10 O'clock and 2 O'clock positions. If one is covered in slurry and gunk the other one is as well.

Don't think a 15 or 9 code would cause the shifter be locked out. Now if the brake pedal switch is sloppy it may not be giving full contact for the shifter interlock to power. Verify no fuses are blown either.

 

Finally got time today to look at the shaft sensors. I could not find the top one but pulled the lower one. It looked pretty clean but I sprayed it with MAF cleaner anyway and reinstalled it. The plug where the sensors plug into the main harness was soaked in oil from a small oil leak that I cannot seem to locate. I spayed simple green on the plug and all in the area of the plug and then hosed it off. After it dried I sprayed the plug with MAF cleaner and then took the car on a test drive. It shifts just like it should now and does not act like its going to stall out. I took it on about a 3 mile ride with a lot of starts and stops. I am hoping it will be ok now but I am not going to go to far away from home for awhile. Could the plug being soaked with oil have caused all this?

 

That speed sensor is a very important one, it tells the trans when to shift gears and if it cant detect that it goes into whats known as limpo mode where the trans wont shift beyond 2nd gear. I forgot to plug mine in when I did a drain and fill on my cars trans and I thought my trans was done. Found out I forgot to plug the damn thing in. You might want to get a new one, because that code doesnt come up for no reason. You may have only fixed it temporarily.