I have an 04 Honda Accord 4 cyl w/ 80,000 miles on it. The shifter will not go out of park without manually pressing and holding down release button near shifter. It also does not shift smoothly. The RPMs will go up and as soon as I let off the gas they suddenly drop. Also, the drivers side window sometimes does not go down unless I press the button a bunch of times. The headlight will dim ever so slightly off and on while I'm driving it as well. The engine light and the engine maintenace lights are on.

I have had the TPS sensor replaced as well as the map sensor.

I recently brought it to Aamco and they said that it was reading a tps sensor code and a baro sensor code. Unsure of the exact TPS code it was reading but the baro code was p2227.

The air filter is clean and there is no blockage.

They told me that the first TPS sensor I had put in was installed wrong and was fried. And that I need a new throttle body kit. They also said that if that did not fix the problem then I would need a whole new ECM.

I was also told by a mechanic friend that it could be a shorted wire somewhere and that replacing the TPS body and ECM may not even fix the problem.

Also, I have heard different opinions on the location of the Baro sensor. Some say it is part of the ECM and then I have heard that it is no where near the ECM.

I am considering ordering the TPS body kit and the ECM online and having a co worker install them because I know nothing about doing anything to cars.

Do I have to have the ECM programed by a Honda dealer for it to be able to run if I have a new one put in?

Also, I feel as though this car may just be a money pit because I keep getting the run around with car technicians. I don't know if it's worth trying to repair or if I should just trade it in while it stills drives.

 

if in fact the tps was installed wrong and is no bad, that needs to be addressed first, the baro sensor code could be related, but be prepared for it not to be. it DOES live inside the ECM and part of the procedure is to update the software in the ECM if it has not been done, if this doesn't fix it, you'll need a new computer which will have to be flashed for the the security/antitheft systems by the dealer with the HDS factory system.

even if you were to trade it in, you'll get ALOT less with the check engine light on.

 

The diagnostic for P2227 has different instructions depending on what other codes are stored. You need to find out all stored codes and post them for someone to help.

This is a complex fault, however odds are a bad ECM or BARO sensor on the ECM is the problem. Replacement (new or used) will require support form Honda to get the car to start. This could indeed be a money pit, but may be cheaper to repair than sell at deep discount.

Used ECM available via car-part.com for <$100.

good luck

 

So far, symptoms point to faulty Throttle Position Sensor (TPS) or wiring. You most likely got the trouble codes P0122 (TPS) and P2227 (Baro). Get the code(s) again to confirm.

The ”Can’t shift out of Park” issue may be related to the Throttle Position Sensor (TPS) problem. As long as it is not a brake light switch issue, then there may be a problem with the TPS. If the TPS reads/thinks it is off idle, the ECM will not send a ground signal to the interlock switch, to let it come out of Park.

See these links which are similarly related problems:
Honda Accord: there is an check engine lighjt on - JustAnswer

03 Accord 2.4 cpe, shift interlock solenoid not working - Honda-Tech

This Honda technical service bulletin is for the CR-V. Although I am not sure; but, I believe there may have been something similar for the Accord.
http://www.crvownersclub.com/TSBs/2005/04-008.pdf

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First reset the ECM (car’s computer) and perform the idle learn procedure, to see if this may get resolved by yourself.


The following is generally the Idle Learn Procedure:

Make sure all electrical items (A/C, audio, lights, etc.) are off. Disconnect battery for a short while (3 minutes would be fine). Turn ignition switch to ON (II) and wait 2 seconds. Start engine and hold engine speed at 3,000 rpm without load (A/T in P or N, M/T in neutral) until radiator fan comes on, or until engine coolant temp. reached 194 degrees F. Let the engine idle for about 5 minutes with the throttle fully closed. (If radiator fan comes on, do not include the running time in the 5 minutes.)

 

However, I have to agree with Dr. D and TexasHonda, there may be an ECM problem. Sometimes shorts from sensor wiring have been known to damage the ECM.

 

You probably replaced the original TPS with an aftermarket like from Blox or Omni; as Honda didn't sell the TSP separately, only as part of the throttle body.

Here some more info.

Check for debris holding the throttle valve open or a tight throttle cable. (There should be 3/8 to 1/2 inch [10 to 12 mm] of free play in the throttle cable.)

Check for poor connections or loose terminals at the TP sensor and the ECM/PCM.

Update the ECM/PCM if it does not have the latest software.

I've attached some info. regard the P2227 trouble code at possibly related to the TPS.

 

Thank you for replying. I'm going to replace the throttle body assy. and then go from there. I'm am having trouble finding the throttle body assy w/ the sensor. Most of the ones sold on Ebay are just the body & sensor seperatly. Where can I find the whole assembly?

 

Also, is the sensor welded to the body? I'm trying to figure out how the mechanic that I had replaced the tps replace it if its welded to the body.

 

For new, Honda sells the throttle with TPS attached. Internet Honda dealers like Bernardi Honda Parts, Majestic Honda, Honda Parts Now sell it for around $251 plus shipping. I believe it is Honda part number: 16400-RAA-A63; but, double-check based on your car's VIN.

The TPS is not welded on the throttle body. They are a type of shear bolt; the screw/bolt originally had a different head on top that breaks (shears) off upon tightening, leaving the tamper resistant head. (See picture.)

To get off the shear bolt, the mechanic may have cut a slot on the top of the head and used a flat-tip screwdriver to turn it out; or use a center punch and hammer to rotate it out. (See picture for center punch and hammer method).

For the TPS, Blox and Omni are aftermarket sellers of the TPS alone.

Option is getting a used throttle body and adding a new aftermarket TPS. Blox TPS retails for around $100, Amazon shows it for $80.

Depending on how much the used throttle body w/out TPS might be, and having to purchase another new TPS, you may be better off ordering a whole new throttle body (which comes with a new TPS) from an internet Honda dealer.

 

What is the reason that I would need a throttle body? Technically I would just need the sensor right? Is there a point to buy the body & sensor seperately and then put them together? I'm thinking that the mech. that put the tps on last time may not have adjusted the sensor properly. I'm going to check to see if I can have the sensor re-adjusted to the proper output & see if that fixes it. Or if the sensor is bad just buy a new sensor. The auto place I brought it to last time said the sensor reading was not what it was supposed to be. I'm assuming they wont adjust it and thats why they said I needed a throttle body assy b/c they cannot get just the sensor.