TDC sensor questions
 

I have been searching for days now and find contradicting info everywhere. I have 97 Accord LX Automatic. I checked the code and am getting code 8 for top dead center position sensor. I am trying to find out where the sensor is, is it in the dizzy or by the crank? If its on the crank do I need to remove the crank pulley to get to it. Going to do a timing belt / water pump change soon so would be nice if its right there to replace at the same time.
Would this be the reason for bad gas mileage? would it also be the cause of low power, or just the fact I am driving and automatic accord :) ?
Please only reply if you know or have experience with this...to much bad info out there already

Re: TDC sensor questions
 

If this is a 4 cylinder the TDC sensor is located in the distributor.

Re: TDC sensor questions
 

On the OBD2 96-97 F22B1 & B2 4 cylinder engine. The TDC & CKP are both found mounted on the oil pump housing behind the crank pulley. It will require the crank pulley and timing belt cover to be removed. If your planning on doing the timing belt and various maintenance it would be perfect time to replace them. I say them becuase the TDC & CKP come as a complete harness. Part number 37840-P0A-A01

http://i133.photobucket.com/albums/q...CKP-Sensor.jpg

These sensors don't go bad all that often though. It is usually a faulty, dirty connector or a wiring issue. Test/Check those before you go replacing stuff.

Oh and if it's a V6 it's part number 37500-P0G-A01 and it is also found mounted to the oil pump housing behind the crank pulley. ;)

Re: TDC sensor questions
 

Doh! My brain farted. :)

Re: TDC sensor questions
 

lol :beer:

Re: TDC sensor questions
 

Just curious:

Do you have access to an actual OBD2 scan tool to get the most accurate code description? I've never been a big fan of using the flashing codes for OBD2 cars.

I've never seen the CKP sensor pictured above there go bad on any 96-97 Accords in the 10 years I've worked at a Honda/Acura only repair shop. I've seen plenty of the 98-02 year model Accords have the CKP/TDC sensors go bad for whatever reason, but again not so much the 96-97.

Re: TDC sensor questions
 

i just had that same problem with my car after i rebuilt it, P1361 TDC sensor intermittent interruption, so i just reran the wires with 18/4 shielded and that fixed the problem, i reran them from the two sensors by the crank gear up along the motor under the intake and where they came out on the other side i finished the splice,and with the shield wire the end by the crank i put one with a ring term on the block and the other end i just put to chassis ground, thought it would be alot better then buying new a sensor, fyi my motor is f22b1 2.2 vtec

Re: TDC sensor questions
 

Thanks for the replies. I will go and get the car scanned at a shop and hopefully get this done. I dont have the time right now to do the timing belt change and my jack broke so I have to pay someone to do the tbelt unfortunately.

Re: TDC sensor questions
 

Good Info. The pic isnt clear...how many tooth on the TDC sensor, and how many revolutions per one crank revolution?

Re: TDC sensor questions
 

There are 720° in a complete cycle of our Honda engines. Therefore if the trigger wheel for the TDC sensor on the crank has 2 teeth. It will then have 4 pulse signals for a complete cycle.

I posted this in another thread....I'm pretty sure you responded in it!.... ;) :beer:

Re: TDC sensor questions
 

[QUOTE=i got honda prelude 5gen and engine H22a2 and i wanna just to involve in this reply and ask something,i got problem of long cranking and sometime car crank but not turn on,than i turn key back and start him again and he turn right away from first spark,that is one and othe question because i see this picture,and r they same for prelude 93y engine 4th gen and for 97-01y gen?? thnx in advance if you can help in any way

Re: TDC sensor questions
 

r this tdc sensors same for prelude 4th gen and 5th gen,because i look on ebay and shape of these r same and nr of conectors r same...i got loing crankings and sometime car even wont start up,sometime in driving around 3000rpm s car wanna to jump of the street...thnx in advance

Re: TDC sensor questions
 

If you have a code reader or can find the two wire blue connector, see if any codes are stored in the PCM.
Check for air, fuel and spark next time you have a hard time starting.

Re: TDC sensor questions
 

ALL checked,i clean IAC,EGR valve,check for codes,but nothing(except sometime in driving egr turn on from it self,but nothing else....now for last two weeks car sometime die in driving when i press clutch....and other two times got code for Top dead center sensor,and that is when car get wild on 3000rpm....so i look for sensors on ebay and find for 20-30$ so what i wanna to know,is it same thing for 4gen honda prelude and 5th gen prelude,H22a2 and H22,because they write stuff for honda from 90 to 2001year all compatible,or take out part and check with nr on him,but for that i need to take down timing belt and shitload other things,so car work still,when is long caranking and no start ,just turn key off and start him again and problem solved for now...money money money...thnx on replys

Re: TDC sensor questions
 

There may be a difference from OBDI and OBDII cars. Here in the US that change happened in 1996, which was still the 4th generation 'bullnose' Prelude.

If you have a wire harness, connected, going down to the front of the engine. Then you may have the OBDII crankshaft mounted sensors.

OBDII will have ~6 wires from the distributor, with crank mounted sensors.

OBDI will have ~10 wires from the distributor, without any crank mounted sensors.

Re: TDC sensor questions
 

i will check,for now mad mike thnx on BIG help..!!!! i am crazy already with this car,power steering pump leak,than swap made from 2.0i to 2.2l vtec,we leave same stuff inside,only naked engine put in,and fewfew years that was functional till last summer...all gasquets piss oil all around,than check engine turn on for egr,and than some squeky sound comming beneath timing belt,ignition switch also,than this top dead center sensor....so man thnx on help ,will check and return with some answers!!!

Re: TDC sensor questions
 

ok, i recently replaced these sensors on a 2002 accord EX auto 2.3. code was saying TDC/CKP sensors. so, got the sensors and 3 hrs later was done. car still not starting... replaced the dizzy twice, still not starting.... take dizzy back get another. car starts but cel is still on for TDC/CKP sensor and now the car will not rev over 3000 rpm's. if you ease into the throttle, it will run and drive fine but gas it up off the go and it won't go over 3k.

when i replaced the sensors, i made sure it was TDC, made sure all the tick marks were lined up, i didn't take the timing belt off at all.

a couple weeks go by with me having it looked at by others finally i take it to honda to diagnose. they spend 3hrs on it going over everything and tell me that the ECM is bad. ok, I've heard of them going bad in that year so ok. i get one from a local yard for $100 and bring it back to honda to refresh new ECM to my keys. go to pick it up... still has the TDC/CKP cel and still won't start. if i put the original ECM back in, it starts but cel is still on and won't rev over 3k again.

I'm at wits end with the car and with paying for this and that. turning to honda-tech for help. I've googled everything under the sun to try and fix and i can't.

HELP

Re: TDC sensor questions
 

Have you checked the wire harness itself?
Verify that the sensors are clean and the sprocket on the crank is clean.
Locate the wires from the sensors at the PCM connector, and check the resistance. If you have an open, incorrect value, or intermittent connection, then the problem lies in the harness. Could be a sloppy pin, look for corrosion at the connections as well.

Re: TDC sensor questions
 

yea honda checked the harness from the sensors to grounds etc etc. problem here is, its my daughters car and she's about 6hrs away. her and her mom are handling this and relaying info to me as it happens. so I'm sure things are being lost in translation along the way lol

anyways heard from them last night. left it at honda for more diagnostics and are getting another ecm to try. going to be monday before i hear anything else

without taking the timing belt off, could there be anywhere the timing gets thrown off? that year accord has non-adjustable timing at the dizzy from what i found out so i don't know if thats the issue here or what.

Re: TDC sensor questions
 

Having same issue with my dads 2000 accord f23a I was suspecting the crank sensor or the ecu since I've replaced everything and check everything eles. Did you figure out what it was?

Re: TDC sensor questions
 

no not yet. haven't been able to work on it or look at it. car is located about 5hrs away from where i live and i just can't get there to look at it. honda says theres a wiring issue between the sensor and the ecu in the harness somewhere. i may go and pick it up and bring it closer to me and have my honda friends check it over.

keep me posted in case you figure out your dads car. i want to fix this so my daughter can get back to driving!

Re: TDC sensor questions
 

Ok thanks for the reply. It's wierd my dad spun a rod bearing in his f23a1 had 435xxx on it body was in good shape so I sourced out a Jdm f23a and swapped it in. everything went fine swapped everything over from his old engine onto the Jdm one except the crank sensor. And now it's retarding the timing to -10 deg when it's warm. Something's fishy. I'll let you know if I find anything out. Thanks for the reply cheers

Re: TDC sensor questions
 

did you guys ever find the fix? same issues, no solutions

Re: TDC sensor questions
 

Fix for what issues? The original question was about a code 8 and where is the TDC located on an OBD2 96-97 Accord. Answer is, it's mounted on the oil pump housing behind the crank pulley.

If you have a more specific question please ask.