Questions: ECM conn, cabin filter, and more [1997 Y33]

[miata007]

Hi all,Working on check engine light issue over the weekend after OBDII purchased from Walmart ($100).

Have few questions here:

1. According to FSM, need to have access to the ECM connector. I've took out the glove box and found the ECM. Problem was I couldn't remove the ECM harness protector. The was only 1 bolt which I've loosed but there was a metal/frame/bracket on one end that kept the protector from coming off. Addition item/brackets need to be remove in order to get access?

2. While the glove compartment is out, I've decided to finally replace the cabin filter. Couple problems here. Does the car comes with 1? (yr 1997) If yes, can someone provide more details on on how to get to it?

I've did a search on cabin filter and found many response from (maxnix) saying this topic has been discussed before but couldn't find the details instructions. It is not in my FSM perhaps I have an older version.

3. Back to the DTC code, the scanner gave me 3 codes all complaining about the throttle position sensors. P1020 TPS P1705 TPS AT P????? can't recall the code now but it mentioned: TPS and Tandem.

Anyway, according to FSM again, it recommend me to start out with P1020. I've skipped the ECM voltage measurement part as I couldn't get access to it. I proceed to the next part and start measuring resistance of the TPS (EC120). Here are the results (engined warmed up):

Conditions Expected MeasuredThrottle (ohm) (ohm)-------------- ---------------- -----------------closed .6K .6K open 5K 3.33K

3.33K vs 5K(expected), it is off quite a bit. As a result, FSM suggests to replace the TPS. I've decided to order the part from Joe despite the fact that I have skipped the ECM testing part. Any one has replace this sensor before? I appreciate any tips in working with this issue/code.

4. One last question. In FSM, for each connectors they mention T.S. and H.S. I believe they stand for terminal side and harness side. Can someone please confirm and explain. I got confused following the FSM.

Thanks for reading and all the help!!!

007

[NightRiderQ45]

Search for cabin filter under member loystock. That's where I printed my info from but I haven't change mine either. From what I remember, there are two filters.

[maxnix]

I hear the 1997 FSM is incomplete on this site. Look at a later FSM. Very simple.

Filters (2) are one part number.

Don't dislodge ECU unless you have to. Use OBD II reader.

[miata007]

I don't have access to later version of FSM. Can someone help and post the later version here?

Thanks007

[maxnix]

http://www.nicoclub.com/FSM/Q45/

Be careful with the clips on the passenger modesty panel.

[bullittandy]

I think you've made a safe bet replacing the TP sensor without checking ECM connection.

Re: the cabin filter-look under the glove box and remove the big pastic cover with the courtesy light in it (I think glove box door has to come off as well?) and you'll see the two filters, they will prbably have grey plastic ends and there will be two of them, remove clip holding them in and replace with new. Prepare to be disgusted if they haven't been changed in a while!

[miata007]

TPS updates:Received the TPS sensor on Friday last week and replaced it. I first measured the resistance of the new TPS and able to show it is different than the old one. That confirms the TPS needs replacement. It only took 10minutes to replace and that because I try to be extrat cautious and not break other things in the process.

Drove the car for couple days (75miles). No problem so far. I wished I have got the OBDII scanner sooner. Best money I have spent on tools so far.

Cabin filter:Thanks Andy! I've found the filters and replaced both of them. What I am surprise is it is not as dirty as I would have thought after 4 years. It is about as bad as the old filter in my G35 which I replace every 15K miles.

Thanks everyone for you help and pointers!

007

[maxnix]

Don't know where you are located (please complete your profile!) but both my intake and cabin filter need replacement annually.