Getting 4 codes ... need experienced advice

[Mike_N_Austin]

Good news....I did fix the loping idle.

 

I cleaned and adjusted the "alignment" of the Throttle Position sensor. My car used to have a very eratic and loping idle.....would bounce between 500 and 1,000 RPM. It was very annoying.

 

Now the car pegs at 750 RPM and idles like new.

 

I removed the TPS and cleaned thoroughly with throttle body cleaner.

 

But when I first re-installed it back into the car and took for a test drive, the car ran very rough...almost like I was getting severe mis-fires and backfires. I then "advanced" the alignment of the TPS all the way to the other side.....and the car ran better....but would stay locked at high RPM. Specifically, if I put it in second gear and ran it up to 3,500 RPM and then I changed into 3rd gear, the RPM would stay pegged at 3,500, instead of quickly dropping during gear change. So I then reset the "alignment" of the TPS to center and it ran much better, and idled much better.

 

So I am not sure if it was the cleaning, or the realignment or both....that has fixed my idle problem. But...if you are having a loping idle...I definitely recommend cleaning and adjustment to the TPS. (Throttle Position Sensor)

 

The car ran better than I remember it ever running. I seem to have more power and acceleration.

 

I am hearing a lot of "knocks" and "pings" at high RPM....so I am hoping that the Knock sensor will improve the performance even further.....and allow me pass inspection

[Mike_N_Austin]

UPDATE

 

The Knock Sensor is in. Took it for a test drive and the "knocking" has definitely gone away at high RPM. So I am 99% confident that the original sensor was malfunctioning.

 

I disconnected the positive battery cable. Will let it sit 3-4 hours to reset the computer.

 

Please Please Please.....I hope the check engine light stays off

[Mike_N_Austin]

:mad:

 

AAARRRGGGGHHHH

 

Check Engine light came back on. Ran the codes at Autozone.

 

Now the MAP sensor is coming back faulty. No O2 or misfire codes...yet....so at least those may have fallen off. But...MAP sensor is a $ 200 part.

 

Questions for the experts:

 

(1) Can the MAP sensor be cleaned ?

(2) Will outer Barometric (Sp?) pressure impact the readings of the MAP sensor ? We are having some wicked weather in central Texas today...so I am holding out hope that maybe this is possibly causing the issue ? (Or is that a nerf bat statements ?)

[Mike_N_Austin]

Correction to my last update

 

I accidentally disconnected a vacuum hose the other night when I was adjusting the Throttle Position Sensor. I re-connected this hose last night and now the MAP sensor fault is apparantly gone

 

Drove the car 45 miles on this mornings commute....and so far no codes

 

Will see what happens at lunch. But, at this point, looks like knock sensor was the culprit.

[cookie]

No codes is good codes. Good luck!

[Mike_N_Austin]

Last Update...and great end to the story

 

Codes did not come back...and the car passed emissions. I have a new inspection sticker.

 

 

Now...I am considering disconnecting the new Knock sensor because I had much better acceleration when I was getting the ODB fault codes :cool:

[cookie]

Gret mike, but leave it on. The knock sensor detects engine damaging pinging before you can. If money is no consideration go ahead and disconnect it.

[Mike_N_Austin]

Gret mike, but leave it on. The knock sensor detects engine damaging pinging before you can. If money is no consideration go ahead and disconnect it.

 

HA !

 

OK...it is definitely staying on