engine codes and rough idle???
Thread Starter
Racer
Joined: Mar 2004
Posts: 305
Likes: 0
From: Houston Texas
engine codes and rough idle???
I have kind of a rough idle on my '85 (automatic). But just as soon as I accelerate, it runs smooth as silk. No hesitation. It idles between 5500 and 5900. My "CHECK ENGINE SOON" light is on. I am getting codes 32, 43, and 54. (I know that "code 32" is the EGR.) Could this be the problem? I am NOT getting any fault codes for the throttle position sensor.
Also, having my "CHECK ENGINE SOON" light on, would this stop me from passing my state safety inspection (Texas)?
[Modified by 1slyder1, 5:38 PM 4/28/2004]
[Modified by 1slyder1, 5:39 PM 4/28/2004]
Also, having my "CHECK ENGINE SOON" light on, would this stop me from passing my state safety inspection (Texas)?
[Modified by 1slyder1, 5:38 PM 4/28/2004]
[Modified by 1slyder1, 5:39 PM 4/28/2004]
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
Re: engine codes and rough idle??? (1slyder1)
If the EGR is not functioning you will likely fail the sniffer test.
There are some EGR test procedures on my site that you can perform without much test equipment. FYI, the EGR Temp switch on your '85 is located on the right rear of the engine above the valve cover.
You may need to check fuel pressure at the fuel rail to see if the fuel pump is ok, since you are getting the code 54. Once that problem has been adressed you should reset codes (open the connector in the Orn wire near the battery for about 1 minute) to see if the code returns.
If it does verify base timing is at 6deg BTDC. It that is ok, you could may need to change the knock sensor or the ESC module (located near the side of the blower motor close to the right inner fender well). If you replace the ESC module use the upgrade one listed on my site.
There are some EGR test procedures on my site that you can perform without much test equipment. FYI, the EGR Temp switch on your '85 is located on the right rear of the engine above the valve cover.
You may need to check fuel pressure at the fuel rail to see if the fuel pump is ok, since you are getting the code 54. Once that problem has been adressed you should reset codes (open the connector in the Orn wire near the battery for about 1 minute) to see if the code returns.
If it does verify base timing is at 6deg BTDC. It that is ok, you could may need to change the knock sensor or the ESC module (located near the side of the blower motor close to the right inner fender well). If you replace the ESC module use the upgrade one listed on my site.
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
Re: engine codes and rough idle??? (1slyder1)
ductape, thanks much; I try to give back some of what I've gotten from this and other forums.
1slyder1, I'm surpriced you passed emissions with those issues, but congrats :cheers:
1slyder1, I'm surpriced you passed emissions with those issues, but congrats :cheers:
Thread Starter
Racer
Joined: Mar 2004
Posts: 305
Likes: 0
From: Houston Texas
Re: engine codes and rough idle??? (65Z01)
I had them give me the results sheet from the inspection so that I could see if I barely passed, or passed with flying colors. As it turns out, all of my numbers were real good. Either my components are on their way out, or I'm getting false readings. I still have the rough idle, so I will keep digging 'til I figure out why. I appreciate all of your help. :)
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