Im going to purschase a scanner so I can get a read out of why my check engine light keeps comming on. The problem is my 84 has a Camaro computer which was put in according to the last owner to help the X ram set up become more responsive. Will I still get accurate code readings from the jack under the drivers side of the dash since my Corvettes brain has been transplanted???

 

You don't need a scanner to read codes. What code(s) are being set? Trouble shoot the problem.

RACE ON!!!

 

You can use a paperclip in the shape of a U or use a code key to jump terminal A and B. Then turn the key a find out the code(s) stored. The SES light will flash 12, three times then the code three times. The fan and other relays and sensor will also be engergized.

You can also purchase a code scanner and do the same thing. Only ability it will give is it will be able to erase the code without disconnecting the battery.

Either way your choice.

 

Before you purchase the scanner verify that it will scan an '84 F-body ECM, as the scanner doesn't care what car the ECM resides in only what model is the ECM.

For example my AutoXray wants to know what year is the car and a specific VIN code number in order to determine which ECM is being scanned. In your case you would just enter the data for an '84 Camaro in order to setup the scanner.

 

So let me get this straight, if I use a paper clip or buy a scanner I MUST GO BY OR PROGRAM MY SCANNER OR READ THE CODES for a Camaro. Im not sure what year Camaro ecm was used I will have to find out as I thought the last owner said a 86 or 87 Camaro.

 

Step 1.) Use paper clip and read the codes.

Step 2.) Trouble shoot the codes as per your FSM.

RACE ON!!!

 

Sorry I read a mod being done and codes and thought you wanted to get engine parameter readouts as well as codes.

Indeed to simply read stored trouble codes the paper clip method does NOT require knowing what version of ECM is present so long as it is the OBD-I style, which is certain since it's off an early-mid '80s Camaro.

 

Thanks for saving me $40.00 on the scanner.The paper clip worked fine. Where do I go from here. Two codes appeared. 44 and 13. 44 according to the FSM is LEAN EXHAUST( guess thats why this thing always stinks) and the 13 is open OXYGEN SENSOR.

 

Check the connection at the 02 sensor. It might be as easy as that. Since you state you looked in a FSM I assume you have one. Follow the troubleshooting steps.

Do you have an exhaust leak before the O2 sensor?

 

Follow the trouble shooting charts in the FSM until they lead you to the problem and direct the fix of the cause. Without looking, to me, "open OXYGEN SENSOR" sounds like a disconnected or broken wire. Possibly fixing that will solve the code 44, also.

RACE ON!!!

 

Oh yeah...start working on the code 13 first. Once that is fixed, it might also fix the code 44. Disconnecting the battery will clear stored codes.

 

Is there anin here?

RACE ON!!!

 

Apparently SO,

POSTED @ 07:22 pmSounds a hell of a lot like what I stated.

POSTED @ 07:02 pmBTW, I didn't even see post #10, when I made post #11

RACE OFF!!

 

ps374, as RRT Vette has already stated (am I echoing too?), fixing the code 13 stands a very good chance of resolving the code 44 at the same time. The ECM uses the "closed loop" feedback from the O2 sensor to determine fuel mixture status and make changes in real-time. The O2 sensor feedback is based on the air to fuel ratio it reads in the exhaust. If the wire to the O2 sensor is open, it cannot communicate with the ECM and the ECM is unable to use "closed loop". The code 44 is probably a default child condition code based on the ECM's inability to get O2 sensor readings because of the code 13 problem.

O2 sensors are good for 50~75k, but they have been known to go bad much sooner. They are sensitive units and the tips can become contaminated in use, creating erroneous feedback values or outright sensor failure. As mentioned earlier by two very good sources (and yet again), follow the FSM guidelines and check for a problem in the O2 wire and connector. If the wiring tests ok, a replacement O2 sensor can be bought at NAPA, Autozone, Kragen, etc. for about $20~$35.

You will need to disconnect the power to the ECM for 10 seconds to clear the codes in an 84 OBD1 and see if your troubleshooting has been successful. (Yes, RRT said something similar as well. But, he told you to disconnect the battery. I cannot say that your 84 has this capability, but at least by 88, the factory was putting an in-line fuse looking component on the battery connections, which when disconnected removes power to the ECM without disconnecting the battery from the car's other systems. Your radio presets remain, but all stored codes in the ECM are cleared. Additionally the later C4s and all OBD2 vehicles allow you to clear the codes with a scan tool. Unfortunately the early OBD1 systems just don't have that capability, whether you use a scan tool or paper clip.)

 

I checked the wire to the 02 sensor it all appears good, no breaks or cuts and the connection seems good. Can a bad sensor go bad in a open position and would it cause a tempory check engine code as the light goes off after about 5 to 7 minutes and then may come on again for a short time. Sometimes it does not come on at all? My second concern here is the X Ram set up on this vehicle. The X ram has NO EGR valve, and the cat in this car has been cleaned out. Im wondering if this would be giving the 02 sensor faulty info. Im wondering if other X Ram owners are having check engine light temporary failures also?

 

[QUOTE=RRT vette]Sounds a hell of a lot like what I stated.[QUOTE]It shares an idea. I went further suggesting he check all the wiring, not just the connection. Also, I was the one that brought up the idea that curing the code 13, might also take care of the code 44.


I thought *I* was the slowest typist on here. Generally I will see a post 15 minutes before leaving the post to author a two liner. And the way your post started. "Oh yeah...start working on the code 13 first.", right after I had said the same thing, sure makes it look like a "me too" post.


How clever...and original.

RACE ON!!!

 

Have you followed all the steps in your FSM to trouble shoot the codes? You've looked at the wire and it looks good. How nice. Now, what about the rest of the trouble shooting?



I'm wondering if you have you read the FSM? Do you have any idea how the EGR functions? What it does? Where the O2 is located? Where the cat is? The answers to most of these are covered by reading the book. Then, that knowledge with a little common sense, answers most of your questions.

RACE ON!!!

 

[QUOTE=CFI-EFI][QUOTE=RRT vette]Sounds a hell of a lot like what I stated.Whatever.

 

Looks can be deceiving. Just because the exterior seems ok, that means very little. You need to know that the wire inside the protective coating is good and the connection is good. You should use an ohmmeter and test the wire. If you don't have an ohmmeter, you can buy a decent one for under $20 at Radio Shack or Frys Electronics.


No, and Yes. An O2 sensor doesn't "go bad in an open position" like a switch. If it is seen as an OPEN by the ECM, then either the ECM connector is bad (open or broken), the O2 connector is bad (open or broken), there is a break or open in the O2 connecting wire itself, or the O2 sensor went so bad its resistance in the circuit makes it appear to have an open or broken wire. While it could have failed in such a way that it appears to be an open, generally the O2 sensor itself fails at the tip due to an age or contamination problem and that produces an abnormally high or low reading. Given that a code 13 is reported and that you says it is sometimes intermittant, my guess is a problem with the wire from the O2 sensor or the connections.

If you don't know the age of the O2 sensor currently in the car, then given the relatively low cost of a new O2 sensor and the ease of replacing the old one, it might be in your best interest to replace it and see if that solves the problem. CFI-EFI will say that swapping parts is not good troubleshooting and he is absolutely correct. In some cases however, I believe in replacing some of the cheaper parts which wear out, like O2 sensors, when their age is unknown and it may save you more time than proper troubleshooting would take.

The EGR has no operational connection to the O2 sensor that I am aware of which could have the slightest impact in the current situation. Same for the catalytic converter, so unless the guy who put it in disturbed the O2 sensor connection doing it, I doubt that your X Ram has anything to do with this issue.

As CFI-EFI has so eloquently stated, "I'm wondering if you have you read the FSM? ... The answers to most of these are covered by reading the book." If you are going to troubleshoot your Vette, you NEED a factory shop manual (FSM). So much of the help you will get here assumes you have that excellent reference, so as to avoid making the really simple mistakes and wasting your time (and ours). First try reading the manual and if you don't understand something or have any questions, then ask, and I think you will find the answers are more cordial, because we know you are really trying to learn about yur Vette and not just get quick answers to save paying a mechanic. Unlike the other "repair" books out there the FSM is really an excellent reference and well worth the money.

 

I do have the FSM and have read some of the troublshooting issues. However they are talking about testing behind the ECM and grounding certain pins which I not sure about since the car does NOT have the standard ECM but one out of a Camaro.Before I start getting into this over my head( Im not a mechanic but have some knowlege of cars). I do howver know where the 02 censor is and the cat,I think some of these questions adressed to me were more sarcastic then helpful. However I dont want to toast my computer or car so Im cautious.A lot of the normal stuff on most 84s is missing on this car.All the polution stuff is gone and the lines all plugged.I did purschase a 02 sensor and wire for $20.00 and when weather permits Ill give it a try.The car runs like a bat out of he_ L so what ever the last owner did for performance purposes has worked.I just would like to get to the bottom of the occational check engine light. I never used a amp meter and do not own one but Im sure I will be buying a lot of things I never had before.