Check Engine Light
 

My 1991 Camaro RS 3.1L V6 has a check engine light problem, and it's legitimate. And the elusive problem is getting worse. Here are the symptoms:

1. Bad gas mileage -- Has gone from 21 MPG to 15 MPG.

2. Lags at highway speeds -- I have to keep the accelerator mashed to the floor to keep it at 70 MPH. Certainly, this is where my gas mileage is suffering.

Back in November is when this problem began. I headed it off at the pass by getting new spark plugs. I mean, that's what this sounds like, doesn't it? Well, I changed the spark plugs.

About a month ago, this problem returned. Surely one can't blow through spark plugs that quickly? What a racket the auto parts suppliers and mechanics are running if you can.

For more information on this car, such as its tumultuous history with fuel injectors, please refer to this thread:

https://camaroforums.com/forum/v6-te...lse-new-61827/

flash for trouble codes and let us know what comes up. http://shbox.com/1/dlc2.jpg yours would be the same as a 93

Thanks. You're as helpful as a Chilton's. Mmh.

How the heck is that supposed to help me? See, this is what I hate about repairing cars and the whole car repair industry in general. WHERE THE FRICK DO I FIND THAT DIAGRAM YOU LINKED?

And how do I "flash" for trouble codes? Lift my shirt up at passing traffic? What does that mean?

That's the best you could come up with? "Flash for trouble codes"? You can't give me a direction like, "It might be the fuel anti-matter containment pod"?

Look. I don't drive this car for fun on the weekends and have a boat and a motorcycle on the side. THIS IS MY TRANSPORTATION; THIS IS MY LIVELIHOOD. I'm here out of desperation because I don't want to throw money or time at the problem because it's something I don't have.

So I'll ask again: given the symptoms listed in the first post, what does this sound like to you?

What the bloody hell was all that about? Your check engine light is trying to tell you what is wrong, but you have to flash the codes to find out. Without knowing, you'll just be throwing money and parts at the car till you get lucky, as any one given symptom could be from a choice of multiple different causes.
Here's the procedure: https://camaroforums.com/forum/3rd-g...d-codes-20385/
Here's what the numbers mean: http://www.troublecodes.net/GM/90-91_31V_mfi.shtml

just got home from work, fishing was not good today. if you click the red part of my post http://shbox.com/1/dlc2.jpg you will be taken to a post in a site that will give you directions on how to flash for trouble codes. the same goes for 69's post the parts in red (or different color not sure how your computer will show) are links to other posts or threads at another location, put your curser on the red and click. its called flashing because when you read the codes it is done by counting the number of times the ses (service engine soon) light flashes during the process. this process has been explained so many times that sites have posts that cover it pretty good. instead of posting the pocess over and over we can link you to the proper way to do things and not have to repeat ourselves to the point of burnout.

The symptoms I have listed should be enough elements to figure it out without needing to read the check engine codes. That's my grievance.

But what you have posted has been the most helpful thing I've read on the subject.

Before I go, here's my next question: how do I distinguish, say, a Code 66 from a Code 15? Where's the Rosetta Stone for that?

That's Chilton's-like garbage. It's not helpful whatsoever. It's more a rant against that link than you. What Camaro 69 posted with the pictures of where you can find the box and what it looks like is substantially more helpful.

Like I said, I'm not ragging on you so much as the link you posted. I'll gladly share with you what I have found. Although I think your time would best be spent working on my car for me than fishing. ;)

All right, I went out and read the codes using a paper clip. But, before we begin, let's recap with the symptoms, because I think those are far more telling than what the codes say:

1. Bad gas mileage -- Has gone from 21 MPG to 15 MPG.

2. Lags at highway speeds -- I have to keep the accelerator mashed to the floor to keep it at 70 MPH. Certainly, this is where my gas mileage is suffering.

3. 210 degrees triggers it all -- It's something else I noticed. If the car approaches 210 degrees, the first two symptoms and the check engine light will come on.

Don't forget -- Back in November is when this problem began. I headed it off at the pass by getting new spark plugs. I mean, that's what this sounds like, doesn't it? Well, I changed the spark plugs.


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So I checked the codes using a paper clip. It flashes Code 12 three times, and this is how it did it:

Flash. Short pause. Flash. Flash. Long pause.

Flash. Short pause. Flash. Flash. Long pause.

Flash. Short Pause. Flash. Flash. Long pause.



Then, it flashed me a Code 33:

Flash. Flash. Flash. Short Pause. Flash Flash Flash.

It did this about three more times, so I shut the car off because I figured I had my code. Anyway, here's what a Code 33 is, according to this link:

"MAP sensor voltage was too high for 4.8 seconds when throttle angle was less than 2%."

What the eff? That's causing all of THAT up there?

Anyway, how is the MAP sensor voltage causing that? And how does one fix the problem?

it flashes all codes three times. there may be more codes so better flash again. should flash a 12 again when all codes have been flashed.

chiltons is the simplest repair manual there is. if you liked that your gona love this

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