Hello everyone, I have just joined the forum
I just purchased a 1982 Corvette collector edition that is in great shape except for a problem with the cross fire injection. When you first start the car the engine runs very rough like it needs a choke pulled out this goes on for about 6 to 8 miles gradually improving and then all at once the engine start running great and continues for the rest of the ride until you stop and the engine cools down for two or three hours and then the whole thing starts again. Also it occasionaly acts like it is going to die after doing a 90 degree at moderate speed, this just lasts for a few seconds.
I have searched the forums but I haven't found anyone with the same problem where it corrects itself after driving a few miles.
Thanks for your help and adding me to the forum

 

There are some cross fire experts here, Buccaneer is one of them. Hopefully he will see this and chime in. If not, you could send him a private message.

 

Thank You, I will watch for him.

 

Do you have access to a Scan Tool ? Could be as easy as replacing a bad coolant temperature switch but we’re shooting blind without a scan tool , eBay is a good source for OBD1 scan tools if you don’t have one

 

Thank you Eric, I will try to get one and give it a try.

 

Take some time and read this post maybe it will help ya.

CF Information

 

Well IMO, it sounds by what you posted like a bad CTS sensor, but it could be something else as well. The CTS is "usually" the issue with what you described. Do you get a CEL light at any time while warming up? If you do at any point, all you have to do is use a paper clip and short pins A/B together on the ALDL connector under the ash tray. They are the two pins when looking down on the connector to the lower left corner. When shorted, the CEL light on the top left on gauge cluster panel will start blinking. All you need is key ON, engine OFF to energize the test. Those are the codes in the ECM that were set if any. You will see a short flash and long flashes, count the two for the code. It will repeat as well. ALWAYS troubleshoot the codes in order, not just randomly picking codes and replacing parts. (see my next statement) ---> Also, do you have an 82 GM Service Manual? If you do not have this manual, get one. You will need it for a car that is almost 40 years old to maintain it properly. DO NOT get the off brand manuals ie... Chilton, Hayes etc, they are ALL junk. eBay is a source for the GM manual.

How many miles are on the car? Just curious to get a better idea of what you may be in for in the future due to mileage. When you post back, be very specific on what is happening. Hope this helps you out. One more thing...Here is a handy area JUST for CFI help, it is pretty good and has a lot of information. Forum CFI HELP

 

Thanks Fastazu. I will read it all.

 

Buccaneer
Thank you for your information. The CEL light does not come on at any time, except when you first turn the key on without starting the car so I guess it's working okay
The manual that was given to me when I bought the car was the 1982 Chevrolet Corvette Shop Manual. Should I get the Factory Assembly Manual also?
The car has 62,200 original miles on it.
What happens with the car is when I go to start it when it's cold I turn the key and I let it crank a few revolutions and then I turn it off and crank it again and it starts immediately, but runs really rough. It continues to run rough for a few miles and then it's like someone flips a switch and it runs great until it gets cold again then the cycle repeats itself.
The other thing that has happened a few times is when you turn at a intersection the engine will stumble for a few seconds and then it's fine.
I looked for the sensor and it looks like it is enclosed inside a plastic box, I will remove the box tomorrow and take a look at it to find out what type of connection it has there are two wires going into the box one black and one yellow. is there is a trick to removing the box? I didn't see a clip or latch on it. And thank you for the link you sent me. I hope this all makes sense.
Thank you for your help and patience.
I just added a photo of the sensor. I got the outer box off and there is a black connector with another plastic piece remaining. to remove the sensor do I have to remove the remaining the plastic piece that is shown in the photo and does the sensor unscrew or is there another type of connector on it.
Thanks Again

 

One 'clue' may be the time delay into warming up and running better.

The ECM allows the engine to run 'open-loop' for 3 0secs to a minute in temperate climes....Then it goes 'closed loop' (controlled and starts to run better.)

What is the idle speed in neutral after it goes into closed loop?

Sounds a bit like the fuel pump is not exactly 'making the grade' either.

We're watching!

Unkahal

 

Your picture is the CTS sensor. Seems odd that you are not gets a CEL with a CTS sensor issue, but it is possible. Do you know what your fuel pressure is at the moment? If you have a gauge on it you could watch the pressure and see what's going on each time. I'm not sold on the bad pump idea yet since it doesn't seem to work when cold, but works ok when warm? If the pump was going out IMO, it will be bad all the time in my experience, but stranger things have happened. Still need to know what the pressure is though. Replace the sensor and see what happens first. You could also pull the codes just to see if anything besides 12 comes up as well that has been stored.

 

Tell us the temperature (of the day/morning). Was it cool outside, warm etc?
Also wondering about heat riser malfunction.

Unkahal

 

Thank you for answering my post.
After reading your post I went for a drive and tried to get some better information.
Temperature was 65 degrees
Starting the engine it ran rough with the tach needle constantly bouncing between 600 and 700 rpm Time: 1:21
At the next check it was still running rough improved the tach was at 900 rpm Time: 1:28
At the next check the car was running smooth 700 rpm Time 1:32
I drove an additional 16 miles with no further problem.
Thank you for your help

 

Buccaneer
Thanks for getting back with me. I will get with a friend of mine this weekend to check the fuel pressure, I don't have a gauge to check it.
I want to replace the sensor, but I'm not sure how to remove it. I removed the large plastic cover but in the photo you can see what's left. how do I remove the connector? I was afraid to try and pull it out or unscrew it and i didn't know if the remaining part of plastic was part of the removal process. If you enlarge the photo you can see a lot of corrosion on the exposed wires. This one has two wires going to the connector but I'm really not sure how to remove the connector. Tomorrow I will take the car to Auto Zone and have them check the codes, I do not have a code reader.
Below is the information I sent to L-46 man
Thank you for answering my post.
After reading your post I went for a drive and tried to get some better information.
Temperature was 65 degrees
Starting the engine it ran rough with the tach needle constantly bouncing between 600 and 700 rpm Time: 1:21
At the next check it was still running rough improved the tach was at 900 rpm Time: 1:28
At the next check the car was running smooth 700 rpm Time 1:32
I drove an additional 16 miles with no further problem.
Thank you for your help

 

Pinch the CTS connector on its sides and pull it off at the same time. Get the newer two pin connector and splice it in to your harness, a much better connector. Again, the CTS is cheap and it probably needs to be replaced anyway. Try that first and post if there is any change and we can go from there. I will PM you as well, call me.

 

This is a big thank you to all of you that have advised me and offered ideas to help me with my Cross Fire Injection Problem. And a special thanks to Buccaneer for walking me through the problem. It turned out that the CTS caused all of the issues from poor idle to a very jerky ride and almost dying until it got very warm, usually 6 or 7 minutes. Now from a cold start if starts quickly and settles into a smooth idle and runs like a new car.

Again thanks to all of you.

 

AWESOME! Glad you got it fixed and it is running well again and...thank you for the compliment, I aim to help the CF community when possible.