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Discussion Starter #1
i have a 1982 crossfire that is all stock bought the car about a year ago, the car is a work in progress and runs pretty good for being as old as it is. the car has 62k miles i am working on getting it to run good and then i will turn my attention to the cosmetics i rebuilt the tranny replaced the plugs, wires, points and distributer, have put about 1500 miles on it since i bought it only premium fuel two oil changes and for the most part the car runs fair to good once warmed up however, the car is hard to start when it is cold it seems to not be going to a choke start up for the cold start, a couple of times on the cold weather start up the car starts up like a champ with a smooth high idle warm up but that has only happened a couple of times. i am ready to try to isolate my cold weather start up issues but i dont know were to start any suggestions corvette friends i need some help
 

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Something Doesn't Make Sense Here

i have a 1982 crossfire that is all stock bought the car about a year ago, the car is a work in progress and runs pretty good for being as old as it is. the car has 62k miles i am working on getting it to run good and then i will turn my attention to the cosmetics i rebuilt the tranny replaced the plugs, wires, points and distributer, have put about 1500 miles on it since i bought it only premium fuel two oil changes and for the most part the car runs fair to good once warmed up however, the car is hard to start when it is cold it seems to not be going to a choke start up for the cold start, a couple of times on the cold weather start up the car starts up like a champ with a smooth high idle warm up but that has only happened a couple of times. i am ready to try to isolate my cold weather start up issues but i dont know were to start any suggestions corvette friends i need some help

Huh? Your car only has 62,000 miles on it and you had to rebuild it's 4-speed TH700R4 automatic transmission? And '82's don't have points in their distributors because their distributors are computer controlled. Also the Crossfire Injection doesn't have a choke. The air fuel mixture is enriched by the computer that uses the sensor at the front of the intake manifold to detect coolant temperature. To start it just turn the key and crank it because all fuel injected cars are supposed to be started with a closed throttle. And '82's are designed to run on 87 octane gas. And '82's will go 7000 miles between oil changes so why on earth have you changed your oil twice in just 1500 miles? Are you really sure you have an '82?
 

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Discussion Starter #3 (Edited)
1982

yes i am sure it is a 1982, the car sat for a time and the oil was black when i got it the reason for the two oil changes in the short period of time was to help the car clean out, sticky valves etc, probably not necessary, the car is not burning any oil but the car sure did run a lot smoother after the fresh change the second was just to let any crud in the engine help to clean out, what i ment was a new distributor cap only, and positive that it is a 1982 your information is helpful and i will see about that sensor you mentioned
 

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Discussion Starter #4 (Edited)
700r4

and also yea the tranny was shot amco showed me the insides of it worn out for sure, after tracking down the second owner he told me the miles on the car are close to accurate except for a period of time when the speedo was down and from inspecting the car close i think it is right ,original shocks, original clamps, all original cross fire, clean sound of engine no knockin or lifter tap, no oil consumption, cant see any evidence that the engine has been out of the car, but maybe i am wrong i know that 700r4s dont die that soon but yea rebuilt tranny from amco and they did a good job. anyway i did learn a lesson to never buy a car from another state and trust someone with out going to see it for myself, anyway i paid 9k for the car ,it is what it is not to bad and i am comitted to it now, the color is gold and the finish is still nice only 648made in this color
 

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Discussion Starter #5 (Edited)
choke

i know the car is not carburated and that the ECM calls all the shots .me using the term choke was just to get the message across that under cold start up the ecm is not getting the correct info to compensate for a cold wether start you follow me gold leader, plus let me humble myself in sayin i am not a professional mechanic but information is the key to making sure that i know were to look thanks
 

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1982 CrossFire Injected Corvette

i know the car is not carburated and that the ECM calls all the shots .me using the term choke was just to get the message across that under cold start up the ecm is not getting the correct info to compensate for a cold wether start you follow me gold leader, plus let me humble myself in sayin i am not a professional mechanic but information is the key to making sure that i know were to look thanks

Okay pumper, I have owned my '82 for 23 years and I can tell you most anything you would ever want to know about the Crossfire Injected engine. For starters there is a temperature sensor that is screwed into the front of the intake manifold about 3" to the right of center. That sensor gives the computer the coolant temperature needed to adjust the air/fuel mixture for cold starts. Then on the firewall behind the power brake unit is your MAP sensor. The MAP sensor reads manifold vacuum and sends that information to the computer. Also there is a throttle position switch (TPS) mounted on the left side of the left throttle body. That TPS gives the computer the amount of throttle opening and should be adjusted to .525 volts. Then there is a O2 sensor just ahead of your catalytic converter and that tells the computer how rich or lean your fuel mixture is. As your engine is "fuel injected" you always start it with a closed throttle. The computer will automatically make your engine fast idle when the coolant temperature is low and will gradually slow the engine down as it warms up. There is a 25 micron fuel filter in the inlet line and it's mounted on the right side frame rail right under the passenger's feet. Your electric fuel pump is mounted inside the fuel tank and it will only run for 2 seconds when you turn your key on unless your oil pressure switch reads 5 psi or more pressure. If the pressure is there the fuel pump will continue to run.

Keep me up-to-date and let me know if you have any other problems. I'll be glad to walk you through them.
 

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Discussion Starter #7
1982

sounds like i ran across the right person for advise thankyou i will check it out and catch up with you down the road for sure.
 

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Can I step into this discussion? I too have an 82. I have done all of the standard plug, oil change, dizzy cap / rotor / coil things to it since I have purchased it last week. I have been spending most of my time reading about the xfire. I have a very rough idle. I am going to check the TPS for the correct voltage thanks to your post above. I also suspect that I may have a vac leak. How can I measure that? I read somewhere that if I pull one of the vac leads off, put a *T* in the line and then a gauge, I should be seeing 15-18 PSI of vac. Any thoughts on that, or the rough idle?

Thanks again!

Rick
 

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Can I step into this discussion? I too have an 82. I have done all of the standard plug, oil change, dizzy cap / rotor / coil things to it since I have purchased it last week. I have been spending most of my time reading about the xfire. I have a very rough idle. I am going to check the TPS for the correct voltage thanks to your post above. I also suspect that I may have a vac leak. How can I measure that? I read somewhere that if I pull one of the vac leads off, put a *T* in the line and then a gauge, I should be seeing 15-18 PSI of vac. Any thoughts on that, or the rough idle?

Thanks again!

Rick
welcome to SV.. and you can jump in anytime you like..rough idle can have numerous causes..if you connect a vac gauge to manifold, it can tell you a lot by its action. Thats what we old guys used before the age of computer diagnostics..this may help, http://www.secondchancegarage.com/public/186.cfm compare your gauge reading with the various scenarios , see what you match.. Toobroke has extensive knowledge of that damn crossfire system..if the trouble is in it, he can help.. he can also tell you about a better option if you want more upper rpm power.
 

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Great! I just purchased a vac gauge today so I am going to go home and check it out. I have soooo much to do with this car, but it is my 5th restoration ... 2 Triumphs, 1 Lotus, and a Porsche. This one, however, is a keeper! I will let you all know what I see. :woowoo:

Rick
 

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Discussion Starter #13
ok i have a ecm coolant temp sensor on the way this cold start issue sucks its cooling here in texas again and my car is not wanting to start in the mornings
 

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Discussion Starter #14
ok i have a ecm coolant temp. sensor on the way its cooling here in texas again and my car does not want to hold idle in the morning and dies, only after fighting with it and it warming up does it do ok
 

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ok i have a ecm coolant temp. sensor on the way its cooling here in texas again and my car does not want to hold idle in the morning and dies, only after fighting with it and it warming up does it do ok

If you haven't replaced the O2 sensor now would be a good time to do it. And while you're under the car replace the fuel filter that is mounted to the frame rail right under the passenger's feet.
 

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Discussion Starter #16
previous owner did away with stock converter, looks like two cherry bombs there now, thin pipe that runs parallel to exhaust is sealed by weld i hope to re establish connection when i replace exhaust back to stock, would that affect cold start, no sample going back to ecm for air fuel mix right? the exhaust is rich in smell except after warm up other then cold start up problems the car runs like a top
 

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Sensors Are Necessary

previous owner did away with stock converter, looks like two cherry bombs there now, thin pipe that runs parallel to exhaust is sealed by weld i hope to re establish connection when i replace exhaust back to stock, would that affect cold start, no sample going back to ecm for air fuel mix right? the exhaust is rich in smell except after warm up other then cold start up problems the car runs like a top

When your engine first starts the coolant and O2 sensors will tell the ECM to make the fuel mixture rich (open loop) until the coolant and O2 sensors tell the computer to go to a leaner condition (closed loop). If a hot exhaust temperature isn't maintained the computer will go back to an open loop and enrichen the mixture again. So it's very necessary to have both of the sensors functioning all the time. The computer used in the '82's and '84's make fuel and timing adjustments at 80 times per second but the later cars had computers that made several hundred adjustments per second.
 

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O2 Sensor

Previous owner did away with stock converter, looks like two cherry bombs there now

As the O2 sensor MUST be functioning you'll have to get rid of those glass packs and put a catalytic converter back on with an O2 sensor mounted in the converter's inlet. The O2 sensor is a very necessary sensor as it tells the computer how lean or rich the fuel mixture needs to be.
 

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Discussion Starter #19
thats what i thought i was looking at the exhaust systems on corvette central and did notice the inlet on the catalatic converter not sure were the 02 sensor is i just need to re establish the connection how does the 02 sensor connect to the converter and were is the electrical connection for the ecm
 

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Discussion Starter #20
i see that the line from the converter goes into the engine compartment, and you said sensors i see in the engine compartment what looks like two of them brass looking one direct from the converter line and one off the exhaust manifold am i looking at the o2 sensors
 
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