Hi,
I'm new to the board.
I have just aquired a 1982 Crossfire from my Brother who just passed away on Dec 28th. The car had not ran since 05. The problem is that it Idles very high at around 3000 rpm. The check engine light flashes intermitently. Sometimes the rpm will drop down to below 1000 rpm, but the idle is extremely rough, before the engine expires.

Anyone have any ideas?

 

Real sorry to hear about your brother. Because of the period of setting, I would say you have a vacumn leak. These cars are know for it. The intakes usually leak first, loose bolt or just bad gaskets. It's cheap to fix. Also if the engine light is on check to see what code it is throwing. That will definitely help. I have an 82 and it did the same when I bought it, bought a Felpro gasket kit, replaced the intake, plenumn, and gaskets under the throttle bodies, retimed it, problem solved.

 

Go ahead and replace the Coolant Temperature Sensor as this also fools the engine into thinking it is cold.

They age, just replace it and youll have much better idle control properties.

Also look for the vacuum leak in any of teh fittings, headlight system, brake booster vacuum.

Start isolating each system out of the loop until the issue goes away, that is after you check the manifold upper plenum bolts for torque and spary around them with carb cleaner to look for idle changes.

Its really an easy system to deal with once you read up on it and know fuel injection basics. Just a TBI fuel injection set-up with 2 TBI's.

 

Thanks to both of you. I will try your ideas this week-end.
Regards,

 

Daleman, sorry to hear about your brother but lets keep his memory by getting that Crossfire running sweat After you finish that gasket and sensor you will need to run the car through several run and stop engine cycles. Because the car sat a long time the ECM is in learn mode. If the car doesn't settle down, run a check for any codes. Good Luck

 

another problem that makes them run dirty rich is the rubber hose that bloats . used to couple the pump to sender . wont cause the high idle like the vacuum leaks mentioned before but man do they run like crap when they loose fuel pressure

 

Thanks for the reply guys.
For some reason, the idle was running a little under 1000 rpm today. It stalls after running for a few minutes. I sprayed carp cleaner around the throttle bodies, and around the manifold bolts, but could find no Vacume leak. The check engine light code is 12 or (1 flash pause 2 flashes). I am told that a vacume leak can throw the code off. The engine runs real rough, and I can smell unburned fuel in the exhaust. I plucked the vacume hose off of the EGR valve, but I couldnt detect any suction, and the engine didnt run any different. I did order a new EGR just for poops & giggles. I wanted to tighten the manifold bolts but havent been able to obtain the torgue specs.

 

Almost forgot to mention that I did replace the fuel pump, filter bag, and new connector hose. I remember my brother telling me that he thought that the Vette wouldnt start because it had a bad fuel pump. So that was the first thing I went after. It turned out that the pump got disconnected from the sending unit and that black coupler hose was nowhere to be found. I imagine its floating around in the tank.

 

Code #12: Normal System No Codes.
Code #13: Oxygen Sensor Circuit:
Code #14: Coolant Sensor Circuit Low.
Code #15: Coolant Sensor Circuit High.
Code #21: Throttle Position Sensor High.
Code #22: Throttle Position Sensor Low
Code #24: Vehicle Speed Sensor.
Code #33: Manifold Absolute Pressure Sensor Signal High.
Code #34: Manifold Absolute Pressure Sensor Signal Low
Code #42: Electronic Spark Timing.
Code #43: Electronic Spark Control..
Code #44: Lean Exhaust Indication.
Code #45: Rich Exhaust Indication.
Code #51: PROM Error.
Code #55: Defective ECM.

I pulled these off a quick search. I assume correct, and dont have my book handy.

Keep looking for vacuum leaks. Could be a faulty ECM? maybe. May still be an aged CTS drifting and fooling your engine into running rich and high, since your not finding any vacuum leaks.

You could try to get yourself set-up with an ALDL cable and go out an get WinALDL free software online. (Just googe search it). You then need to learn what is good and what is bad, but it will tell you where your sensors are at.

Also is the throttle position sensor at .525 V at idle?

 

Torque spec is 20-34 ft.lbs for the lid.

Code 12 should have flashed 6 times. 3 at the beginning to tell you its pulling codes....then any codes come in the middle....the 12 three more times to tell you the check is complete. If it flashes 12 six times them there are no codes stored. If you got a engine light flash at any point while it was running there must be codes stored.

Jim

 

I cant seem to get any other code but 12.

 

Does it flash code 12 six times?

It must be something. You said it flashes intermittently. When does it flash intermittently? I assume its after it drops below 1000 rpm and is about to stall. If this is the case its normal. As its stalling the ECM notices low MAP pressure and flashes the engine light. Now if its flashing intermittently while idling at 3000 rpm thats something else.

You are early into this. Don't make any adjustements to anything you will just make things worse. You need to find out which sensor is causing this problem Unless someone has already gotten to the engine and messed with it...any evidence of this?

For starters make sure your radiator is full. If you had to change anything I would start with the CTS (coolant temp sensor) at the front of the engine.

The most likely cause is the IAC's are not working.Each TBI has an IAC...its the cone shaped things near the base with wires going to them. With the air cleaner off you can look down a hole to the left of each injector which is where the tips of the IAC's cycle in and out. As the car warms and the idle drops can you see the pins cycling in and out? If not and
if there has been no power to the ECM for a couple of years you need to reset them. To reset them you need to get the car to drive for about a mile at 35 mph.

Jim

 

Hi Jim,
The Check enging light flashed without any pattern regardless of rpm. The car ran pretty good the first time I ran it after replacing the Fuel pump & Filter. I drove it about 3 miles total, to the gas station & back. I filled it with 91 octane. The next time I started it, it ran at 3000 rpm. For some reason, it doesnt do that anymore. It runs at low idle, but its rough. I can see both spray cones of fuel entering the throttlebody. The flow appears to be intermittent, but each TBI is acting the same as the other. If one TBI sputters fuel, so does the other. I can also smell unburned fuel. I changed the EGR last night, but still no change. Could the Coolant temp sensor be bad even though the coolant temp guage seems to be working. Or are they two separate reads.

 

The coolant temp sensor and temp gauge are separate. View the coolant temp sensor as performing the same function as a choke. It tells the ECM I'm cold so raise the rpm. A bad CTS could cause your problem especially if its not idling high to low anymore. I would change that. The other thing is the 02 may have gone south. Two cheap items that are easy to replace. I would start with the CTS. There is a test for it but its more of a pain then replacing it. I think that sensor is about $20. You can also try unplugging it and seeing if it throws a code....or causes a change in performance. Try it you have nothing to loss. let me know what it does.

The problem here is a malfuntioning sensor does not always throw a code. The codes only come if it s bad 100%. So if the sensor is working at 50% you wil not get a code.

I think your problem will be something simple. I stress that you do not mess with any of the settings. It will not help nor solve the problem but rather amplify it.

Jim

 

The TBI's should pulse in sync. That sounds normal.

Its the flashing engine light at any RPM thats weired. I'll look in the book and address this later.

Jim

 

How are you trying to pull the codes? There is such thing as a fault code 12. If thats the case it will flash code 12 something other then 6 times. Code 12 is a problem with the pick up coil in the distributor.

Jim

 

The flashes are not solid flashes. its almost like it is imitating an electrical short, or a few short blips. I should also mention that I replaced the cap & rotor assembly, but not the coil. My code book states that code 12 is a basic geric code that says the ECM is running okay. I will play with the code reader today to see if I can get anything different. I will also locate and replace the CTS today.

Man..... these 82s are a pain in the !@#$%&. My Bro is laughing his *** off at me right now.

 

It could be a short. Check the red wire in the battery compartment before and after the fuse. While you are at it check the fuse too.

As you may already know pulling the fuse for 10 seconds clears the codes.

Try the CTS and see what happens.

I would get your bro to hang onto one of the distributor wires while you crank the engine....lets see if he is still laughing after...

Jim

 

You wouldnt happen to know where that CTS is would you? I see something like the part I bought screwed into the intake manifold next to the radiator hose.

 

Found the CTS and replaced it with the upgrade version. Kragen didnt have the connector, so I have to go to Ventura tomorro to pick it up. Hope it works.