I am new to the vette world. I just purchased a 1986 vette that has been sitting for about a year. When started it idles rough. It will run decent until it warms up then it starts running terrible (loses power, misses,backfires ect.). Its running very rich and fouls plugs. I put it on a computer and everything checked fine but it showed the mass airflow sensor was shot. I replaced it but it did not fix the problem. Could it possibly be injector problems? I would appreciate any help.
I am new to the vette world. I just purchased a 1986 vette that has been sitting for about a year. When started it idles rough. It will run decent until it warms up then it starts running terrible (loses power, misses,backfires ect.). Its running very rich and fouls plugs. I put it on a computer and everything checked fine but it showed the mass airflow sensor was shot. I replaced it but it did not fix the problem. Could it possibly be injector problems? I would appreciate any help.
Start with a full tune-up, plugs, wires, cap, rotor, ignition coil, then check your idle air control motor. If it still runs like crap check the OHMS of your injectors and assure they are up to par. If that fails, your computer may be shot, which is an easy replacement and around $100.
That is chore number one...no matter what the problem is. After that try a couple gallons of gas and a triple dose of a good injector cleaner. If it starts to run better it's a varnished injection system. You might get lucky and reverse the problem without taking the system apart by dosing it with cleaner.
Or it may be something else entirely, but that might be a good start.
I just got through taking the injectors out and ordering a set from fuel injection conection. I did get the old gas out and put some new in with cleaner but it still ran terrible.
Once the fuel system is all cleaned up start going through ALL vacuum lines...I'd bet money you will find at least one broken/leaking vacuum line.A hand-operated vacuum pump is an invaluable diagnostic tool.
I tuned it up, put the new injectors in it and is running better at high rpms but when I take my foot off the gas it wont idle, it dies. I found a vacum line near the drivers side firewall that is not connected and sucking air. I cant figure out where it goes. Could this cause it not to idle.
I am new to the vette world. I just purchased a 1986 vette that has been sitting for about a year. When started it idles rough. It will run decent until it warms up then it starts running terrible (loses power, misses,backfires ect.). Its running very rich and fouls plugs. I put it on a computer and everything checked fine but it showed the mass airflow sensor was shot. I replaced it but it did not fix the problem. Could it possibly be injector problems? I would appreciate any help.
Is/was the service engine soon light on? If so evaluating those codes should be at the top of your list. If it runs decent when cold, than runs worse once it is up to operating temps, this could indicate a bad engine control device. What happens is once the engine warms to operating temp, the transition from open to closed loop begins. In closed loop, the ECM is controlling the motor parameter based on feedback from the engine control devices.
I also noticed that more than one thread was opened for this issue. I merged them. This will allow all your information to be stored in one location. This will also make it easier for those participating, and anyone in the future that is searching for information on your issue.
Is/was the service engine soon light on? If so evaluating those codes should be at the top of your list. If it runs decent when cold, than runs worse once it is up to operating temps, this could indicate a bad engine control device. What happens is once the engine warms to operating temp, the transition from open to closed loop begins. In closed loop, the ECM is controlling the motor parameter based on feedback from the engine control devices.I also noticed that more than one thread was opened for this issue. I merged them. This will allow all your information to be stored in one location. This will also make it easier for those participating, and anyone in the future that is searching for information on your issue.
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