i have a 90 vette that i bought not running so i dropped a 383 stroker in it. the car runs but not like it should, my first thoughts were bad gas and after draining it the car ran better but still very bad. When i start the car and it has sat for awhile it will fire and then die, if you hold the gas it will stay running. Once the engine has warmed up it will idle high and then low. If i put it in gear the rpms drop very low and it will almost die, if i drive it like theres no tomorrow and stop it will idle fine in or out of gear. I have replaced the vaccum lines, checked various sensors and still can't figure it out. the tach and spedo. do not work could that have something to do with it. PLEASE HELP!!!

Is it using injection or a carb? It may be bad injectors. Have you checked the fuel pressure that may be something to look at. It wouldn't surprize me if thats where your problem lies. There are some injector shop that you can send your injectors to and they can test them. Hope thia helps;)

This is only a wild guess but cheque your fuel pump presure,it may not be holding constant .This could also be a slightly blocked fuel filter,again only a guess.Good luck

JUNKVETTE I hope you get it fix!! Keep us informed!! Tim c5garage

well i read some where that the t.b. gasket could be leaking, when i pulled it off someone used rtv instead and it was blocking the vaccume port. When i replaced the gasket it ran alot better and tried to stay running when cold. I havent checked the injectors or fuel pressure but i did notice that the o2 sensor was not pluged in and the connector was melted, I know i need to fix it but could this be some of my problem. Also tried reading the codes through the car and it would just flash sys... anyone know what this means? What should the pressure be at?

I think you have a great deal more problems then what you first started with.Yes you will have to repair the O2 sensor,without it your fuel system will be trying to adjust for faulse reading from a non conected sensor.If the conector is melted it usually indicates a ground fault,probably in the past O2 sensor.I would replace both.Your car code system may be overwhelmed by the number of faults that are occuring,you might be advised to take it in and get a complete cheque at a dealer before comiting too much money in the wrong directions.At least you will know all of the interlinking problems.Best of luck and let us know what happens.

well the o2 sensor was obvious that it needed fixed.. it was melted from where i forgot to connect it and it hit the manifold. If I were to take it to a dealer then i would be commiting way more money than i would if i tried a couple simple test.

You may be right but it may still be a consideration.If your O2 sensor is not conected it will give faulse readings to th computer .It will give corections to the fuel supply that can cause some of the problems.Also if the tac is not working it too can send faulse readings causing your problems.Another problem may occur in a ground fault that could damage the computer as well,the list can go on.I do wish you luck,let me know how it goes.

well i changed my IAC motor and fixed the o2 sensor and it helped but still not right anymore ideas