I have a 1991 pontiac firebird it was running fine i shut it off and now it wont start i have done everything i can think of but i cant figure it out im a pretty good mechanic i have been working on this car for a long time but im stumped on this one can anyone help me plz

chevy usually cuts the fuel if the V.A.T.S. fails, i have seen some where the spark is also cut. you need to check for spark at the plugs and work backward from there if there is no spark chevy usually cuts the fuel if the V.A.T.S. fails, i have seen some where the spark is also cut. you need to check for spark at the plugs and work backward from there if there is no spark

i have spark at the plugs how hoes this vats come in to play please explain more car was running fine untill i shut it off today check everything i can think of i have spark at the plugs how hoes this vats come in to play please explain more car was running fine untill i shut it off today check everything i can think of

V.A.T.S. (vehicle anti theft system) uses a resistor chip built into the key to send a "code" to the ECM allowing either the fuel pump to run or the coil pack to become energized, sometimes both. when you turn the key to "start" the computer looks for the proper resistance that it was matched to during vehicle assembly. there were many different computers that each had thier own "resistance code" and they were then matched to the appropriate key that had that resistor chip in it. so in effect the computer and key are a matched set. if you replace the key, you have to replace it with one that has the same resistor value built in. same goes for the ecm, if you replace that you would need to have the key with the proper resistance that the ecm looks for. all that being said, if the computer doesnt like what it sees for the key, it wont let the car start. V.A.T.S. (vehicle anti theft system) uses a resistor chip built into the key to send a "code" to the ECM allowing either the fuel pump to run or the coil pack to become energized, sometimes both. when you turn the key to "start" the computer looks for the proper resistance that it was matched to during vehicle assembly. there were many different computers that each had thier own "resistance code" and they were then matched to the appropriate key that had that resistor chip in it. so in effect the computer and key are a matched set. if you replace the key, you have to replace it with one that has the same resistor value built in. same goes for the ecm, if you replace that you would need to have the key with the proper resistance that the ecm looks for. all that being said, if the computer doesnt like what it sees for the key, it wont let the car start.

9 times out of 10 the V.A.T.S. cuts the fuel to render the vehicle un driveable to a thief. the instances i saw with the ignition were on a little bit newer of a vehicle and may not strictly apply to you, but it is still worth looking into. just bear in mind that if you have no spark, eliminate all other posibilities before condemning the vats as it would be quite involved and pricy to have to swap out a computer and key set, not saying it cant be done, but i would explore all other options first. 9 times out of 10 the V.A.T.S. cuts the fuel to render the vehicle un driveable to a thief. the instances i saw with the ignition were on a little bit newer of a vehicle and may not strictly apply to you, but it is still worth looking into. just bear in mind that if you have no spark, eliminate all other posibilities before condemning the vats as it would be quite involved and pricy to have to swap out a computer and key set, not saying it cant be done, but i would explore all other options first.

i have fire coming to the plugs ive check everything i can think of somebody told me that might be the crank sensor is tha possible i cant figur out whats wrong the car was running one minute i shut it off for about 3 hours then tried to start it and it wont start i have fire coming to the plugs ive check everything i can think of somebody told me that might be the crank sensor is tha possible i cant figur out whats wrong the car was running one minute i shut it off for about 3 hours then tried to start it and it wont start

i bought a dionostic tool to check the codes and when i hooked it up it only flashed one then twice i looked in book and it said code twelve but dionostic code reader said that it didnt deteck anything what does that mean i spent a lot of money on this thing what do the flashes mean how do i diognos the probleem can anyone help me i bought a dionostic tool to check the codes and when i hooked it up it only flashed one then twice i looked in book and it said code twelve but dionostic code reader said that it didnt deteck anything what does that mean i spent a lot of money on this thing what do the flashes mean how do i diognos the probleem can anyone help me

is there fuel getting to the engine as well? i know you said you can hear the pump, but is there fuel at the injectors? also is the check engine light on? even though it is a 1991, it still has on board diagnostics (obd 1) and you could pull up the codes to narrow down your search. is there fuel getting to the engine as well? i know you said you can hear the pump, but is there fuel at the injectors? also is the check engine light on? even though it is a 1991, it still has on board diagnostics (obd 1) and you could pull up the codes to narrow down your search.

yes there is fuel getting to the injector i checked the perge vale to see and 5there was presure and yes thecheck engine light is on how do i pull the codes to narrow search on codews yes there is fuel getting to the injector i checked the perge vale to see and 5there was presure and yes thecheck engine light is on how do i pull the codes to narrow search on codews

code 12 just tells you that you reached the par of the computer where codes would be stored. so it woild flash a code 12 then pause, anything other than 12 that flashes would be a trouble code. since yours didnt have anything other than 12, i am going to say that it isnt a problem that obd would look for. code 12 just tells you that you reached the par of the computer where codes would be stored. so it woild flash a code 12 then pause, anything other than 12 that flashes would be a trouble code. since yours didnt have anything other than 12, i am going to say that it isnt a problem that obd would look for.

what else could it be the only thing that i havent checked the spark plugs to see if they might be fouled out because they are so hard to get to but thats the only thing i havent checked yet i did check to see if i was getting fire to the plugs from the coil and distrbuter i have done just about everything i can think of i cant figure it out i even checked the voltage on each fuel injector and they all read 13.1 volts thats what they call for what else could it be the only thing that i havent checked the spark plugs to see if they might be fouled out because they are so hard to get to but thats the only thing i havent checked yet i did check to see if i was getting fire to the plugs from the coil and distrbuter i have done just about everything i can think of i cant figure it out i even checked the voltage on each fuel injector and they all read 13.1 volts thats what they call for

you have fuel and spark, the only other thing you need is air.....does the engine even try to fire at all? is the intake plugged? air filter good, plumbing to the intake ect? you have fuel and spark, the only other thing you need is air.....does the engine even try to fire at all? is the intake plugged? air filter good, plumbing to the intake ect?

yes the engine turns over but wont start everything seems to be fine now the car was low on fuel and it was bogging but i put more fuel in it and it would't start is there a way to reprime the system maybe it was so low that it dried out the system because it is fuel injected or maybe some bad gas i check fuel filter and it wasn;t block at all and fuel looked and smelled fine i didnt see any water on top yes the engine turns over but wont start everything seems to be fine now the car was low on fuel and it was bogging but i put more fuel in it and it would't start is there a way to reprime the system maybe it was so low that it dried out the system because it is fuel injected or maybe some bad gas i check fuel filter and it wasn;t block at all and fuel looked and smelled fine i didnt see any water on top

i believe that engine has coil packs, you will need to verify spark at the plug on each plug. i know they are a major pain to get to, but it has to be verified. you said you had spark at the plugs, did you pull the plugs out and test them that way or did you test between the plug and plug wire.... i believe that engine has coil packs, you will need to verify spark at the plug on each plug. i know they are a major pain to get to, but it has to be verified. you said you had spark at the plugs, did you pull the plugs out and test them that way or did you test between the plug and plug wire....

i stuck a screwdriver in to the spark plug end and had someone start the car to see if i had a spark i stuck a screwdriver in to the spark plug end and had someone start the car to see if i had a spark

the only way to re prime the system is to keep cycleing the key on and off listening to the fuel pump each time...turn it on, let pump run til it shuts off, turn off ignition repeat until when you turn key on pump does not cycle (whole line and fuel rail up to pressure)
then try to start. the only way to re prime the system is to keep cycleing the key on and off listening to the fuel pump each time...turn it on, let pump run til it shuts off, turn off ignition repeat until when you turn key on pump does not cycle (whole line and fuel rail up to pressure) then try to start.

need to pull plug out and test for spark in the plug...possibly fouled out plugs, or defective plugs. all you verified was coil to plug wire. thats not verifying the spark gets into the engine where its needed. need to pull plug out and test for spark in the plug...possibly fouled out plugs, or defective plugs. all you verified was coil to plug wire. thats not verifying the spark gets into the engine where its needed.

i will try that but i dont think thats the problem i think *** mutch as its going to **** im going to have to pull the plugs and check them out what did you think about how i used a screwdriver to check for spark i will try that but i dont think thats the problem i think *** mutch as its going to **** im going to have to pull the plugs and check them out what did you think about how i used a screwdriver to check for spark

as i said screwdriver was ok to test coil and wire function, but in effective for the plugs themselves. as i said screwdriver was ok to test coil and wire function, but in effective for the plugs themselves.

i here you i wasnt driving the car everyday i was just starting it up everyday just to keep things working im trying to understand what could have happen to it after i shut it off it was starting up everyday i here you i wasnt driving the car everyday i was just starting it up everyday just to keep things working im trying to understand what could have happen to it after i shut it off it was starting up everyday

and for good measure i would replace all the sparkplugs with good quality ones for 2 reasons. 1 you know they are new and will have spark...2 theyre a pain in the @#! to get to and since youre going thru the trouble of pulling out may as well not have to do the job again for a long time. and for good measure i would replace all the sparkplugs with good quality ones for 2 reasons. 1 you know they are new and will have spark...2 theyre a pain in the @#! to get to and since youre going thru the trouble of pulling out may as well not have to do the job again for a long time.

i here what your saying i need to pull plugs and check to see if plug is fireing while it is in the plug wire man that sucks its a real pain in the *** to get them plugs out but i will do whatever i have to get this car running i have already spent alot of money trying to figure out this problem and i cant spend anymor thank u for all your help i really apreciate your time i here what your saying i need to pull plugs and check to see if plug is fireing while it is in the plug wire man that sucks its a real pain in the *** to get them plugs out but i will do whatever i have to get this car running i have already spent alot of money trying to figure out this problem and i cant spend anymor thank u for all your help i really apreciate your time

well there is part of the problem... the engine was not "driven" only allowed to idle which can seriously load up the spark plugs with deposits that would normally get burned off during driving. well there is part of the problem... the engine was not "driven" only allowed to idle which can seriously load up the spark plugs with deposits that would normally get burned off during driving.

ha /ha i here you so thats what im going to do first thing tom if that dont work i will lookforward to talking to u again ha /ha i here you so thats what im going to do first thing tom if that dont work i will lookforward to talking to u again

Glad i could help and hope its just the spark plugs for you.. please leave me some feedback and if you have anymore problems just come back to this page and add them and ill respond as soon as i can. Glad i could help and hope its just the spark plugs for you.. please leave me some feedback and if you have anymore problems just come back to this page and add them and ill respond as soon as i can.

could that cause the car to just not start ?i guess so if it was just buildig deposits because it wasnt being driven you are right that would cause the car to just stop starting if the plugs are burned or fouled out im going to pull those damb things out and check them out could that cause the car to just not start ?i guess so if it was just buildig deposits because it wasnt being driven you are right that would cause the car to just stop starting if the plugs are burned or fouled out im going to pull those damb things out and check them out

i gave some feed back and i will check those plugs and let you know how i made out thanx for all your help it has been a pleasure talking to u i will get back to you can you send me your emai so i can chat with you again if i need to i gave some feed back and i will check those plugs and let you know how i made out thanx for all your help it has been a pleasure talking to u i will get back to you can you send me your emai so i can chat with you again if i need to