No Start
#1
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No Start
Hello,
looking for help on where to go next with my diagnosis of a no start on my car. i originally had no spark/fuel. i test my opti and found i wasnt getting a signal voltage from the opti to the pcm telling the ign module to fire the coil. i changed my opti spark, and while i was in there i changed my cam/crank gear and timing chain, and a new water pump. hoping i wont have to open it up for a long time. got my crank dot and cam dot lined up apropriatly, crank at 12 oclock and cam at 6 oclock wiht the dowl at 3 oclock. re installed timing cover, and lined up my dowel going into the back of the opti with the approriate locations. put water pump on, and got everythign back together, thought i was good to go. i went to start it, and i got one good turn out of it where it sounded like it fired then just didnt fire and cranked. now it will crank over and i tested my fuel injectors with noid light and they are firing, check for spark coming out of the coil and its good, and also checked for spark at the cylinder one and it looks good. im lost now as to why my car wont start, alot of money and frustration at this point. hope you can help me guys. thanks in advance
looking for help on where to go next with my diagnosis of a no start on my car. i originally had no spark/fuel. i test my opti and found i wasnt getting a signal voltage from the opti to the pcm telling the ign module to fire the coil. i changed my opti spark, and while i was in there i changed my cam/crank gear and timing chain, and a new water pump. hoping i wont have to open it up for a long time. got my crank dot and cam dot lined up apropriatly, crank at 12 oclock and cam at 6 oclock wiht the dowl at 3 oclock. re installed timing cover, and lined up my dowel going into the back of the opti with the approriate locations. put water pump on, and got everythign back together, thought i was good to go. i went to start it, and i got one good turn out of it where it sounded like it fired then just didnt fire and cranked. now it will crank over and i tested my fuel injectors with noid light and they are firing, check for spark coming out of the coil and its good, and also checked for spark at the cylinder one and it looks good. im lost now as to why my car wont start, alot of money and frustration at this point. hope you can help me guys. thanks in advance
#2
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Hello,
looking for help on where to go next with my diagnosis of a no start on my car. i originally had no spark/fuel. i test my opti and found i wasnt getting a signal voltage from the opti to the pcm telling the ign module to fire the coil. i changed my opti spark, and while i was in there i changed my cam/crank gear and timing chain, and a new water pump. hoping i wont have to open it up for a long time. got my crank dot and cam dot lined up apropriatly, crank at 12 oclock and cam at 6 oclock wiht the dowl at 3 oclock. re installed timing cover, and lined up my dowel going into the back of the opti with the approriate locations. put water pump on, and got everythign back together, thought i was good to go. i went to start it, and i got one good turn out of it where it sounded like it fired then just didnt fire and cranked. now it will crank over and i tested my fuel injectors with noid light and they are firing, check for spark coming out of the coil and its good, and also checked for spark at the cylinder one and it looks good. im lost now as to why my car wont start, alot of money and frustration at this point. hope you can help me guys. thanks in advance
looking for help on where to go next with my diagnosis of a no start on my car. i originally had no spark/fuel. i test my opti and found i wasnt getting a signal voltage from the opti to the pcm telling the ign module to fire the coil. i changed my opti spark, and while i was in there i changed my cam/crank gear and timing chain, and a new water pump. hoping i wont have to open it up for a long time. got my crank dot and cam dot lined up apropriatly, crank at 12 oclock and cam at 6 oclock wiht the dowl at 3 oclock. re installed timing cover, and lined up my dowel going into the back of the opti with the approriate locations. put water pump on, and got everythign back together, thought i was good to go. i went to start it, and i got one good turn out of it where it sounded like it fired then just didnt fire and cranked. now it will crank over and i tested my fuel injectors with noid light and they are firing, check for spark coming out of the coil and its good, and also checked for spark at the cylinder one and it looks good. im lost now as to why my car wont start, alot of money and frustration at this point. hope you can help me guys. thanks in advance
Is a splined or non-splined drive opti?
What brand replacement did you use?
Have you tested your fuel pressue?
#3
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I have a 94 lt1 in my car, i believe its what you would consider a splined opti. i got a delphi optispark. and when i tested my fuel pressure at the shradder valve ive got about 42 psi
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I thought the timing was electronically controlled on the lt1 engines? and on the splined opti's there is one spot that isnt pointed its more square and in my cam, that was facing 6 oclock, and so when i installed the dowel pin, i had the same spot on the opti facing 6 oclock aswell.
i read another thread, and people were suggesting that maybe it was the ign module/coil/tps. could this be the case with my car? that my coil just isnt producing enough spark to fire of the plugs enough to ignite the air fuel mixture? and how would i test the tps
i read another thread, and people were suggesting that maybe it was the ign module/coil/tps. could this be the case with my car? that my coil just isnt producing enough spark to fire of the plugs enough to ignite the air fuel mixture? and how would i test the tps
#6
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okay guys, think im officially an idiot correct me if im wrong. i believe ive got it 180 off. i tested cylinder one for spark and with my noid light at the same time to see when the injector was firing in comparison to the spark. it turns out im getting spark before fuel, and when the fuel is being injected its when the exhaust valve is opening. so this must mean im 180 off with my crank correct? so when it was timed it was done at #6 tdc compression, vs #1 tdc compression?
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#9
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So you installed your cam dot-to-dot, meaning that your #6 cylinder was at TDC. That's fine. That's how I always install my cams. My car being a '97 means it is a non-splined opti, and you have to put the cam dowel pin inside the hole with the square next to it to have the right timing.
Your's is a '94, so you hae a splined drive opti:
http://shbox.com/1/93-94_opti.jpg
I don't know if you can install the opti 180* off if the opti is keyed. If you can, then it's an easy fix, just reorient the distributor. Otherwise if you can't, then it won't mater if you align your cam dot-to-dot or both at the 12 position. If the opti can only go on one way then something else is wrong. I am unfamiliar with the spline drive, so I can't tell you anything definitive.
Your's is a '94, so you hae a splined drive opti:
http://shbox.com/1/93-94_opti.jpg
I don't know if you can install the opti 180* off if the opti is keyed. If you can, then it's an easy fix, just reorient the distributor. Otherwise if you can't, then it won't mater if you align your cam dot-to-dot or both at the 12 position. If the opti can only go on one way then something else is wrong. I am unfamiliar with the spline drive, so I can't tell you anything definitive.
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^^you are 100% correct my bad I didn't think about it that way as long as you were lined up appropriately when the chain was installed then it doesn't matter where it is when the opti goes on as long as it is in the right slot in the back of the distributor...forget I said anything
#11
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honestly im alittle confused. if i had it all lined up correctly before, then how come i was getting spark before fuel, and the fuel was when the exhaust valve was opening. i thought i should be getting fuel then spark? in the manual i was reading it said to set cylinder one to tdc compression, and then line up the dots at crank 12, and cam 6.
#12
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okay guys, got my car running tonight, well sort of. my car fires right up now, but it runs for about 3 seconds then shuts off, start it again and same thing, any ideas?
#13
maybe you bought a bad opti it happens alot since they are remanufactured mine went out tonight and ive only had the new opti on for 2 weeks **** me man i paid my gm guy to do it because im so busy so now im going to have to pay labor again i wish i had free time
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Check that you have the spark plug wires hooked up to the correct terminal on the optispark. If you're getting spark and it's kicking for 3 seconds you must have timing. That leaves fuel, possibly an EGR valve stuck open? Try depressing the diaphragm and releasing it to see if it makes a difference, it can't hurt. Something very simple is eluding you, it can't be much.
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Check that you have the spark plug wires hooked up to the correct terminal on the optispark. If you're getting spark and it's kicking for 3 seconds you must have timing. That leaves fuel, possibly an EGR valve stuck open? Try depressing the diaphragm and releasing it to see if it makes a difference, it can't hurt. Something very simple is eluding you, it can't be much.
if i have my egr and all emissions stuff tuned out, but i didnt make an egr block off plate would that do it? i wasnt sure if i had to make a plate since its tuned out
#19
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no the old egr is on there, so it "visually" passes mass inspection, there are no openinings on the intake i have found, i actually found that my MAF was not secured well and was letting alot of air in behind it. and it would stall it out. i secured it better, fired it up and it ran good, then let it sit and idle, but it doesnt like to idle. im not sure how big an impact it has, but i dont have my 02s plugged in yet, cuz i havent done my exhaust just headers, so could this affect my idle quality?