wont start has spark and fuel
Thread Starter
On The Tree
Joined: Feb 2009
Posts: 163
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From: Texas
wont start has spark and fuel I'm running to a dead end every where I look iv read othere threads and still have not solved my problem. Info 1993 z28 new opti, new coil, new icm, and good fuel psi at 40.
I have checked everything the grounds the opti and wires I fuel injectors everything is on right or work right.
I was adjusting the rockers one day got them done car was working fine then the next day I try to turn the car on and it was having a hard time staying on I had to keep my foot on the gas or of I let it off it would idle at 300-400 rpm then just cut out..
So thinking it might me fuel related I put a new fuel filter on the next day and then the car just got worse it would just crank and back fire when I let off the key at the time I had no money so the car say for 2 months. I finally looked at the other day tried to turn it on and nothing just cranks doesn't even pop when I let off the key, it has spark, fuel and nothing so I try some starter spray and nothing I checked to see if the fuel injectors are pulsing and they are I put a new opti and nothing I put my friends icm and coil on and then some progress it back fired out the exhaust and then back fired out the intake then after a couple of more trys it fired up for about 2sec then the battery died so I got it charged and then tryed again and it started to just crank and pop when I let off the key so I looked at the opti thinking its 180 out but it was good tried to turn the car over again and nothing now its back to where I started it just cranks I tryed pulling codes with the paper clip method but my ses light just stays on and my check gages light too with or with out the paper clip in I don't know where else to look could I have burnt out the icm again any help will be good.
I have checked everything the grounds the opti and wires I fuel injectors everything is on right or work right.
I was adjusting the rockers one day got them done car was working fine then the next day I try to turn the car on and it was having a hard time staying on I had to keep my foot on the gas or of I let it off it would idle at 300-400 rpm then just cut out..
So thinking it might me fuel related I put a new fuel filter on the next day and then the car just got worse it would just crank and back fire when I let off the key at the time I had no money so the car say for 2 months. I finally looked at the other day tried to turn it on and nothing just cranks doesn't even pop when I let off the key, it has spark, fuel and nothing so I try some starter spray and nothing I checked to see if the fuel injectors are pulsing and they are I put a new opti and nothing I put my friends icm and coil on and then some progress it back fired out the exhaust and then back fired out the intake then after a couple of more trys it fired up for about 2sec then the battery died so I got it charged and then tryed again and it started to just crank and pop when I let off the key so I looked at the opti thinking its 180 out but it was good tried to turn the car over again and nothing now its back to where I started it just cranks I tryed pulling codes with the paper clip method but my ses light just stays on and my check gages light too with or with out the paper clip in I don't know where else to look could I have burnt out the icm again any help will be good.
Thread Starter
On The Tree
Joined: Feb 2009
Posts: 163
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From: Texas
I am not a 100% but at the time the car was running fine after I was done adjusting them I was actually going to take it to some one to do it right but I know I got them colse I did the exhaust open intake closed method if that's right I don't realy remember if that's what its called but I got them to 0 lash and then turned the a other 3/4 turn...why do you ask if I put too much pre load will it not let the car fire up the least it would let it back fire or try to fire right
I had the same problem for a while. Mine ended up being the msd coil didn't allow my pigtail to fit snuggly and it burned the wires. Make 100% sure plug wires are correct. Also be sure the opti is in correct mine fit in like 3 different slots.
Deffinitly start tracing every wire in you harness for something burned or grounded out.
Deffinitly start tracing every wire in you harness for something burned or grounded out.
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couldve swore i posted in this last night. I had the exact same problem and ended up being fuel fouled spark plugs, so might pull them too and check. I swapped mine out for new ones and fired up first time.
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Verdad Gallardo Thread Starter
On The Tree
Joined: Feb 2009
Posts: 163
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From: Texas
Ok this is the up date I went and got a brand new icm and I also found some cut wires and fixed that so now the car trys to fire up and some time back fires out the intake and also will kick back when I let off the key. I checked the plugs and they are still sparking but they are all black so I put some new ones in and see what it does.
But the new ? is even though the opti is giving out spark can it be bad and give it off at the same time I opened it up to see if the 2 screws cam out on the roter but it was fine...my guess is that the opti is not working right but I need to make sure so let me know what you all think
But the new ? is even though the opti is giving out spark can it be bad and give it off at the same time I opened it up to see if the 2 screws cam out on the roter but it was fine...my guess is that the opti is not working right but I need to make sure so let me know what you all think
opti could be bad. where'd you get it from? I've had two remans that were dead out of the box (optical sensor was bad). took them back and went and got a GM one. problem solved lol
He doesn't have one- he's speed density ('93)
x2. OP, have you pulled the valve covers to look at the rockers? You might have got them close enough to make it run, but then lost adjustment (loose) running it, or got a couple (few) too tight, or a combination of both problems.
x2. OP, have you pulled the valve covers to look at the rockers? You might have got them close enough to make it run, but then lost adjustment (loose) running it, or got a couple (few) too tight, or a combination of both problems.
FormerVendor
Joined: Dec 2010
Posts: 50
Likes: 0
From: Collingdale Pa
I'm running to a dead end every where I look iv read othere threads and still have not solved my problem. Info 1993 z28 new opti, new coil, new icm, and good fuel psi at 40.
I have checked everything the grounds the opti and wires I fuel injectors everything is on right or work right.
I was adjusting the rockers one day got them done car was working fine then the next day I try to turn the car on and it was having a hard time staying on I had to keep my foot on the gas or of I let it off it would idle at 300-400 rpm then just cut out..
So thinking it might me fuel related I put a new fuel filter on the next day and then the car just got worse it would just crank and back fire when I let off the key at the time I had no money so the car say for 2 months. I finally looked at the other day tried to turn it on and nothing just cranks doesn't even pop when I let off the key, it has spark, fuel and nothing so I try some starter spray and nothing I checked to see if the fuel injectors are pulsing and they are I put a new opti and nothing I put my friends icm and coil on and then some progress it back fired out the exhaust and then back fired out the intake then after a couple of more trys it fired up for about 2sec then the battery died so I got it charged and then tryed again and it started to just crank and pop when I let off the key so I looked at the opti thinking its 180 out but it was good tried to turn the car over again and nothing now its back to where I started it just cranks I tryed pulling codes with the paper clip method but my ses light just stays on and my check gages light too with or with out the paper clip in I don't know where else to look could I have burnt out the icm again any help will be good.
I have checked everything the grounds the opti and wires I fuel injectors everything is on right or work right.
I was adjusting the rockers one day got them done car was working fine then the next day I try to turn the car on and it was having a hard time staying on I had to keep my foot on the gas or of I let it off it would idle at 300-400 rpm then just cut out..
So thinking it might me fuel related I put a new fuel filter on the next day and then the car just got worse it would just crank and back fire when I let off the key at the time I had no money so the car say for 2 months. I finally looked at the other day tried to turn it on and nothing just cranks doesn't even pop when I let off the key, it has spark, fuel and nothing so I try some starter spray and nothing I checked to see if the fuel injectors are pulsing and they are I put a new opti and nothing I put my friends icm and coil on and then some progress it back fired out the exhaust and then back fired out the intake then after a couple of more trys it fired up for about 2sec then the battery died so I got it charged and then tryed again and it started to just crank and pop when I let off the key so I looked at the opti thinking its 180 out but it was good tried to turn the car over again and nothing now its back to where I started it just cranks I tryed pulling codes with the paper clip method but my ses light just stays on and my check gages light too with or with out the paper clip in I don't know where else to look could I have burnt out the icm again any help will be good.
Sounds like your valves are adjusted is too tight.
Recheck your valve adjustment.
The engine is more than likely flodded with fuel ! !
Pull the oil dipstick out and smell the oil for fuel.
Pull all you plugs out and replace them.
After you have the plugs out crank the engine dry with THE IGNITION DISSABLED! THAT WAY YOU DONT HAVE A FIRE.
I seen a lot of times the gas can go bad.
Even though it smells like gas it is not.
And check your fuses.
How did you adjust the valves?
I hope this helps.
Last edited by C/Performance; Jan 11, 2011 at 07:13 AM.
Thread Starter
On The Tree
Joined: Feb 2009
Posts: 163
Likes: 0
From: Texas
Yea it helps I'm going to buy some new spark plugs and my oil smells like gas but before all this happened it already smelled tha way because my car was running rich and ill take a other look at the rockers before I spend money I don't need too but thanks for the help
Buying new plugs won't do you any good until you change or figure out what's causing them to foul (unless you just want to waste $$$ on another set just to have them foul out).
On The Tree
Joined: Sep 2010
Posts: 198
Likes: 0
From: Dunedin, Florida
I had a similar problem when I first built my motor the first time I started it it ran real rough and I had to keep my foot on the gas I let the car stall and when I went to start it again the next day it wouldn't start. Then when trying to start the car it would just sputter and backfire if I was even lucky to get that... One of the fuses on the injectors was blown. The car was trying to run on four cylinders.
