Throttle body catches fires and won’t stay running more than 30 secs
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Throttle body catches fires and won’t stay running more than 30 secs
hey, I’m new to this forum. I have a 1991 camaro RS. This is my first time rebuilding a motor from the bottom up. I went to fire it up for the first time and it actually started right up but only runs for a short period of time. If I’m constantly giving it gas it will stay on until the throttle body catches fire. It doesn’t idle very well also
Re: Throttle body catches fires and won’t stay running more than 30 secs
Recheck your firing order, then reset the valves if the problem persists. Sounds like you've got the firing order wrong, so it's firing when a valve is open, or the lifter preload is too tight causing a valve to hang open when the cylinder is firing. Either situation will blow flames out the intake.
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Re: Throttle body catches fires and won’t stay running more than 30 secs
Recheck your firing order, then reset the valves if the problem persists. Sounds like you've got the firing order wrong, so it's firing when a valve is open, or the lifter preload is too tight causing a valve to hang open when the cylinder is firing. Either situation will blow flames out the intake.
Ok im about to recheck my firing order I’ll check back with you all
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Re: Throttle body catches fires and won’t stay running more than 30 secs
Recheck your firing order, then reset the valves if the problem persists. Sounds like you've got the firing order wrong, so it's firing when a valve is open, or the lifter preload is too tight causing a valve to hang open when the cylinder is firing. Either situation will blow flames out the intake.
heree a video of what it’s doing. I took a clip and posted on YouTube
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Re: Throttle body catches fires and won’t stay running more than 30 secs
Sounds like you are just running out of fuel. Do you have fuel pressure when it fires? Seems like it starts with the prime fuel, uses it up then dies. The ecm should turn the pump relay on when it fires but there is an oil pressure switch that will do it too. Timing may be a bit off as well but doesn't sound like the order is wrong.
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Re: Throttle body catches fires and won’t stay running more than 30 secs
Sounds like you are just running out of fuel. Do you have fuel pressure when it fires? Seems like it starts with the prime fuel, uses it up then dies. The ecm should turn the pump relay on when it fires but there is an oil pressure switch that will do it too. Timing may be a bit off as well but doesn't sound like the order is wrong.
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From: Illinois
Re: Throttle body catches fires and won’t stay running more than 30 secs
No worries, its the school of hard knocks. These are the lessons you never forget! I can't say specifics on what it would take to get it to work, if it can. I also can't say Ive heard of anybody doing this using the 305 TBI parts. I would expect injectors, and a tune at the very least. I'm sure somebody will chime in with some more info.
Yes, you could go carb'd, that may be your easiest, least expensive choice at this point.
Yes, you could go carb'd, that may be your easiest, least expensive choice at this point.
Re: Throttle body catches fires and won’t stay running more than 30 secs
The 305 tbi should at least idle a 350. You can take a can of carb cleaner and squirt a bit in the throttlebody while its running. If its a fuel issue, it'll run a few seconds every short squirt of carb cleaner. If you give it a squirt or two every couple seconds it should idle as long as you keep giving it squirts.
If you followed the book method of setting the valves, it frequently results in this kind of thing... Poor idle, dead cylinders, popping and spitting through the intake, red hot exhaust... The books usually say to turn the pushrod while tightening the rocker until it gets harder to turn, then to add another 1/2-1 full turn to preload the lifter. However with assembly lube, and oiled up lifters, blah blah, it's not unusual for the pushrod to turn well after contact. A full turn is usually too much too. Lifting the pushrod up and down until zero lash, and another 1/4-1/2 turn works better for me.
If you followed the book method of setting the valves, it frequently results in this kind of thing... Poor idle, dead cylinders, popping and spitting through the intake, red hot exhaust... The books usually say to turn the pushrod while tightening the rocker until it gets harder to turn, then to add another 1/2-1 full turn to preload the lifter. However with assembly lube, and oiled up lifters, blah blah, it's not unusual for the pushrod to turn well after contact. A full turn is usually too much too. Lifting the pushrod up and down until zero lash, and another 1/4-1/2 turn works better for me.
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Re: Throttle body catches fires and won’t stay running more than 30 secs
The 305 tbi should at least idle a 350. You can take a can of carb cleaner and squirt a bit in the throttlebody while its running. If its a fuel issue, it'll run a few seconds every short squirt of carb cleaner. If you give it a squirt or two every couple seconds it should idle as long as you keep giving it squirts.
If you followed the book method of setting the valves, it frequently results in this kind of thing... Poor idle, dead cylinders, popping and spitting through the intake, red hot exhaust... The books usually say to turn the pushrod while tightening the rocker until it gets harder to turn, then to add another 1/2-1 full turn to preload the lifter. However with assembly lube, and oiled up lifters, blah blah, it's not unusual for the pushrod to turn well after contact. A full turn is usually too much too. Lifting the pushrod up and down until zero lash, and another 1/4-1/2 turn works better for me.
If you followed the book method of setting the valves, it frequently results in this kind of thing... Poor idle, dead cylinders, popping and spitting through the intake, red hot exhaust... The books usually say to turn the pushrod while tightening the rocker until it gets harder to turn, then to add another 1/2-1 full turn to preload the lifter. However with assembly lube, and oiled up lifters, blah blah, it's not unusual for the pushrod to turn well after contact. A full turn is usually too much too. Lifting the pushrod up and down until zero lash, and another 1/4-1/2 turn works better for me.
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