93 Astro
Ron in hollis
05-13-2006, 04:53 PM
Backfires thu carb. Runs well Idles well, Pops back under light accelration, Will clear out under the heavy foot. Warm, Cold doesn't matter. Doesn't do it all the time. Changed air filter and PVC, gas filter tommorow. ?
Thanks
Thanks
Blue Bowtie
05-14-2006, 01:42 PM
Carb? On a '93? I thought that '93 was the change-over year from TBI to CPFI, neither of which used a carburetor. Do you mean "throttle body? They each used those.
It could be lean backfire, and a clogging fuel filter can contribute to that. However, if you are "under the heavy foot" and it runs normally, that would tend to rule out fuel delivery TO the injection, but maybe not rule out the injection system completely. It may be injectors that are clogging, streaming fuel instead of producing good atomization, or may be an ignition/timing issue.
What fuel system IS it, anyway?
It could be lean backfire, and a clogging fuel filter can contribute to that. However, if you are "under the heavy foot" and it runs normally, that would tend to rule out fuel delivery TO the injection, but maybe not rule out the injection system completely. It may be injectors that are clogging, streaming fuel instead of producing good atomization, or may be an ignition/timing issue.
What fuel system IS it, anyway?
Ron in hollis
05-14-2006, 09:06 PM
Carb? On a '93? I thought that '93 was the change-over year from TBI to CPFI, neither of which used a carburetor. Do you mean "throttle body? They each used those.
It could be lean backfire, and a clogging fuel filter can contribute to that. However, if you are "under the heavy foot" and it runs normally, that would tend to rule out fuel delivery TO the injection, but maybe not rule out the injection system completely. It may be injectors that are clogging, streaming fuel instead of producing good atomization, or may be an ignition/timing issue.
What fuel system IS it, anyway?
Sorry about that. Mine is the Z vin which is TBI. Filter didn't help. You may be right about the injectors. appears to be a lot of varnish on the throttle body. Never thought about streaming, always thought about leaning out with clogged or dirty injectors.
Let you know what it is.
Thanks
It could be lean backfire, and a clogging fuel filter can contribute to that. However, if you are "under the heavy foot" and it runs normally, that would tend to rule out fuel delivery TO the injection, but maybe not rule out the injection system completely. It may be injectors that are clogging, streaming fuel instead of producing good atomization, or may be an ignition/timing issue.
What fuel system IS it, anyway?
Sorry about that. Mine is the Z vin which is TBI. Filter didn't help. You may be right about the injectors. appears to be a lot of varnish on the throttle body. Never thought about streaming, always thought about leaning out with clogged or dirty injectors.
Let you know what it is.
Thanks
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