| Re: hei cap orientation [message #328401 is a reply to message #328379] |
Sat, 20 January 2018 11:42   |
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RF_Burns
Messages: 2276
Registered: June 2008
Location: S. Ontario, Canada
Karma:
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Senior Member |
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You mentioned you have fuel injection and it has been sitting for 4 years. So another cause of the rough idle and maybe the backfiring could be sticking fuel injectors. I had a one of the injectors on an Ebay purchased Rochester TBI that would stick closed causing the engine to run on 1/2 the cylinders. The local injector guy tried 3 times to get it going, but each time it would stick closed, so I finally bought a couple of Standard Products injectors.
To test them, run the engine for 20 seconds or so that there is fuel in the TBI and shut the engine down. Then pull the power plug from the coil so the engine can't start and pull the air cleaner off so you can look down the throttle. Turn the key and you should hear the fuel pump start for a few seconds to build pressure then look down the TBI. You should not see any fuel leaking from the injectors as they should be closed. Then crank the engine for a few seconds and you should see an equal amount of fuel squirt on the throttle plates of both barrels. If so, the injectors passed this simple test. Shut off the key and plug the power connector back into the distributor cap.
If you got a leaky injector or the amount of fuel sprayed is not in balance, remove the injectors and get them cleaned, or replace them.
An injector cleaning place can test them to be sure they are flowing an equal amount of fuel. Remember the narrowband O2 sensor only measures the fuel mixture on one bank of cylinders, so they can be out of balance leaving one bank rich or lean. A wideband sensor is generally installed after the exhaust Y connection and so measures both sides.
Just my farmboy mechanic way of seeing things.
Bruce Hislop
ON Canada
77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC.
1 ton front end
http://www.gmcmhphotos.com/photos/showphoto.php?photo=29001
My Staff says I never listen to them, or something like that
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