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rfmaster · 01-23-2009, 12:34 AM

Gas to TB is good. If injectors are not spraying during cranking there are couple of possible problems.

1) Disconnect both injectors from harness. Check the +B (red and green???) injector wire - it should be +12 when ignition key is on and during cranking.

2) If you have +12V on red wire reconnect injectors, get a +12 volt low current test light (or fast DVM). Probe both injector pins (red and green and red and blue - colors are typical, but maybe different) - red should be a steady +12, while the other side should pulse on-off-on during cranking. No pulse indicates that's ECM is not pulling line low. There are couple of possibilities.

//RF

01-23-2009, 12:34 AM	#55
rfmaster Registered User Join Date: Oct 2003 Location: OC CA Posts: 1,374	Re: Tbi swap build thread Gas to TB is good. If injectors are not spraying during cranking there are couple of possible problems. 1) Disconnect both injectors from harness. Check the +B (red and green???) injector wire - it should be +12 when ignition key is on and during cranking. 2) If you have +12V on red wire reconnect injectors, get a +12 volt low current test light (or fast DVM). Probe both injector pins (red and green and red and blue - colors are typical, but maybe different) - red should be a steady +12, while the other side should pulse on-off-on during cranking. No pulse indicates that's ECM is not pulling line low. There are couple of possibilities. //RF __________________ "The Beast" 1975 Chevrolet C20 longbed 350/700R4! with 3inch body lift Dual Flowmasters Super 40's! TBI retrofit completed (2007-07-29) New 383CID (+030) 08-304-8 9.5:1CR x36,005 (2012-12-17)