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rfmaster · 11-04-2008, 08:15 PM

Olivedrab

Did you actually measure fuel pressure before and after swapping pumps at the inlet to TB??? If you are able to keep it running with disconnected CTS it indicates fuel starvation.

Things to look for -

Broken fuel regulator spring inside TB - this will keep fuel pressure low and starve injectors! A simple fuel pressure check will show that. TB needs 11 to 14 PSI for happy operation. Anything below 9 PSI will be trouble. TB Rebuild kit will have a new spring and diaphragm. Pop the torx screws of the top of the regulator and take a look inside. Link below shows what it looks like.
http://members.shaw.ca/betterthanyou...to/fpr/fpr.htm

Clogged injector - take a look a the injector spray pattern at idle. Disconnect one injector at a time see if idle stumble is the same of either injector.

//RF

11-04-2008, 08:15 PM	#15
rfmaster Registered User Join Date: Oct 2003 Location: OC CA Posts: 1,374	Re: Im STUMPED Olivedrab Did you actually measure fuel pressure before and after swapping pumps at the inlet to TB??? If you are able to keep it running with disconnected CTS it indicates fuel starvation. Things to look for - Broken fuel regulator spring inside TB - this will keep fuel pressure low and starve injectors! A simple fuel pressure check will show that. TB needs 11 to 14 PSI for happy operation. Anything below 9 PSI will be trouble. TB Rebuild kit will have a new spring and diaphragm. Pop the torx screws of the top of the regulator and take a look inside. Link below shows what it looks like. http://members.shaw.ca/betterthanyou...to/fpr/fpr.htm Clogged injector - take a look a the injector spray pattern at idle. Disconnect one injector at a time see if idle stumble is the same of either injector. //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)