Im STUMPED

[olivedrab]

Originally Posted by rfmaster

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

no i didnt check the fuel pressure before or after. the pump that was in there was still under warranty so i pulled it anyways since it wasnt costing me anything but time and effort, and it also give me the chance to double check everything as far as that goes.

quick question, is there any way to check fuel pressure without an inline fuel pressure gauge? cuz i dont have one of those... but i can get a hold of one.

thanks again for all ure help rfmaster

[rfmaster]

Yea, stock TBI system does not lend itself for ease of fuel pressure checking. Depending on which fuel pressure gauge test set you have it may have and TBI specific T adapter section. Even if you do have an adapter it is a PITA since OEM fuel lines are hard to get to and move in order to insert T section (in the back of TB).
Alternatively, you can insert a 3/8" T and appropriate sections of rated fuel hose at the fuel filter. It will not be as accurate, but it will give you a clear indication if you have low fuel pressure.

//RF