Hey guys, i've been having some bogging problems and decided to tune up


Parts new

Autolite Platinum Plugs Gap .60" ( Book info )
NGK 8mm Wires
MSD OEM Replacement Ignition coil

Previous owner said he changed the Cap and Rotor...

Should i go and buy AC Delco plugs?
MSD coil helped alot... like alot but its still having some hesitation

any hints ?

Thanks everyone

 

Hi, did you check the fuel pressure, the 4.3l L35 engine which has the SCFI needs around 55 to 60psi to run without misfireing. The poppet valves on the spider injection system are made to open around 40 to 45psi, unless you have the LU3 engine which is the MPI spider injection.
The regulators are well known to fail and either leak fuel into the plenum area or back into the return in the injector assy.
Check you fuel pressure it should go up to 60psi when your fuel pump is good. And should stay pressurized for awhile around 50psi after the fuel pump is off and engine not running. If the pressure drops right away there is a leak somwhere.
Some signs of leaking fuel pressure regulator is hard to long start condition.

 

imma let my buddy know this ... his zr2 takes 5 seconds of cranking to start

 

mine starts within half a second when you turn the key

How do i check the fuel pressure ? and also could it be a clogged fuel injector ?

 

i gotta get a pressure tester and check his out

 

Well than I would check the vacuum there could be a leak somewhere in the vac system. Vac leaks can cause bogging, hestitation and staws.

 

Yes, I would get a fuel pressure tester before you gohead and open the plenum. Does your buddy have the L35 or LU3 engine RPO, it will be listed in the glove box

 

how much hose should i buy of the 2 sizes to just replace em all.. the 5/16 and the 7/32... are there any other i should know about

 

r0k0, I would check your vacuum lines before you check fuel presure since yours starts quickly

mrkevinmjr, I would get a fuel pressure tester before you gohead and open the plenum. Does your buddy have the L35 or LU3 engine RPO, it will be listed in the glove box

 

imma have to ask him tomorrow cause hes lazy and home and wont freakin answer me... ill get that tester