V11 LEMANS, 2002 FUEL INJECTION QUESTION(S)

[WRC]

Noticed a couple of things recently with my Lemans that had not been happening. First, it is harder to crank. Have to grind on it for a while when it is cold, been sitting for several hours or over nite. Tried turning the key on, waiting for the pump to stop buzzing, cutting off the key then turn the key on again and waiting for the buzz to stop on the fuel pump and then crank. Seems to do better that way. Have to crack the throttle some to get it to fire up ( has always helped to crack the throttle some when starting cold). Secondly i have gotten a loud back fire when restarting when the engine is hot on a couple of occasions, not everytime. Not sure if it is back firing thru the intake or exhaust but it is loud and sounds like a gun.

 

Could an injector be leaking? Causing the fuel pressure to fall over night or give a very rich mix when restarting hot? Does the fuel pump have a one way valve to keep the pressure up on the system? Have not checked the fuel pressure yet. Still runs good, just don't like having to grind on the engine to get it started.

 

BTW, these issues did not seem to start until after changing the fuel filter and replacing fuel lines. Thanks for any feedback.

 

Bob

[fotoguzzi]

when was the last time you adjusted the valves? most of us do crack the throttle at start up, that's normal. the CPU gives it a rich mix at start up. the pump does not have a stop valve, the regulator keeps pressure up when running with the excess fuel returning to the tank, can you hear it refilling the tank while at idle?

[pasotibbs]

+1 for the valves

 

How does it run when warmed up ?

If it seems "off"(erratic idle etc) it might be worth checking the inlet rubbers for leaks ?