[bombasticParticipant bombasticHolden Commodore VR Wagon View build HERE Member since: September 11, 2016 Posts: 3]

Hi Manny

Changing standard items on injection systems brings up problems of a wierd nature sometimes. But knowing how a problem that would develop on the standard for your car might reveal a mod issue that can be worked around.

For example I am noting that you are using non standard fuel pressure regulator. In standard set up if the fuel pressure regluator develops a leak in the units internals fuel will leak up the vaccum control line.

The symptoms might be; starts well cold  because the fuel/oxygen mix is richer but starts poorly in warm or operating temperature.

To test; Depress accelerator pedal slightly during cranking/starting, when engine is at operating temperature or warm day. If engine starts the fault is confirmed/maybe.

If engine exhibits rough idle after starting it also could indicate the same problem. But generally once running after a 20 seconds all is well.

To see proof of this problem, if you disconnect the vacuum hose to the regulator after the engine has been turned off for an hour or two, a little fuel will flow from the vacuum line hose. No fuel should be present. (Care not to loosen any pressurised hoses)

After the fuel has come out of the vacuum hose the engine should start even when hot. (Caution; Beware fuel ignition in engine bay should fuel contact sparks or exhaust manifold. Ensure Ignition switch is tured off and not in accessory position before disconnecting fuel pressure regulator vacuum hose)(Fire extinguisher is handy)

Note; If installing non standard units/regulators it is essential to correctly connect any inlet and return hose to allow for flow in and out in any modification. Any standard hose just blocked off will cause issues in flow. It may also prevent the ability to diagnose problems.

In old cars more than five years old. Crap fitted by Holden to new cars can be vacuum hoses that simply fall away behind the fuel filler to fuel tank. Plastic guard may need removal for view. If any fuel return hose leaks it can be a serious safety issue. Although vacuum lines may only leak fuel vapour it can ignite.

Similar problems can arise when there is an inlet manifold leak. Intermitancy of the problem can change on engine temperature. Sometimes green coolant can be seen around manifolds that leak.

My 2cents worth.

Good luck.

 

[bombasticParticipant bombasticHolden Commodore VR Wagon View build HERE Member since: September 11, 2016 Posts: 3]

Hi from me.

[Author]

Posts