Fuel Pressure????

astra22bertoneauto

Hi All

Ive had some problems with fuelling the engine lately. I have changed the swirl pot pump & filter and cleaned & checked both lines for good fuel flow.

Problem is lumpy idle & cannot use accelerator as this just makes car stall. When i pinch (not completely, just enough to restrict flow) the return line with some grips, the idle improves & i can rev the engine!

What does this mean? What could be at fault here???

Cheers

vocky

fuel pressure regulator duff ?

astra22bertoneauto

thanks Vocky - I was thinking same thing but wasnt sure.

ATOM_X

I will send correct fuel rail and injectors over
PM me your address

Blue_2_2

That is stagetwocamitus

If you dont remedy the symptoms,
you will end up hating you car,
regretting wasting your money on it (should of bought something with a turbo!)

& end up wanting to get rid of the f#cking thing!

(but then it will dawn on you, your car is unsellable in its current state and the only cure is to break it up for parts)

Have you drilled the throttle body plate?

I ended up buying 5 throttle bodies before i ended up with one that gave me a semi decent idle
And my remap was causing massive over-fuelling, so i made a snap decision to convert back to standard
And guess what ...............it is 99% the same as it was before, but the fuel consumption has improved massively!

This should serve as a warning to others about the perils of fitting stage 2 cams

astra22bertoneauto

That is all very true, but that is the price you pay for modding your car!

5 Throttle bodies is a lot :shock: - I made 2 1.5mm holes and a 1mm hole in mine and although it wasnt perfect it was acceptable.

Luckily all i have is a fuel regulator that is not performing how it should. Engine has been running fine before this with a little popping on idle. I wonder if there are differences between auto & manual on idle with stage 2, and the labour it places on the engine? notsure.gif

BURT150

If the problem is fuel pressure why not use a decent aftermarket FPR with rising rate and drop the prressure down at idle then let the rising rate push 3.5 bar when you exelerate.

get yourself an inline fuel pressure guage and see whats hapening when you touch the throttle that should tell what pressure your getting in and out and tell whats happening with a bit of throttle.

Blue_2_2

You cant get perfect,
too much air and it throws up a code!
Drill a tiny hole.............go for a long drive if its still ok, make it a tiny bit bigger and repeat
Or just ditch it all and fork out for throttle bodies & fit a standalone ecu.......

From what ive picked up, auto boxes are more gentle on bottom ends then manuals, something to do with shock loading
the gubbins inside the box also weighs very little so the engine should be able to spin up faster
generally the autobox is better then a manual, shame it weighs as much as a fat man! (nearly 100kg)

ATOM_X

Blue_2.2 said:
You cant get perfect,
too much air and it throws up a code!
Drill a tiny hole.............go for a long drive if its still ok, make it a tiny bit bigger and repeat
Or just ditch it all and fork out for throttle bodies & fit a standalone ecu.......

From what ive picked up, auto boxes are more gentle on bottom ends then manuals, something to do with shock loading
the gubbins inside the box also weighs very little so the engine should be able to spin up faster
generally the autobox is better then a manual, shame it weighs as much as a fat man! (nearly 100kg)

To think, I am the same as an auto-box, but less complex

astra22bertoneauto

Blue_2.2 said:

From what ive picked up, auto boxes are more gentle on bottom ends then manuals, something to do with shock loading
the gubbins inside the box also weighs very little so the engine should be able to spin up faster
generally the autobox is better then a manual, shame it weighs as much as a fat man! (nearly 100kg)

There is always pros and cons to things. Kinder to the engine but heavier and more power loss. Nothing ever is simples a.

BURT150 said:
If the problem is fuel pressure why not use a decent aftermarket FPR with rising rate and drop the prressure down at idle then let the rising rate push 3.5 bar when you exelerate.

That is a good idea Burt. But are they easy to fit? LMF sell some nice looking ones..... notsure.gif

astra22bertoneauto

Well I found a fuel rail on another z22se coupe this morning, but this rail has the regulator bolted on! Hmmmm... still not bad for £40. Ill post some pics tonight once ive cleaned it up.

Old rail is 1 complete unit and Vx stealers want £286 for a new rail!