VS rough on start up, then fine

[PSYKO PHOENIX]

hey guys, new problem in the vs, she turns over fine but after that if i give her a small squirt of gas she burbles and gurgles for a seccond or 2 untill the revs come up between 2-3 grand and then she sounds more normal, it only seams to happen when i havent driven her in a while eg first start up in the morning, or a start up after 2-4 hours of not driving it

im gunna change the spark plugs this weekend, i was just showing my mate at work the problem and noticed that i couldent hear the fuel pump priming and then going, my mate reckons that the ingecters could be dirty

so the plan is, injecter cleaner, spark plugs then if no improvement ill change the fuel pump.

are there any other problems that could be causing this??

also ive got a drive up 2 auckland (about 2-3 hours) to make this friday will driving it with what ever the current problem is do more damage??

all ideas and help welcome

cheers guys

 

[aceventura]

I have exactly the same problem at the moment.

If I haven't driven it for a few days it shudders and runs very rough until the revs go to around 3000 and then it goes as good as ever! The problem has only developed in the last week or so.

No fault codes
Injectors were serviced about a month ago
Can't locate any vaccum leaks unless there is a leak between the injector o-rings and the inlet manifold that seals when the engine is revved?
Resistance of the HT leads seem fine (genuine holden parts ~ 2 years old)
Seconday resistance of the coils seems fine (haven't checked the primary resistance)
NGK plugs are only 3 months old

But I am still not going to rule any of those out. The only things I am unsure of are:

-I don't know how to check the DFI module (and I guess I would get an error code for that).

-Haven't got the equipment to check the fuel pressure regulator or fuel pump. (I know 2 people that have had a fuel pump fail at 170000km and I am nearly there!)

Hopefully this may help diagnose both mine and Psyko Phoenix's problem (if they are the same issue). Any ideas????

 

[PSYKO PHOENIX]

thank god im not the only one hahaha, soulds like well be killing 2 stones with one bird, ill have a crack ath the same things that youve suggested and hopfully one of us will find the cure!

 

[PSYKO PHOENIX]

ok, ive just put a bottle of nulon total fuel system cleaner into her, ill let you know if theres any improvement, as soon as i can tell

next step after this one is to do all the spark plugs, there gettin abit old hahaha

 

[sedate looking]

Look straight to the fuel regulator. These stupid items are controlled via heat from the cooling system. They are renowned for stuffing up, and causing owners to go around the bend looking for the fault.

Another sometime symptom is if you start it, runs rough and blows a heap of black smoke out. It is just fueling the car up too much when cold.If you search Google for an answer, time and time again it comes back to this little pesky device. Not cheap either at around the $120 mark most places.

 

[PSYKO PHOENIX]

so how do i fix the little bastard??

and more importantly were is the thing hiding?

by the way i love your avatar pic thingey!

 

[sedate looking]

For a V6 i would have to check where it is. There is only one way to fix them, replace them.

And thanks for the avatar comment. One of the standard ones from my site.

 

[VS5lTR]

I got a problem like that but mine sounds rough for a few seconds on start up but not when i put my foot on the gas

 

[aceventura]

Look straight to the fuel regulator. These stupid items are controlled via heat from the cooling system.

The fuel pressure regulator is at the end of the fuel rail, at the back of the engine on the drivers side.

This may well be our problem, but to the best of my knowledge they are control by manifold vacuum pressure, not heat from the cooling system. The vacuum control reduces the fuel pressure at idle (high manifold vacuum), and increases the fuel pressure when the engine is working (low manifold vacuum).

 

[big balls]

if ur putting in new spark plugs try platinum plugs they will work heaps better