VQ statesman surging!!! tried everything and help?

[vqstato1987]

computer wont give out a diagnostic's code, just flash's and fan cuts in and out. will do that all day. engine surges when i go past 70 kms when trying to keep a steady speed. i've changed computer, coil, i think all sensers on motor, dizzy, ing module. and it still does it!! its driving me nuts lol. any help or ideas would be great.

[voney]

I'm far from an expert, but have you checked your fuel system? ie Fuel filter, ran some Nulon through it?

[vqstato1987]

yeah its had a new fuel pump. might change filter and get a new set of injectors. a mechanic said it may be thr injectors but still couldn't give me an answer.

[Tree cutter]

Speed sensor maybe? I only say this because i had a problem with my VL when i had it that made it surge badly until i reached 100KPH. The problem was a faulty speedo cable that made the speedo needle flicker and was upsetting the speed sensor. I fitted a new speedo cable and the problem was solved.
Sparkplugs or leads can cause it to surge also.

[vqstato1987]

cheers thats idea, that has cross my mind. might try that. get another speed sensor

[vqstato1987]

just changed fuel filter and fitted brand new injectors. it still surges!! DAMN THIS CAR IS DRIVING ME NUTS any other idea would be great. list of things i've changed
fuel filter
injectors
coil
dizzy
ingition mod
computer
brand new ox senser on exhaust
change ox senser on inlet manifold with 2nd hand one
changed both sensers on thottle body with 2nd hand ones.
i'm running out i've ideas. this is getting abit beoned a joke haha cheers for any help inadvance!

[vn calais manual]

check your ignition leads, and spark plugs.

[Swordsy]

Could be a bad earth, this has been known to cause problems.
Electronincs don't like running with bad earths.

[VrWagz1]

Is your rotor button heaps sloppy, like you've got worn gears. just a thought

and have you changed the fuel pressure regulator yet.

[vqstato1987]

cheers guys, rotor seems ok, and haven't done leads and plugs yet. i've been thinking a bad earth but hoping not cos that means i have to take it somewhere and prob pay heaps for it. with plugs and leads it only does this stupid shit over 70kms so i wouldn't think it would be that, but u never know. it does seem to be lacking the power up in the revs to, and now the engine light stays on all the time now... till i get to 70 kms and it flashs. i think i will be getting leads and spark plugs next pay. my dad thinks maybe the map senser??
with the fuel regulater wheres that? is that next to the fuel pump or on the fuel rail? cheers

[VrWagz1]

Its a small steel cylinder thing up above the back of the motor, it sits just between the passenger side engine cover and the passenger rocker cover it has the rubber fuel lines going in and out of it. Its fairly obvious to see, if you click "My wagon" link in my signature there is a pick in the first post in which you can see it up the back there.

But do the leads and plugs as they are cheap and so is the fuel reg, and try and get a code out of it.

[vn calais manual]

i doubt it would be the map sensor, and if your engine light is staying on, it should be logging a code, are you checking for these the right way?. does it blow any smoke? what colour?

[vqstato1987]

cheers. that fuel pressure regulator seems to be on my drivers side. when i get paid ill get one of them, seen it lacks the power up in the revs it could be that. and doesnt blow any smoke. its a good heathy motor. but when i changed dizzy i had a lot of trouble removing the old one as it was stuck. couldnt even turn it. just build up of old oil gunk or something.
and still wont give a code out. when i bridge the to wires together and turn ingition on engine flashs every second or so and engine fan cuts in and out. and will do that all day.

someother guy on this site i think had the same problem with his vq and all he said was he was gonna change his coil. and thats all that was said about it. dont know if that fixed his problem or not. i've changed my coil that was the 1st thing i done

[VrWagz1]

Little while back, i had issues with top end power. But my car just wouldnt rev over 4500rpm intermitantly, and you could here the motor leaning out as it starved of fuel and got heaps of air. It turned out to be the fuel pump for some reason intermittantly not putting out enough pressure.
To work that out i temporarily installed an electric pressure gauge in the fuel line and i could see the pressure drop when it played up.

So i wouldn't rule out the fuel pump being a possiblity. It is possible it may be worn and putting out odd pressures causing the problem too. Cost me $95 for the pump with tank gasket and filter, but ou can get em cheaper too, i was just in a hurry and got screwed.

[vqstato1987]

i've got a near new fuel pump from a vl six. extrnal. would they run the same pressures? and by the sounds of what u said is there a intank one to?

[VrWagz1]

ahh, you got one of those external jobs. I've never seen a commy wth one of them fitted. But i think there is still an intank one, its a smaller one that just feeds the large external pump. Someone here may correct me here if thats not true.