vectra b sri 150 loss of power under load

starsilver

Hi,
I have a vectra b sri 150 that has developed a power fault. Fault came about after giving it some extreme welly and now I am stuck and am hoping for some inspiration from you to avoid the main dealers if I can!

The fault is that the power seems to be cut when I accelerate hard, as if it has had the fuel cut off, and then when you lift foot off the gas it will recover and if gently applied the car will run but it wont give me full power just dies temporarily.

I had left the tank to run quite low so originally i thought that the fuel pump may have sucked up some crap and blocked the filter but changed the filter today and it has not fixed it.

I have noticed a couple of things:

The fuel pump appears to be quite noisy, sounds quite a rumble from the tank, never heard one so loud, is it possible its shot and isnt delivering the pressure or flow rate required under load?
The temperature guage seems erratic and I have read on here that it has to thermistors, one for the dash temp guage and one for feeding the ECU with a reading of the engine temperature to calculate the fuel delivery? Is it possible that this is shot and is not providing enough or too much fuel under load?
I disconnected the sensor today and the car struggled to start and when it did it was very lumpy.
I know that the EGR valves can be a bit of a pain - How do I test it?

I have had a look for a fuel pressure regulator on the fuel rail that feeds the injectors and cant seem to find one! am I looking for something that isnt there!!?? Is the pressure regulated at the pump end?

I have only had the car a few weeks and was loving its responsiveness and I am looking for help as I cant believe its happened after gunning it !!

Hope you can help!!

pottsey

does it happen more when there is less than 1/4 tank 20 litres in the tanks if so put more petrol in to half a tank ,and see how you go ,then if its better it will be down to the swirl pot in the tank that is knackered which means a new tank ,i have the same problem with mine i have to keep it above 1/4 tank and its fine, get below and it cuts out splutters etc

starsilver

I have only had the tank up to about a quarter of a tank. It was empy when i test drove it, the garage had to put fuel in it to do the test drive, but i didnt get the opportunity to boot it as most of the test drive was in traffic. I then went to the petrol station after purchaseing the car and i put 20 quid in and it behaved perfectly all the way home, some 25 miles. I have since then only had a tenners worth in and have left it to go down to the flashy light.

Is the swirl pot part of the tank or part of the petrol pump?
its more of a loss of power as if it has the ignition turned off momentarily.

pottsey

yeah the swirl pot is attached to the bottom of the tank ,the fuel pump sits inside it.
like i said stick some more petrol in upto half a tank ,see how you go ,the loss of power as youve described sounds about right ,then it jumps into life again

starsilver

will give it go today the bursting back into life is exactly what it does it stops and kangaroo hops back into life will post later with the result!

starsilver

just to follow up - I filled the tank up to the top this morning and it seems to have cured the issue .. ta for pointing me in the right direction... guess I'm going to have to sort out a new tank at some point..
Cheers

pottsey

cool glad you found the problem,keep it above 1/4 tank and you'll be fine mines been like it for 2 years now :crazy:
if you do get a new tank might be worth making sure you get the right one cuz appatrantely the 2.2 tank is different to all the others ,not sure why.
ive got a 2nd one but just cant be arsed to fit it ,and if i did fit it ,whose to say it will be the same problem

starsilver

ai thats what I thought - guess its a molding issue when they tanks are manufactured and there is no guessing what you get. think I'll get a price for one tho and see how it goes for the mean time. Very impressed with the 2.2 so far tho had 2.5 sri, 2.5 gsi and 2.0sri before but like the mix of the power and smoothness of the 2.2.

nizbang

Hi there im a newby here i am experiencing power loss to my 150 sri found cracked manifold (also warped) and lose studs so have ground and welded manifold used new gaskets etc and now can rev the car gently up to 5000 rpm but if i floor it from idle it just dies and sounds like its fuel starved with that horrible groan they make. Anyway took of the pump cover under the back seat and everything looks fine in the tank but cant get the cover on again its as tho you need 4 hands has anyone got any tips before all my fuel evaporates. Gonna check the pre cat tomoz thats after ive got the pump/tank cover back on i just cant get that big locking ring back on cryb.. please give me some tips please please.

starsilver

I have got a new fuel pump for mine hopeing that its going to cure it. will let you know how i get on changing it and how to get the lid back on the tank

Ben2_2sri

starsilver said:
ai thats what I thought - guess its a molding issue when they tanks are manufactured and there is no guessing what you get. think I'll get a price for one tho and see how it goes for the mean time. Very impressed with the 2.2 so far tho had 2.5 sri, 2.5 gsi and 2.0sri before but like the mix of the power and smoothness of the 2.2.

Same as me mate I prefer the 2.2 to my GSI and I actually think its quicker and is definatly alot smoother. Was well impressed with how quick it picked up speed in 5th gear from 80mph was doing 110mph before I knew it and so much better on fuel. 😃

starsilver

changed the pump today . quite a bit of muck in the guaze on the old one and in the bottom of the swirl pot. cant see anything wrong with the swirl pot and I cant see how fuel from the tank gets into the pot either? the only fuel that seems to go back into it is from the return pipe.
locking was a bit of a sh1t plenty of fairy on the gasket and elbow grease to get the lid on again!

does anyone know how the swirl pot fails? what to look for? seems to be a few people on here with same problem