vts lacking power excessive fuel consumption

[jayjayvts2012]

I have a 2000 vts saxo seems to be doing 15 -20 mpg on harsh driving and 25-30 normal.. the car on very rare occasions does go very well fru 1st and 2nd gear then the power flattens off fru the next few gears. only manages 115mph my vtr was much faster... so far ive tried the following to put it right:
full service inc timing belt..
both coolant sensors
piper 4-1 manifold with de cat and straight fru stainless
all sensors in throttle body apart from air temp sensor
fuel pressure reg and pump
map sensor
standard air box
had it plugged in computer didnt show any faults..
i know the car has had another engine put in but is using origonal ecu???
the car seems to run well but sumtimes when cold will stutter slightly at low rpm
any ideas :wall:

[Heftydanielson]

With the full service did you do the fuel filter? I've seen people miss these on a full.

Make sure with the new exhaust that all the fitments are on correct, seen them put slightly off line and it may not blow but will restrict flow.

Also, try putting some injector cleaner in with a half tank of shell 99oct, this will clear out the fuel system and should make is pick up better.

[jayjayvts2012]

yeah changed the fuel filter and exhaust fits perfect..made it goes slightly better when it does decide to go lol.. ill try the injector cleaner and the fuel cheers... could it be anything to do with the ecu if its had another engine its still using old ecu??

[Heftydanielson]

Depends what the donor car was. Your car is right on the switch over year.

[jayjayvts2012]

aparantly its from a 60k v reg vts....

[Heftydanielson]

it's the single prong ecu then. Try the fuel/injector and see if that helps. Also and other info on the car could help.

[jayjayvts2012]

i think so yeah but all info i could find out was that it was just the engine they got from scrapyard.. didnt come with a loom or ecu or anything just got what info scrapers wrote on side of timing casing.... yeah ill be defo trying the cleaner... ;)

[saxovtrmk1]

What does it run like on idle? Does it splutter as so it wants to cut out when setting off from cold?

[jayjayvts2012]

seems to run perfect on idle... altho sumtimes itll hunt slightly for like ten seconds then go smooth again... when we had diagnostics machine plugged in when it had its hunting session the oxy readings stayed rock bottom until it ran smooth again then it did its normal thing..

[jayjayvts2012]

does it hot or cold smells of overfueling aswell uses rediculas amounts of fuel

[saxovtrmk1]

Go outside un plug lamba sensor take it for a drive

[Heftydanielson]

Have you done the lamba sensors?

[jayjayvts2012]

drive it with it unplugged?? i think its just got the one lamba at end of manifold just before flange... isit suposed to have 2??

[saxovtrmk1]

Just one on vts yes run it with it un plugged mine was doing same as this i run without lamba in and.its cured

[jayjayvts2012]

ok will try it 2 mora.. itll throw engine light up tho wont it?

[saxovtrmk1]

Mine doesnt mate.and i havent got it plugged in been like it months

[jayjayvts2012]

okay mate all try it anyways... fort lamba was ignored on full throttle anywyz?? its very flat in 3rd gear n rest of them v strange

[saxovtrmk1]

Mine was suffering same symptoms very boggy and almost spluttery when throttle flat down changed all sorts and as a guess i un plugged lamba and it worked lol did the hunting thing on idle as well

[jayjayvts2012]

90% of time it drives smoothly though... just slow my vtr was lots faster without a doubt but when it decides it want to go it doesnt half shift.

[saxovtrmk1]

Whats ur temp gauge like mine was running hotter than usual as well

[jayjayvts2012]

usually sits on the marker in middle or at least i thought it did its nearly been going 3/4 way up gauage which they dont usually do i dont think....

[saxovtrmk1]

Am thinking ur lamba is faulty think it makes it run lean so runs hotter mine run loads hotter before i unplugged it.

[jayjayvts2012]

wouldnt a new lamba just fix it then?? dont wonna risk trying one tho there like 90 quid lol

[jayjayvts2012]

when plugged in the lamba appeared to be doing its job though.... only wen it started hunting did readings stay rock bottom until it stopped hunting then readings returned to normal

[saxovtrmk1]

A lamba might cure it but at 90 quid thats why i suggested un plugging it 1st it might be a intetmitent fault with it as mine used to run fine and then have bad days un plugging it is free and worth a try.if ur in a postion to do it now try it then if it cures it order one tmrw

[jayjayvts2012]

yeah supose.. al try it tomorrow when i can see lol thanks

[saxovtrmk1]

Let me no how you get on just seems to have all same running problems mine did.

[Barry123]

wouldnt a new lamba just fix it then?? dont wonna risk trying one tho there like 90 quid lol

With the amount of fuel you're throwing away you'll have saved that £90 in 3 tanks.

[jayjayvts2012]

unplugged the lamba sensor and it made no difference at all to the running or driving, still slow. left it unplugged no light has come on or anything dont understand should run like crap. does it matter if the engine tht has been put in my car is from a vts tht used the multi plug ecu? mines on the single plug i was made aware that it was only the engine that got changed no ecu or loom? :wall:

[Barry123]

If there's no difference it would suggest the lambda is knackered (since the engine appears to behave as if the lambda isn't there, when it is).

Just cough up the £90 and change the lambda

[jayjayvts2012]

ok but what if that doesnt fix it???

[Barry123]

ok but what if that doesnt fix it???

Well you can leave it as it is gobbling fuel.

[Barry123]

You've only got the air temp sensor left anyway judging by your list.

[jayjayvts2012]

ok changed the air temp sensor and lamba n no bloody difference at all :wall:
anymore ideas?? do the injectors ever go wrong???

[jayjayvts2012]

Let me no how you get on just seems to have all same running problems mine did.

still no look mate and ive tried oxy sensor and air temp :wall: