hi all
was having hesitation problems with my subaru impreza sport january 1997.
cut a long story short when i removed the maf sensor connection it runs ok so bought a new genuine subaru maf sensor ( from subaru ) connected it back up still the same so i bit the bullet and replaced the engine it was running well when fitted so put it into have a full respray onit so been off the road for a while had it back today drove 100 yards and the problem is back hesitation when i accelerate ( holding back ) so dissconected the maf again and runs well and the power is there.
can anyone shed some light on this? ( iv tried changing plugs leads and coil packs )

thanks on advance

 

replacing the engine seems a bit extreme for the problem? have yuou read any fault codes?

 

just got fed up of people telling me diffrent things was wrong so i just changed it hoping it would cure it and it did at first.it was showing fault code knock sensor on my old engine but this engine i put in was running well when it was first replaced but now its been standing a while starting hesitating on acceleration again unless i unplug the maf it runs well then

 

but i had to still use my ecu becuase the ecu that i had out of the car i had the engine out of wouldnt work..
need all the help i can get with this guys please.
will it do harm driving it with the maf disconnected?

 

Not ideal to run with MAF disconnected. I believe you have a furling issue & disconnecting the MAF is putting into a limphome mode allowing it to run better. I would initially look for air leaks & check the O2 sensor along with a fuel pressure check. An emissions test may shed some light on this aswell.

 

iv tried a different lambda sensor init and didnt make a diffrence bud.only time i can get the car to run ok is if i disconnect maf otherwise it wont respond to acceleration it holds back and has no power at all

 

Check emissions to assess the fuelling any MOT station can do this.

 

what would thid point to by doing this please richard?
thanks.
what would you say this problem is

 

Post your emissions results once it's done we need to see if it's rich or lean & lambda readings etc. I would suspect an air leak or failing fuel pump.

 

earliest i can get it tested would be tuesday so will post then,it did run out of petrol last night whilst on tickover so put some in and it started fine after that would this have anything to do with it??

 

Tried changing fuel pump today and the diagnostic test under the steering wheel said code 22 but we replaced the knock sensor reset the ecu and tried moving knock sensor with no joy and reset the ecu and its still the same ( loses power and misfires when hitting acceleration ) Surely someone on here can help me .

 

after the car visited several garages,tuning specialists and changing engine,coil packs,02 sensor,plugs and leads,fuel pump etc etc went into another specialist yesterday and all along it was the cone air filter causing all the issues,took it off put original filter back on and its running as it should so i have now happily put a hammer through the k an n filter and its now in the bin and wont be putting another 1 on any of my cars.

 

Glad you got there in the end. All because of an induction kit !

 

Dred to think what you paid out in costs..just to find out it was an air filter..

 

it was a second hand engine but even still with everything and garage costs it wasnt cheap at all just because of a stupid induction kit.

 

**** me you fitted an engine because of an air filter??

 

yes mate it went to numerous garages and 1 would say knock sensor,1 would say throttle position sensor 1 would say something else and so on and got fed up in the end....so i thought change engine and all would be well but i was wrong but eventually a tuning specialist found it to be the k an n yesterday so runs as it should know and as i said ( wasnt a joke ) i did actually put a hammer throught the k an n cost me alot of money to eventually find it.

 

So you swapped engines and put yur old filter on before firing it up. Could have saved you some hassle if you started it before changing to the cone.

I was thinking the induction pipe was sucking closed.

 

rob if you thought that then you could of said bud i could of tried it then as im not very mechanically minded.i asked several times on here but didnt get hardly any replys so just went about it the way i thought would of solved it but it didnt,
not to worry it seems ok now