Hesitation. Need Help!!

[Dimonsta]

So the situation is, im getting really bad hesitation when im boosting. It seems as if the second turbo isnt kicking in, like at all. Anyway i took it for a boost tonight after work and wrote down some readings. When i put my foot flat in 3rd, it starts surging and stuttering really bad when i get to about 5500 rpm, so i switch up to 4th and keep my foot flat and it does the same sorta thing at about 5000 rpm, i switch up again and in 5th there isnt any hesitation that i can feel.

When i put my foot flat going 100kph in 5th, once the revs get up to about 4500 rpm it starts stuttering and hesitating as if the 2nd turbo isnt working.

I watched the boost gauge the whole time through gears 3rd 4th and 5th when i boosted from 3rd and the reading was only 0.5 kg/cm2 for all the gears.

Before work i checked the ECU codes and none came up, i reset the ECU anyway and when i went to pull off after the reset the car stuttered really badly at about 2000 rpm in both 1st gear and 2nd so i pulled over and turned the car off and waited a minute or two and started it up again and pulled off, this time there was less stutter but it was still there. When i started it up after work it didnt stutter in 1st or 2nd and drove like it has before.

The car is a 1994 Legacy RS, the speedo reads 177k kms. I got the clutch changed about 1k kms ago and the mechanic also put on a 2nd Hand AFM but this didnt make a difference to the stutter. I changed the fuel filter at 167k kms as well. The only mods i know of on it are the aftermarket BOV and a pod filter.

I have looked this up on here and found that i should try changing the spark plugs, the coils, the fuel pump and the AFM. Im going to change the plugs tomorrow and then ill just have to get ahold of some new coils, planning on changing the Fuel pump asap as well.

Can someone please tell me what else it could be or help me with this as it makes me not sleep at night lol.

[Dimonsta]

It also idles at about 1000 rpm. Also going to change the oil and filter tomorrow if i have the time.

[czar loc]

had same problem, fuel pump was on way out, i would replace that and see bro

[Bugle]

Had similar issues on my BG when the BOV was on the way out (not opening properly) messes with the transition from single to parallel

[Dimonsta]

Changed the oil and filter and also all four spark plugs. Didn't seem to make much of a difference although it starts up better and drives abit smoother but the stutter is definitely there. Going to try and change the fuel pump and the coils. Anyone know where I can get some new coils from?

[Dimonsta]

Took it for a drive today and started stuttering at 3000 rpm in 5th gear ?

[thorpy]

If its done more than 120ks id replace the 02 sensor regardless and see if that fixes it.

[Dimonsta]

What is that lol and where is it located?

[thorpy]

Oxygen sensor / Air-fuel ratio sensor , Located in the exhaust manifold generally by the passengers side front wheel arch.

[Dimonsta]

Could I get a picture of that please?

[thorpy]

Google is your friend , your 94 is slightly different but same thing , just different location.

Yours should be easy to access by removing the front passengers wheel and its located in the left exhaust manifold.

The wiring connector is up between the battery and washer bottle , you can buy the genuine part which will plug in or by the generic Bosch one and you need to join the wires with the connector that comes in the kit.

[Dimonsta]

Was driving today and the check engine light came on, checked the code and was number 32, the O2 sensor, I guess you were right I'll get that replaced asap and post if it worked.

[Dimonsta]

I changed the O2 sensor and no change what else can it be?!?!

[thorpy]

Done the coils yet?

[Dimonsta]

Nah man, waiting on them to arrive bout them of a member on here paid him and haven't gotten a reply yet. Give me a text on o272o59868

[GT_Head]

Air flow meter?? Try one off a car that you know has a good one if you can.

[Dimonsta]

Tryed the air flow meter. O think I found the problem, unpluged the coils one by one and one didn't make a difference so I'm assuming its that.

[Dimonsta]

I replaced all the coils, a couple seemed cracked. The car goes better now and the stutter seems to be gone, but it seems that it still doesnt wanna boost properly, what else could it be?

[Dimonsta]

Was just fiddling with the hoses to see if any were ripped or had holes and I noticed that the turbo gauge was connected to the vacuum before the Nov, so I connected the Nov directly to the vacuum on the intake manifold and took it for a boost, it had immensely more power but it now seems to not want to boost properly in 3rd gear and above, but the power difference is immensely more powerful. Should I check all the other vacuum hoses? To see if any are blocked?