Identifying my 4agte problem

[reecegze]

Hey guys recently i have been having problems with my 4agte.. When the car comes on boost 10psi it starts to splutter and choke every gear thru the high boost rev range... I tried lowering the boost to standard 5-6psi and it does it sometimes only 1st 2nd gear.. The turbo has fair bit of shaft play where u can hear turbine hit the sides of the housing on idle revinng , it was slowly getting worse and worse but up untill now it used to boost fine and ran sweet.. I am heading towards the turbo being rooted and causing these problems but what else could it possibly be ???ive got New sparkies, new leads, new fuel pump , cleaned injectors, timing is sweet , afm is plugged in, exhaust is free flowing. Anything else i should look at ??

Cheers Reece

[skin]

Afm?

Sounds like your running stock ecu on a big port motor?

Might be too much boost for a stock ecu, but yea turbo dosen't sound good lol

[reecegze]

Yer its an 4agze afm dli.. Also i get this loud sound around the turbo area whilst driving sounds like something is arching or the turbo is hitting the housing something bad .. Only happens every now and then.. The ecu can handle up to 12psi from what i read and its ran 10psi solidly for 1 year now..What else you guys rekon ?? Does it sound like symptons of turbo failure ??? As like i said it still boost fine to 6psi then after that car starts to choke on accelleration.

[jono]

any smoke? could the turbo be so far gone that its blowing oil through?

[fixeruperer]

so on 6psi can you rev the engine thru to redline ?
if the turbo fins are hitting the housing it would probably be a good idea to replace the turbo

[reecegze]

Yes in every gear except for 1st when caining it ... 2nd 3rd are all ok to redline..

With 10psi it would do it every gear when it starts to go on past 6psi

Turbo is not blowing any smoke as yet

so on 6psi can you rev the engine thru to redline ?

[fixeruperer]

i dont think a turbo prob would cuase a splutter effect more of a lagy one
but the turbo is rooted so replace it and work from there.

[reecegze]

ill be changing the turbo next week , its just doing my head in that this other problem is happing whilst boosting

[Sam_Q]

I think you should stop driving it immediately, I think the shavings off the turbo housing would be going into your engine

[YLD-16L]

Afm?

Sounds like your running stock ecu on a big port motor?

Might be too much boost for a stock ecu, but yea turbo dosen't sound good lol

I ran stock ECU and AFM on a big port with a turbo setup at 15psi with no probs.

The turbo needs replacing, simple as that.

As for the issue you're asking about:

It'll be a fuel or spark issue, run an O2 meter in the exhaust and ensure it's not leaning out causing the hesitation. Also check your plug gaps and make sure it's not blowing the spark out as that'll feel like you're hitting a rev limiter.

The spark with the stock coils is fine for a lot more boost than you're running if it's all set up correctly.

[Cuzzo]

It seems like your having nothing but problems reece....

whats doing....

[-GT-]

Yeah i'd stop driving it on 10psi asap, especially 'caining it to redline' - as YLD said, sounds like fuel or spark. Not excessive boost so stock setup should be fine, said you've got new plugs and leads, so what about fuel filter and pump? If it's fine on lower boost but struggles as soon as you turn it up, sounds like it's not able to cope with the increased fuel demands.

Which means caining it is going to blow it apart, soon.

[reecegze]

i replaced the pump when i thought it was my fuel pump doing it ..So its got a brand new main fuel pump and fuel filter was changed 5 months ago when i did the surge tank setup.. It could be the sparkies doing the problem.. Ill change the turbo and ill go from there.. But it sounds like what your saying yld-16l

[reecegze]

Cars... it was good for 1 year after the conversion

It seems like your having nothing but problems reece....

whats doing....

[Rallystanza]

Check your spark gap, if it is still at 1.0mm, get it down to 0.8mm.

You need to check your fuel pressure too I think. Can you fit a fuel gauge?

Just a couple of thoughts. Good luck