VU v6 manual missing?

[Percy0654]

Don't know exactly how well the video will go. My most irritating issue here is the noise at the tailpipe. I have spent a few weeks and $$ chasing this down and am fast running out of ideas.
New parts:
Plugs
Leads
LIM gasket and all gaskets before it (blown out around cylinders 4 and 6)
Exhaust gaskets (weren't any there or sign of ever being there)
Oil, filter and coolant
Ribbed idler pulley as it was making a horrid noise
Battery terminals as the factory +'ve one broke

Replaced parts off another motor I have:
IAC
TPS
Injectors and o-rings
Fuel pressure reg
Coil packs and module
EGR

Valve cover gaskets were leaking, i've sealed them with some loctite till i can get out and get new gaskets
Cleaned MAF
I have checked relays all seem fine
Repaired the wiring at the coolant temp sensor as it was stuffed

Compression test results
1 - 155psi
2 - 155psi
3 - 157psi
4 - 152psi
5 - 155psi
6 - 155psi

Cooling system was flushed both radiator and block seperately.

Only code i've seen is 0012 which as far as i can find is all normal.

I think that's it. Anyone have any idea why it'd sound like this? Can feel the vibration when stopped at lights and idle is noticeably down on gauge, done this in diag mode to get rough figures idle was at about 750 before all this now goes between 750 and 850. 850 when cold just started, sits at around 800 just sitting at lights. drops to 700 if you use the throttle to hold it at 900 and release it and then slowly comes up to 750.

when driving, otherwise it's unnoticeable. even being in neutral and slowly braking towards lights it seems to hold the right idle until the car is at a complete stop.

I'm going mad trying to find this so any help at all would be appreciated.

Thanks in advance

Tom

 

[dirty hands]

seems ok at the engine

collapsed baffel in muffler or cat converter ?

 

[Percy0654]

I've been dreading that idea hence why I haven't done the cat, would they cause low idle though? and if so is there a way to just check like unbolting them and starting it see what happens?

 

[Bowen]

Iac stepper motor n tps would b my guess second hand = no good just get genuine new u can get it for like $30 combined.... Just remmebr to set the iac to length before install!

 

[Percy0654]

That's just it, even if they were a problem, which I'm pretty sure even the original ones aren't at the moment, there would most likely be a difference between them. There are no noises from either and both move in and out quite well. The port for it has been cleaned aswell. Mostly tried the second hand one just to try and rule the original one out, most of the parts of put in have made absolutely no difference. Only changes to be seen were from cleaning the upper intake and lower intake. I messed with the IAC before I did that. As for setting to length, i'm sure I read on here that you can set it to whatever length you like the computer will change it anyway hence why there would be no point trying to set it to adjust the idle up

 

[Bowen]

I thought the same thing once when this happened to me turned out even the brand new one was faulty, wether or not it was the iac or tps I bought them as a pair.... Yeah it's very contradictory but my manual does say set it to 25.4mm but then also says it's all self adjusting but anyways I just do it anyways as that's what my Haynes manual says....

You checked for vac leaks, fuel pressure, and changed fuel filter etc? If u like u can take off the csc hose for the fpr and smell it if it smells fuel then the diaphragm is ruptured..... And if you get a can of carby cleaner and spray all over the vacuum hoses and the idle changes momentarily then you know u have a problem!

 

[Bowen]

Vac hose* auto correct lol

 

[Nut Kracker]

Changing the IAC is just not a matter of removing the old one and then just chucking in a new one.
Certain procedures must be adhered to, as explained below.
Take particular attention to the Note in 3.12.

 

[Percy0654]

Pressure reg is fine now, old one was stuffed and the new old one is fine did that test on it after a day or 2 with it in and it's fine. Don't have any carby cleaner at the moment but will look into it, if there's something else i can use let me know, don't have heaps at the moment i've used a lot of stuff cleaning **** up. I'm not thinking it's a fuel pressure problem but will change the fuel filter when i do the valve covers just because it probably does need doing. if it was a pump problem i'd be inclined to think it would show itself more than just at idle. Correct me if i'm wrong in any assumptions, as i'm more used to diesel systems and you can really tell when they're starving for fuel for whatever reason.

 

[Percy0654]

Ok, for turning it off is that off off or just back to acc cause i have tried that and no change with either IAC.