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Post Service Loss Of Power?

nsanity

By nsanity,
in Engines & Forced Induction

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nsanity Rising Star

nsanity

Posted
Posted

Hey guys,

I just had an 80,000km service done on the line, as well as having the exhaust manifold gasket done and the car feels like its lost a lot of power, throughout the whole rev range..

I have it running on 0.80 Bar (i think thats what the AVCR measures in), however it simply will not push over 0.61 since the service.

The car is also extremely quiet, exhaust note wise - however i put that down to me being used to the mild exhaust leak, although it might be quieter than when i bought it.

Service guide followed was the 80,000km one listed in the Gen Maintenance forum

Iridium plugs -> NGK Platinum

Castrol Edge oil still.

Turbo Gasket, Exhaust Manifold gasket + 3 studs.

I have a PFC, which i put the hand controller in tomorrow, what things should i be looking for (besides knock).

Would the 80k service include removing any advance (forgive me if this is electronic, i'm used to old holdens) that may have been set by guys who originally tuned it (ice down in melbourne)?

The workshop did a great job, but they don't specialise skylines so i'm trying to give them a heads up if anything thats a quick fix, or risky.

Cheers,

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rev210 Grand Master

rev210

Posted
Posted

check the timing. Perhaps ask them if they adjusted anything at including the timing.

There is a remote possibillity that an exhaust gasket (any of the ones put in) was out of alignment when bolted down, the factory ports aren't well matched for a start. Do some looking about 'after' checking the obvious timing and plug gaps.

Irridiums are a waste of money by the way. Go the copper plugs. NGK 6BCPR6ES etc..

nsanity Rising Star

nsanity

Posted
  • Author
Posted (edited)
Check that the vacuum lines are hooked up correctly.

Is this in regards to the Boost Controller?

I have an Apexi AVCR. Now its maxing at about 0.6 kg/cm2 which i think roughly works out at 7psi (or stock), the AVCR is still reading what the boost is (i assume), is it possible that its not doing its thing with the wastegate (forgive me, i'm not sure exactly how it works).

what would i look for to see that this isn't the problem?

I've chatted with Marc this morning, but unfortunately didn't grab my PFC Hand Controller (~5 hours sleep last night, late shifts) to check anything there - But the guys who worked on it, mentioned that Vacuum Hoses hooked back up and that the Gaskets fit very flush (both Marc and the mechanic were surprised about this).

I reiterate that the car isn't misfiring, and in general power delivery is smooth, just not anywhere near as oomphy as it was.

Thanks for the help so far,

Edited by nsanity
BHDave Grand Master

BHDave

Posted
Posted
Is this in regards to the Boost Controller?

Nope, all of them. You will have the signal for the boost controller, the hoses between the solenoid and the actuator, the hoses to the bov, the hoses to the charcoal canister. There are lots of them.

Some one who is not familiar with what goes where may get something backwards accidentally.

It's just a thought. Timing may have something to do with it aswell as has been mentioned.

nsanity Rising Star

nsanity

Posted
  • Author
Posted
Is it surging in the higher rev range( 5000-7000rpm)?

Timing can be an issue.

Raz

forgive me, explain surging?

The car simply Plataeu's in performance (it has a very stockish feel to it - not that i ever drove one, to break traction off the line, you have to dump it at 4-5k, rather than simply just plant your foot in first) at around 3-4000rpm.

doesn't feel like its being starved (i've driven cars where the fuel pump isn't up to the job, doesn't feel anything like that) - Boost hits 5 on the Dash (0.6 on the AVCR) and simply just hard lines there.

If i can have stuff to take to them on wednesday when i settle the account, hopefully its just something quick.

I thought timing would be all electronic? i didn't give them the PFC hand controller, nor do they have the equipment otherwise.

zebra Grand Master

zebra

Posted
Posted

almost sounds like an exhaust restriction.

when you say it plateaus does it go hard up untill a certain point then taper off or is it flat all the way through the rev range?

before i found out some prick at an exhaust shop had welded a bit of box section steel (bout and 1" square) in the tail pipe of the rx7 the car would pull really hard till about 5-5500rpm then would die in the ass. once i had it removed the car would rev to 9000 easily.

im using this as an example by the way not as a plug for rotaries :happy:

nsanity Rising Star

nsanity

Posted
  • Author
Posted (edited)
almost sounds like an exhaust restriction.

when you say it plateaus does it go hard up untill a certain point then taper off or is it flat all the way through the rev range?

before i found out some prick at an exhaust shop had welded a bit of box section steel (bout and 1" square) in the tail pipe of the rx7 the car would pull really hard till about 5-5500rpm then would die in the ass. once i had it removed the car would rev to 9000 easily.

im using this as an example by the way not as a plug for rotaries :happy:

Think of it as if all of a sudden you couldn't get the throttle more than half-open. I still get to 7k rpm (i change between 6.7-6.9 when driving hard), but the feeling just isn't there.

Thats the feeling of loss.

sidenote - why the f**k would someone weld shit in your exhaust? noise?

Thanks for all the replies, i'll get them to check the vacuum hoses, and the timing on Wednesday.

Edited by nsanity

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