misfire since adding 3" intake pipe

[blackers10]

hey guys
i was wondering if anybody else is experienceing a misfire (not terribly bad one tho).. after they have installed a 3" steel intake pipe??
im thinking its because it sits directly ontop of the leads as they pass over the rocker cover to the rear 3 cylinders??

any ideas to stop it happening??
thanks guys

[BLACKAUXR8]

not sure about the 6 cyl but my XR8 has a sensor in the middle of the intake pipe. I made my intake pipe and siliconed it in. If the 6 cyl has it in the same place it might just be a loose connection?

[FGII-XR6]

there is no sensor in the intake of the I6 the lead theory sounds a good place to start.

[ratter]

put new leads on the car and as added precaution wrap them in some tubing to stop them failing prematurley

[MRJUCY]

Is it well sealed at both ends? Any leaks can cause bad readings & cause it to run rough.

[blackers10]

its well sealed MrJucy so dont think its that

regarding new leads.
is it better to get thicker ones to help prevent this occuring or??

[GK]

If you wanted to test whether it's the leads reacting to the metal intake piping, could you wrap the piping with cloth temporarily to insulate, ie test?

GK

[blackers10]

i could give that a go GK
sombody told me alfoil wrapped around the leads to insulate would possibly help also??

thanks guys

[The Monty]

Originally Posted by blackers10

hey guys
i was wondering if anybody else is experienceing a misfire (not terribly bad one tho).. after they have installed a 3" steel intake pipe??
im thinking its because it sits directly ontop of the leads as they pass over the rocker cover to the rear 3 cylinders??

any ideas to stop it happening??
thanks guys

Dude, have you cleaned the pod yet?

[blackers10]

no i havnt cleaned the pod
BUT its had the miss if i remember correctly only since i added the 3" pipe
and i had the pipe going into my standard airbox with the K&N panel filter.. so i dont think its the pod being dirty

[JC]

Originally Posted by blackers10

hey guys
i was wondering if anybody else is experienceing a misfire (not terribly bad one tho).. after they have installed a 3" steel intake pipe??
im thinking its because it sits directly ontop of the leads as they pass over the rocker cover to the rear 3 cylinders??

any ideas to stop it happening??
thanks guys

Run the car at night, in the dark with the bonnet open, and see if the leads are arcing to the intake pipe. If so, then you certainly need to insulate them with something. Some split heater hose will do the job nicely.

[jjj]

Use the 3inch throttle body pipe of an EL falcon intake. Then run the alloy intake pipe from that. Most dyno runs I have seen using this elbow with a 3in alloy pipe, seem to get good results. They are actually going for a good price on EBAY now and are one of the first things to go at the wreckers.

Cheers

[Eu-GenixX]

did you have to disconnect any vacuum lines when you installed the new pipe?.. could be a lose vacuum line somewhere ... that can cause the car to run rough and with a misfire type feel... does it go away if you give it a good rev?

[The Monty]

Clean your pod and see how it goes. It could just be dirty, they are meant to be clean.

[Eu-GenixX]

haha.. how dirty is this pod?

[JC]

Originally Posted by The Monty

Clean your pod and see how it goes. It could just be dirty, they are meant to be clean.

If you read properly, it was doing it before the pod as well.

[The Monty]

I did read it properly, but it seems you did not. It was not missing when the pod was on with the original intake, but when he added the three inch intake, it started missing.
Its just it might have got a little clogged up in between, I know I left mine for about 15000 k's (they say clean it every 50000, stuff that), my car was doughy, and starting to miss, cleaned the filter, and it was heaps better, it was just full of crap, as up here is dusty, as we are in a drought, and it clogs them up pretty quick.
Id still clean it Brenden, you might be supprised, I know you said it wasnt doing it before, but just give it a try.

[blackers10]

yeah ill give the pod a clean see if she idles a bit smoother
im gonna do the throttle body clean etc too

as if you give the throttle a quick stab it sorta hesitates

is there any reccomended ways to clean a K&N pod filter??
because in the instructions it says wash it with their degreaser stuff then rinse it clean.. then let it dry... but how long should you leave it for before its dry?

eh ill figure it out

cheers guys

[JC]

Originally Posted by blackers10

yeah ill give the pod a clean see if she idles a bit smoother
im gonna do the throttle body clean etc too

as if you give the throttle a quick stab it sorta hesitates

is there any reccomended ways to clean a K&N pod filter??
because in the instructions it says wash it with their degreaser stuff then rinse it clean.. then let it dry... but how long should you leave it for before its dry?

eh ill figure it out

cheers guys

As long as it's mostly dry (say a few hours in the sun), it should be OK to re-oil and put back on. If you look at the K&N site, it actually says that the filters work best when dirty. I'm not sure if that applies to non-K&N pods etc, but I imagine it would.

Have you got a picture of the pipe from airbox area to TB? I would be interested to see what's hooked up where - are you sure the breather hose from the back of the motor is plugged into the air intake? If not, it will cause the car to have a slight miss as it's drawing air straight into the motor and/or intake, where it is supposed to be sealed.

[blackers10]

all relevant pipes etc are hooked up so no leaks anywhere

the breather hose goes down along the injector area then up to the front of the pipe (where it comes from the TB)

[waggaclint]

it wont be the filter..a dirty air filter wont make you car miss fire....its probably leads or ya knocked vacuum hose of somewere when fitting it...take the pipe off and see if it runs ok with no intake on it....it should run fine hey (just heaps of induction noise).....check the resistance of ya leads you can do it on the car pretty easy....

[Stav]

It is highly likely the leads .They get squashed by the poorly designed metal intake pipes .I am yet to see a good one yet.They hold alot of heat,suck in hot airand squash the leads.In saying that..for drags they do provided more air than the standard "boston strangler" style intake.

[SIKSIX]

I noticed when i installed my 3'' pipe the it made it idle a touch lower/rough going by feel not tacho, and also seamed like it was running a bit richer.

Also is this in D or N, also try and bring the revs up 100-200 rpm and see if it still does it.

[blackers10]

ive asked a few people.. gave it a t/b clean... cleaned the pod.. and they say it feels fine..
next step is probably the o2 sensor as it is on its way out

[StealthAu]

Just give it a clean with T/B cleaner.

[blackers10]

i just said i did that..

ill be lookin at new leads and a new o2 sensor and see what happens after those

[GK]

Originally Posted by Stav

"boston strangler" style intake.

Boston strangler - classic Stav! LOL!

Originally Posted by blackers10

i just said i did that..

ill be lookin at new leads and a new o2 sensor and see what happens after those

So you've cleaned the tb and pod. The idle should be better then!

If it's still doing it, the backfire I mean? Have you done JC's suggested night test to see if the leads are arcing anywhere? Have you tried wrapping the leads with something to insulate them? I'd certainly be trying these things before going down the route of leads and O2 sensor. If not, you may be throwing money out the window.

Remember this problem only occured AFTER you fitted the metal intake piping.

GK

[StealthAu]

Originally Posted by blackers10

i just said i did that..

ill be lookin at new leads and a new o2 sensor and see what happens after those

Sorry mate, my post was a bit vague. I ment give the O2 sensor a clean with T/B cleaner.

[JC]

The O2 sensor doesn't affect cold start or idle. If it's worse when it's warm, then I'd suspect O2 sensor, but if it's worse when cold, I'd suspect leaking spark (ie arcing somewhere).

[ratter]

Originally Posted by JC

The O2 sensor doesn't affect cold start or idle. If it's worse when it's warm, then I'd suspect O2 sensor, but if it's worse when cold, I'd suspect leaking spark (ie arcing somewhere).

Which is what he got told over a week ago