Rb20 Running Like A Pig!

[ITFEL]

hey guys just thought i would post up on here some issues i am having with a rb20 i have in a cefiro..... will try to keep it short....

basically i am having some issues with how its running and its really screwing with my head..... it is basically just a drift car.... my fuel pump packed it in so put in a new one.... but have had major problems with it since!!!! it is a bastard to start.... it turns over and gets the feeling like it will start and then wont for ages then all of a sudden will fire up..... it will sit there and idle fine for ages!!!

i then went to back it out of the shed and thats wen this crap started.... it runs sweet at idle..... but bring the revs up and it farts and carries on and shit and cuts out.... but starts again easy enough..... thing is just free rev (ie not under load or driving) it will idle fine then cough and splutter till about 2600rpm then will run fine again and ya can rev it right up till limiter if u like....

so took it out of shed and then ya go to drive it and it coughs for a bit then once revs are up a bit it will drive around all fine... comes onto boost etc

to try get rid of the misfire and carrying on we put new plugs, in changed fuel filter, changed over the afm, checked all plugs and all sorts.... my thoughts are maybe a coil pack is fooked?? (we checked spark on all the spark plugs while they out of the motor by turning it over with the plugs connected and spark is strong) the thing is it idles fine and runs fine once it gets over its coughing issues... so surely if a coil pack is fooked it just would be missing the whole time yeah??

the afm we cleaned out put back on and it still did it.... so took off the afm from my other rb powered car that runs all sweet and made no difference so pretty much cancelled out afm??

its definitely gettin fuel.... took off the line and fuel is flowing out wen ya turn it on..... thought maybe a clogged injector?? didnt check that because a mission to get down to them but all cylinders are gettin wet (fairly easy to see wen ya take the plugs out etc... dunno if this is a definite yes or no injectors are fine)

so this is where we have got to and now stuck.... checked fuel, checked spark, checked afm.... i'm lost..... fuel and spark is basically wat makes a motor run haha and it does run but very roughly for a part of its low down rev range

i have thought maybe a vacuum line cracked?? or a cooler pipe somewhere?? but i had a quick look (by this time i was very over it and didnt want anything to do with it hahaha) nothing seems out of place....

it drove fine and had its last track day got it off the trailer back at home and the fuel pump started packing it in.... then died (it started running real rough and carrying on and the pump was up and down and making bad noises then it just wouldnt start at all, pump wouldnt even prime itself... pretty much a give away the pump is dead to me haha).... then have had these issues since the new pump has gone in.... surely in my theory that the new pump in it should have fired up and ran fine.... but no....

any help?? anything i mite have missed?? anything to look for?? any help would be awesome!!! its not like a crazy modified motor... faily stock aside from cooler and an exhaust..... i dont get how it can be fine pre pump propblems and then fooked and running like a pig now it has a new pump....

cheers

dave

[DVS JEZ]

Glad u kept it short. I read the 1st paragraph. Check the lines arent back to front. Also check that its wired up in the right direction.

Try swapping fuel lines 1st.

[ITFEL]

yeah i tried keeping it short but the more info i guess maybe it cancels out some of the obvious that i tried fixing already.... but will try the fuel lines cheers

[ITFEL]

i got out and played with it again today.... switched the fuel lines around and i reckon i had them right..... it was a mission to start it but..... i found some codes that mite flash up with the ecu and checked that for anything but it says all good and no codes flashed up....

i have another question.... i got the car pretty much as is..... engine wise i havent touched it aside from servicing etc.... i was just wondering and i wondered first up when i got it as to why but it ran all fine so thought it must be ike it for a reason....

it has a z32 afm in it but not in the usual place i would suspect.... its not on like usually see them after the filter before turbo.... it is up top on the cooler piping before the air flows into the throttle body... it has that standard right angled pipe and its just before that pipe where the afm is.... does this seem right??? i thought it must be like that for a reason?? but ould thi have something to do with my problems?? few mates that have looked around the engine bay has pointed out its a weird setup but it works i guess.... why is it like that?? or is it a f**k up on whoever did the intercooler setups behalf and i should change it??

cheers

Edited January 4, 2011 by ITFEL

[Guilt-Toy]

1: remove fuel pump. check to make sure its installed correctly - sitting inside the tank correctly. if not sure take pictures and post it up.

2: wire a direct 12v feed to the fuel pump using a relay. if you are unsure how to do this then search.

check back with results

[Rekin]

i got out and played with it again today.... switched the fuel lines around and i reckon i had them right..... it was a mission to start it but..... i found some codes that mite flash up with the ecu and checked that for anything but it says all good and no codes flashed up....

i have another question.... i got the car pretty much as is..... engine wise i havent touched it aside from servicing etc.... i was just wondering and i wondered first up when i got it as to why but it ran all fine so thought it must be ike it for a reason....

it has a z32 afm in it but not in the usual place i would suspect.... its not on like usually see them after the filter before turbo.... it is up top on the cooler piping before the air flows into the throttle body... it has that standard right angled pipe and its just before that pipe where the afm is.... does this seem right??? i thought it must be like that for a reason?? but ould thi have something to do with my problems?? few mates that have looked around the engine bay has pointed out its a weird setup but it works i guess.... why is it like that?? or is it a f**k up on whoever did the intercooler setups behalf and i should change it??

cheers

That afm setup i believe is what the VL boys do so they have flutter.

Check out this guide, engine bay pic looks identical to what you described? http://www.calaisturbo.com.au/showthread.php?t=111492

[ITFEL]

ahhh ok so its been done like that to make a noise?? i dont really care about the noise thing.... is the afm setup like that going to negatively affect how the motor runs at all??

[Plan-FAILURE]

Check these...

Fuel Pump Relay

02 Sensor

Ignitor (on top of rocker cover, closest to firewall)

Battery (mine ran like a piece of shit when the battery was on its way out - will be more likely to be this if you have a decent sound system)

If your pump doesn't even prime, it's probably your fuel pump relay because this gives power to the pump.

When an O2 sensor dies it usually prevents the car from starting/idling but can be intermittently faulty.

If the ignitor is on its way out you will find the car splutters and hesitates all over the shop It will also run like a piece of shit with flat spots and surges throught the rev range.

James

Edited January 6, 2011 by plan-b

[Psymon]

o2 Sensor shouldn't stop the car from starting/idling at all. I drove with mine unplugged for a month and barely noticed the difference besides fuel consumption.

[ITFEL]

cheers guys.... will try changing out the ignitor i guess.... i thought o2 sensor but like above wrote wen was messing around with shit on it once i forgot to screw in the sensor once and it still ran....

i been trying different shit on it as i think of things.... i had a thought maybe the fpr is stuffed?? could a spring inside or watever makes it work be fooked?? my reasoning is it idles fine.... but try increase the revs and its all over the shop.... could it be as the vacuum does its thing etc instead of smoothly going up in revs its just opening and dumping fuel in straight away and runs like its being choked and then once ya burn it off it will run fine??? (hence the idle fine.... fart and carry on then it burns off the initial fuel dump to run fine once it gets the excess fuel burnt off??? ie. idle then shit till about 2500rpm then fine) it makes sense in theory to me but i'm not even really sure thats how fpr's work??? i'm just guessing

[Justlikemusic]

did u fix it?

[DVS JEZ]

Is it blowing black smoke when it pops and carries on?

[toffy]

it does it cold and hot? , maybe the fuel pump hadn't shat itself , maybe it was something else?? . water temp sensor??