AngryRB

Ive replaced the TPS but the coolant sensor snapped off and half of its stuck in the head still, unbelieveable place to have a sensor, can't get a spanner on it cause of the way it sits. Havnt got round to the Fuel reg yet, all these sensors are eating my $$$ up, and its been running without any black smoke or stalling for about 500km's now, so for now just waiting and see. The engine seems to have constant tappet noise and recently noticed some noise that occurs under load hot and cold, its sounds like in the cylinders, probably the start of piston slap , took the oil cap off while it was running and seems to be a bit of blow by, wondering if the blow by return (which ive blocked) could have been messing with the map sensor which sits close to it. funny how since I blocked the blow by return and fuel vapour return it hasn't missed a beat.

So will next replace Coolant sensor, TPS and fuel regulator and see how it goes. If still playing up will consider an exorcist or lighting it up and pushing it off a mountain.. lol Some pics for those interested, These are the Map sensors, the orange Map sensor is from my other Dedicated LPG ute ( Genuine ford, made in Germany), the blackish one from the tickford ( made in Italy), not convinced the tickford one is faulty but swapped it anyway,

I couldn't get any volts or resistence with my tester but autoelectrician said on his tester it was showing response to the throttle, ive bought a new TPS just incase its playing games on me, It does seem to happen at right at that cruise spot where the throttle is hardly open.

This sounds spot on, the fuel pump does keep running when its switched over to LPG, when I took the manifold off to put some new injectors I found some large pools of liquid too, was still there after a few days sitting so not sure if it was fuel. When It would start playing up was after cruising for a while and coming to a stop at traffic lights, then after flogging it for a few minutes it calmed down a bit but still rough. Im going to get a new reg to rule this out and see how it goes. The last few days its behaved itself, ive got 15L/100kms on petrol and 17L/100kms from LPG, so its come down a bit and ive blocked the vacuum lines near the Map sensor which are the blow by return and fuel vapour lines.

+1 to this, would rather an RB any day

Update- ran good today for about 30mins then pulled up at traffic lights and it had a big fit, big clouds of black smoke puffing out, had to pump the throttle just to get it to move. Dropped into autoelectrician who hooked up his scan tool, and no fault codes come up, TPS is working, leads tested and good, managed to get it home with it filling the street with black smoke, pulled into driveway and its idling smooth again, when I have it in neutral and increase the revs slowly its smooth til 2000rpm where it bogs down and misses badly, at 3000rpm its really trying hard not to go further. Anyone have any more suggestions, note on both LPG and Petrol it does this, for some reason it pours the fuel in but there's no fault codes..

In the Gregory's manual it says to check for voltage, I assume this is what you mean, I checked today and found the wires to the sensor give the 5volts so computer ok, the actual sensor is not giving me any voltage. Not sure if I'm doing it properly or the sensor is rooted, while connected the manual says to back probe the middle wire which I take it means slice into it and place a probe on there and ground the other probe of multi-meter??? if so then the TPS is dead, interestingly I can start the car with it disconnected and seems to idle fine. I swapped my other falcons TPS over and tested that too and it gives the same zero voltage reaction to the throttle, whats the chances of 2 dud sensors in a row. hmm The last drive of 20mins has been smooth, the car is definitely better with the replaced cat, has a lot of low down torque but will have to see if she's still using the 20L/100kms.

replaced the MAP sensor and O2 sensor today, also reset the battery then took it for a drive and it drove perfectly, but then half hour later went to drive it and it was like a pig, on partial throttle it would cut out on me, I had to pump the throttle to keep it going, seems to settle enough to drive it but super sensitive just dropping it in D. Took it to exhaust shop and got CAT and Resonator replaced ( cat was collapsed), for the first few Km's it was jolting and playing up then just started running sweet again so I don't know if shes fixed yet or not. Have a new symptom which has appeared, that is when im cruising alone at 2000rpm and engine braking, it will all of a sudden drop down a gear violently like if you'd given it the beans, and also as you are slowing down it drops the low gears in as if it was manual box , I think the car is possessed.. Items replaced so far are -Coilpack, plugs -Injectors -MAP sensor - 02 sensor - cleaned fuel rail -CAT and resonator - cleaned IAC - Sprayed manifold with carby cleaner and no reactions ALSO- car has dual fuel and the problems happen on BOTH LPG and on 98unleaded next is coolant sensor and Throttle position sensor and have the gearbox checked..

+1 for exhaust leak, Id be expecting a few broken studs in the head and a warped exhaust manifold face, maybe some shaft play in turbo too. could also be some noisey pulley bearings and belts

tomorrow Im gonna take it to exhaust shop and have the cat and front muffler replaced with a straight thru pipe, then replace the coolant temp sensor, 02 and map sensor with the other falcons that runs perfect.. thanks for the help so far ..

I have a second shitbox falcon same model so I can try swapping sensors but a few mechanics said if theres no engine warning lights on then the sensors should be fine would a blocked cat cause rich fuel mixture?

Have a Au XR6 falcon ute and trying to figure out whats doing with it. Its using like 22L/100km and can actually see it puff out black smoke when free reving it. It runs ok with an intermittent roughness like its trying to stall on me and a few times has cut out completely on me while driving, usually as I come to a stop at a traffic lights it will get rought and the revs come down to 400-500rpm. 90% of the time she'll run perfect though. This weekend I removed the manifold and found the intake manifold flooded with what looks like fuel, so ive installed new injectors and tightened all intake manifold bolts and resealed the plenum. Took it for a drive and still doing the intermittent wanting to stall and coughing black smoke, no engine warning lights on and will idle perfect most of the time. so got me stumped. Have read the falcon forums and I think people on here might have more knowledge. Just looking for sensible idea's, suggestions and not smart ass comments. Apart from this issue its a good vehicle, dual fuel and just got a paint job.

Looking to sell my Series 2 Head with Tomei Cams in perfect condition, only selling cause I need a NEO head for the 25/30 build. Looking for $700, Cams have had very little use ( cost me over $800 alone) and engine has always had 170psi each cylinder so its a good head and cam package. Note- parts still on car so give me a few days to dismantle once sold.... stock exhaust from turbo to exhaust tip $100 Stock Turbo in VGC - $300 includes some lines and intake pipe Stock S2 AFM- $ 80 Stock wheels with tyres $350 ( 2 have brand new tyres) Stock injectors in rail $150 All negotiable within reason, all in perfect condition parts located in south Brisbane, 0466 257 118 or private message thanks

what about this http://www.atpturbo.com/mm5/merchant.mvc?Screen=PROD&Store_Code=tp&Product_Code=ATP-VEVO-008&Category_Code=VEVO plus this http://www.atpturbo.com/mm5/merchant.mvc?Screen=PROD&Store_Code=tp&Product_Code=ATP-VEVO-102&Category_Code=VEVO use the adaptor to link the evo turbo to the t3 manifold

yep, $4k to go backwards over a stocky with a GTX3076, the simple combo worked best, that twin scroll manifold was a lot bigger than the stocky manifold, I think it slowed down the gases a lot and cancelled out the twin scroll effects if there were any.

I hope your not disappointed, I wasted $$$ on my twin scroll low mount setup and couldn't have just dropped a RB30 in for the win, Can only get so much response from a small motor, just saying.

why mess around with twin scrolls, just drop some cubes and a decent turbo in there!

Sounds like it could work, but ive decided to keep things simple and get a stock rb30 and marry it to a neo head, its a long term project and failure will be more likely if i start pulling things apart or trusting machine shops to do stuff right. Stocker RB30 and conservative boost should see happy days. If there's anyone interested in a good non neo head with fresh tomei 256cams let me know.

I used a 3inch xforce rear oval muffler for 320 easy kw's, doesn't look as nice as your one though. Can take a pic of the insides to compare if you want.

found a cool video on youtube for modding the skyline

What would be minimum compression result on the comp guage if looking at a running rb30? im guessing over 150psi would be a thumbs up? Probably have to buy the whole wreck/car unless you are awesome with tools and have a car hoist handy?

ok so sounds like my easiest cheapest option is to sell my non neo head for a neo head and bolt it down on a decent stock 3L or aim for 350+ and get some forgies, seems overkill to get forgies for the low 300's, especially being a streeter. how would a stock neo head compare to my non neo head with 256 tomei poncams for flow etc, will there be any difference/restriction upto the 340kw? KiwiRS4T- Im probably just a bit OCD, I like to start the engine stone cold and hear it quiet apart from the injectors ticking, plus the forgies mean a rebore which ill might be stuffed up by machine shop and leave me with mega piston slap, superben- I don't know what the clearance would be, just planning stage at the moment

Mine has a 3 1/2inch system with one 3inch Xforce oval muffler on the back, doesn't drone just sound like its breathing alot, have a dyno clip if interested.

is there a certain pressure/torque that will break the rings/ring landings on a stock piston or does the piston fatigue over time? just wondering because my rb25 dropped cyl 5 and wasn't knocking at all, I am thinking it was a sudden boost spike to 25psi from the usual 20psi, so in the case of new pistons/rings in an rb30 can I expect a ring landing to break or should it be fine at the same power level 320-340kw (gt3076). KiwiRS4T- only problem with forged is the cold start slap, apart from that id not think twice.

I have roughly calculated that the head would need 2mm shaved off to bring it up to 9.5ish to 1, less with decking the block and a thin head gasket. I would go the neo head but I have newish tomei 256 cams in my head and it seems to be in great condition, would a neo head be comparable to mine seeing as I already have the tomei's? on a side note, I recently asked an engine rebuilder about a stock rebuild and was told the cast pistons are not available for a rb25/30 build and I should go forged, is there any truth to that or were they trying to make more money from me?