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PollyMobiles Rebuild

found a small leak where the rad top pipe meets the thermostat cover usually cos i didn't sand smooth the metal pipe surface. fixed now.

with a cold engine i let the wideband heatup first till its reading and then start the engine and i noticed the cold cranking afr begins very rich like 9afr and stumbles around 400rpm and then 10secs later the revs and mixture slowly builds to 800rpm and 14.7afr so maybe the cold cranking setting is too rich and causing it to flood?
 
is that with the cold start high rev bypassed? mine seems to do that and its really unhappy for like 20 secs and levels out at 1100 till its warm and this is with the cold start bypassed! although i reckon its the sensor richening it up
 
think its one of the cold start parameters in the nistune map thats abit off cos when i run the janspeed system remap the high rev cold start and idle up when using PAS all works fine. need to learn more bout nistune program n try copy those parameters over
 
is that with the cold start high rev bypassed? mine seems to do that and its really unhappy for like 20 secs and levels out at 1100 till its warm and this is with the cold start bypassed! although i reckon its the sensor richening it up

Have ya checked ur IAV is clean moving freely n configured?
 
It is clean but no way of configuring it as i dont have that software and no money for it at the mo if you looked and the thread running problems continued it says pretty much everything lol! When are you next in london?
 
mine was running rich on coldstart when i removed my 2nd coolant sensor after fitting the QG injectors paul, its never failed to start but it hunted like mad and would,nt kick into closed loop for a couple of miles.
so i,ve since refitted it, and it is now closed looping within 1/2 a mile
 
I thought you made various trips down here sorry im probs going to end up with a nee tb at this rate if im honest its getting rediculous

Hope u sort it soon mate
 
I thought you made various trips down here sorry im probs going to end up with a nee tb at this rate if im honest its getting rediculous

Hope u sort it soon mate
 
hmm having a look at the turbo remap that ed did, the crank enrichment map is richer than the janspeed, original turbo & stock map. also the idle region of the fuel map when its warmed up & revs lower to 700rpm, ed really richened up the mix towards 9-10's afr for some reason i forgot bout. as its in closed loop during idle maybe the nistune is trying to richen towards 9afr but the ecu self learning tries to pull it back to 14afr and occasionally over-does it and goes wayy lean and revs drop, then i re-learns after a min, richens up to 14afr to rev back up.

when i open datascan and click Clear Self Learn it goes from 14.7 richens back to 9.5-10afr as it says in nistune.

i'll play with idle mixture n stuff over weekend
 
If it falls within the idle and the nistune is saying richen up, then i can see how the two would be fighting each other. Not sure why you'd be that rich that low down though, as surely you're never gonna see boost at 700rpm at next to zero throttle.

But obviously i've never played with \ seen the nistune so cant say otherwise :)
 
argh this nistune is really peeing me off. afr all over the place. sometimes too rich sometimes too lean n stalls. at idle the janspeed & stock map is more stable when using PAS or select a gear in that the revs automatically pickup whenever theres more load. so i tried copying that region of the map into the turbo map along with all other parameters and it doesn't work like some other unaccessible parameter i cant see. adjusting the idle screw also really messes up the entire afr.
trying to get afr as close possible to the map but it still goes lean n hunts n tries to stall when braking and turning.
dunno what i'm doin, so many things to tweak. anyone nearby know how to use nistune?
 
O2 seems to work. Tis varying up n down. Changed to another sensor and same thing. Dunno what the heck this ecu's doin. Now its runnin 9-10 afr idling, next min it learns and goes up to 15 and occasionally leans to 20 to stall. The timing gauge also reads 7 deg at idle when the map says 20 but when i touch the throttle it jumps up to what its suppose to be. if i put any load like selecting gears or reverse, use Pas or pump the brake or all three especially, it stalls.
 
nope no air leaks. all pipes connected and boost gauge showing good vac.
i want to up the idle timing from 7 to 15deg cos when i goto datascan and click adjust idle which forces it to run 15deg it idles little faster and richens up, as though 7deg is way too late.
but i dunno how cos changing the timing map has no effect, that only affects the on throttle timing, so something is taking over during idle and the self learning occasionally messes things up
 
i got an idea. when i upload the janspeed map it automatically idles up when using PAS but when i copy over the exact same values on to the turbo maps fuelmap (idle bit), ign map, rpm enrichment, etc it doesn't idle up.
so if that feature is like hidden in the janspeed map from the menus then maybe i could load up the janspeed map and manually copy all the turbo map values into it and see if that works.
 
Nope no effect. Gauges show that the iav opens 60% when it goes lean and 100% when its really lean and about to stall. When it learns after few secs the iav slowly closes and afr also slowly goes back to 14.7
 
So with the janspeed map installed everything runs as it should / as it was?...seems an odd one. And everything that was on the other engine has been installed on this one, e.g injectors, spark plugs etc.

Its gotta be something simple.

Wish i could say where to look, maybe follow franks suggestion and give baguete a shout. :)
 
hmm good news i think i found the culprit. looks like the MAF translation is the cause.

first i uploaded the janspeed map, engine runs fine, idle up working, IAV keeping a low 20%, timing round 15deg.
then i copied the turbo map over bit by bit, one parameter at a time, except for the idle region of the fuel & ign map. all running ok.
until i copied over the maf translation, then the revs & ign timing drops and mixture leans and all unstable. using pas makes it worse.
copied the janspeed MAF back on and its fine again.

test drive showed the mixture & rpms are stable and correct at low - med rev cruising. little rich at high load going 10afr rather than the mapped 11afr.
tried a rough mixture of the two maf maps, janspeed maf during idling revs and turbo maf beyond and is roughly gettin there. heavy flatspot when setting off at lights round 2k rpm where i merged the two maf maps together so will need fine tuning.

this is prob a butch way to fix this issue but tis what i know works at the mo.
 
just having a clear up of the garage mess.
found me stock calipers, a rear caliper, pulsar discs, stock rear discs and front discs. prob gonna bin em cos no one'll prob want em

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bit roomier now
 
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Good news on finding the problem! have no clue about mapping all confuses me! still good thing you found the reason why.
as for the calipers etc. why not put them in the sell section you'd be surprised how many people have a sticky caliper. lol
 
the calipers haven't been used for over a year, i'll have to take em apart n see they're ok before sellin.

discs are in the bin cos they're cheap enough to get new anyway.

i've uploaded a smoother blended maf map and it runs much smoother now. bit of a botch solution cos in one hand running at idle the closed-loop learns and runs 14.7 but above idle-med rev its too rich for few secs. cruise at mid-high rev for awhile and it relearns to go back to 14.7 then when i slow down to idle its too rich and so on etc. when accelerating hard its 1afr too rich comparing to the map.

it's less likely to stall at idle now, even when i put it in reverse, heater fan on max, use PAS and pump the brake quickly, it just goes abit lean at 17afr and keeps running.

plugs are golden yellowy

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cylinders nice n dry and oil level hasn't moved abit

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garghhh i just about had it with this nistune mapping, so confusing all these issues. idling and cruising is fine as the o2 sensor finds 14.7 in closed loop but everywhere else the mixture is too lean and can't match the mapping afr. especially at full pull the mix actually rises dangerously from 12afr at bout 3k towards 14afr at 6k and i back off. i tried going back to the turbo maf map, increase inj latency, multiplier, adjust the idle screw, nothing.
the mixture above idle used to be fine till i messed with the idle screw and maf map, can't get it back now.
almost considering i have to go back to Ed to properly sort it ALL out for another £150+ (maybe leave out the dyno cos most the fuel/ign is tuned) and taking out summore holidays sacrificing some days for the UK & nurburgring road trip.
feel pretty clueless and just wasting £££ fuel here
 
puzzling, i took the motorway to work tday mostly above 3k beyond closed loop and the mix seems to behave themselves. WOT it goes to 10.3 and stays put. keeping n eye on it
 
ok since the map is almost sorted i think i'll take the forged engine apart

removed outside bits

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cover off

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HG looks fine. i like this type of gasket as it doesn't fall apart

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close up

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valve heads have a heavy build up of prob burnt oil

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View attachment 26961

underside of HG intact

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easier to clean block surface

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sump & timing cover off

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crank off

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shiny

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wipe this lip of crud from cyl 1-4 before pushing the pistons out

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pistons 1-4. no signs of excess blowby

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position of the ring gaps prob move about during operation. haynes shows it should relatively be
top ring: 12 o'clock, 2nd ring: 6 o'clock, top oil ring: 12 o'clock, bottom oil ring: 9 o'clock
basically facing opposite of each other.

the rings on the forged pistons were (o'clock):
piston 1: 12, 4, 5, 8
piston 2: 12, 2, 12, 3
piston 3: 12, 1, 11, 2
piston 4: 11, 12, 1, 5

generally the gaps are quite close to each other which won't be good for controlling blowby

honing marks on cyl 1-4. seems deep doesn't it?
summore views. light vertical marks from the compression & power strokes

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checking ring gaps tomorrow
 
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prob let a machine shop do it for me, give better consistant finish than by hand.

looking under the pistons there's only 6 small drain holes for the oil rings, dunno if they're enough to clear excess oil from the rings compared to the massive drains slots on a stock piston. will take pics
 
prob let a machine shop do it for me, give better consistant finish than by hand.

looking under the pistons there's only 6 small drain holes for the oil rings, dunno if they're enough to clear excess oil from the rings compared to the massive drains slots on a stock piston. will take pics

i think a machineshop will say they will have to hone about 5 thou out to get the correct finish paul fwn you may have to start again with another block, else your ring gaps will be too big
 
start over? seems radical, not buying another block. actually maybe the spare stock engine that came with the turbo kit could be machined.
 
removed rings from piston 1

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heres the oil ring expander

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top ring has no markings but 2nd ring says N150

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i slid the rings into cyl 1 using the piston and measured the end gap which is so time consuming. how do ppl get em back out cos i tried to slowly pull em out from both sides but feel the sharp edges wanna scrape in.
haynes says the max gaps are
top: 0.3mm, 2nd: 0.45mm, oil rings: 1mm

piston 1 reads
top: 0.432mm, 2nd: 0.356mm, oil rings: 0.5 & 0.533mm

heres the 3 tiny oil ring drain holes

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this one feeds the wrist pin

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drain holes and piston markings

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cleaned piston head with scotch pad & wd40

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rings on. tis bout as much work as i can withstand tday

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good work very busy paul! so it could be a mix of the #### poor honing and the bad positioning of the rings then? thats a shame! just get a block and then get it done properly maybe? you can have my old 1ltr block for nothing if you want mate
 
u sure? that'd be ace and saves the spare turbo engine :)
am i correct in that the 1L & 1.3L blocks are exactly the same, just the pistons, rod & crank that's different?

i'm not certain that's the cause but looks like it. I'll put it together properly and put aside for now. then its a case of: when this current engine blows up i fit the turbo engine, when the turbo engine blows i fit the reassembled forged engine. if the forged engine still burns oil i remachine the 1L block, swap over pistons with new rings and start from scratch.
 
u sure? that'd be ace and saves the spare turbo engine :)
am i correct in that the 1L & 1.3L blocks are exactly the same, just the pistons, rod & crank that's different?

i'm not certain that's the cause but looks like it. I'll put it together properly and put aside for now. then its a case of: when this current engine blows up i fit the turbo engine, when the turbo engine blows i fit the reassembled forged engine. if the forged engine still burns oil i remachine the 1L block, swap over pistons with new rings and start from scratch.

they,re only slightly different paul (mine,s a 1.0 block with cga3 crank and rods eh)
and i guarantee its just the honing thats causing the oil consumption
 
So using the forged piston with 1.3 rod & crank on the 1L block may not work?

Wonder if my local machiners has a way of measuring the hone to confirm. I prev saw on youtube some engine builders who uses this optical device that measures the roughness of the honing.. Or was that paint smoothness?
 
So using the forged piston with 1.3 rod & crank on the 1L block may not work?

Wonder if my local machiners has a way of measuring the hone to confirm. I prev saw on youtube some engine builders who uses this optical device that measures the roughness of the honing.. Or was that paint smoothness?

no, just the outer castings are slightly different paul, and all the internals are interchangeable.
take the block to a local engine builder for a 2nd opinion, (but i think he,ll say "what did they use ? f/kin 40 grit stones!)
 
measured the piston & bores incase a rebore & new rings are needed.

bore is bout 71.43mm
piston head 70.6mm
mid section 71.2mm
piston skirt 71.4mm
wrist pin side of piston is 70.75mm
top ring is 1mm thick and 2nd ring is 1.2mm thick

looking at JE website for pro seal rings dunno if its 71mm or 72mm bore rings i should get.

http://www.jepistons.com/Products/XC7100.aspx

$22 for a ring set? thats really cheap ain't it?
 
measured the piston & bores incase a rebore & new rings are needed.

bore is bout 71.43mm
piston head 70.6mm
mid section 71.2mm
piston skirt 71.4mm
wrist pin side of piston is 70.75mm
top ring is 1mm thick and 2nd ring is 1.2mm thick

looking at JE website for pro seal rings dunno if its 71mm or 72mm bore rings i should get.

http://www.jepistons.com/Products/XC7100.aspx

$22 for a ring set? thats really cheap ain't it?

we had to file those ring-gaps to suit iirc paul, so they would have been the 72mm ones eh.
and far cheaper than oem eh :eek:
 
the gaps seem abit tapered, outer gap is narrower than the inner. prob due to the oversize as you say.

aye unbelievably cheap as chips compared to nissans £100 deal :eek:

would ya say tis best to get new rings since they're cheap, have machiners finely hone the block and i end up bedding the engine in once again? or can these rings be reused on a rehoned block?
 
the gaps seem abit tapered, outer gap is narrower than the inner. prob due to the oversize as you say.

aye unbelievably cheap as chips compared to nissans £100 deal :eek:

would ya say tis best to get new rings since they're cheap, have machiners finely hone the block and i end up bedding the engine in once again? or can these rings be reused on a rehoned block?

i guess that is per piston eh paul, but still cheap, and you could get the block rehoned and gap some more 72mm rings, or else lightly hone another lowmiler block and re-gap those rings eh
 
£50 a full set is not bad. though customs would prob like to have a big chunk of that too coming from the US

rehone this block and re-gap some new 72mm rings, that's the master plan :)

is it ok to hold off the block Will till i need it?
 
yeah its done something like 65k and can still see the original honing marks so that must be a bonus! and i can hold onto it fine its sitting in my garden with my damaged head sat on top to protect it covered nicely,,, just the odd cobweb around the clutch i noticed lol.... but its ally so all should be fine!

all i want is the pistons
 
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