corsa turbo miss firing

[Dirtydog1]

i have a corsa fitted with a 1.6 8v se turbo engine, but it is very hard to start and once started has a constant miss fire from what seems to be at least two cylinders.
it has only just been built, started first time and ran fine at first then it seemed like it ran out of fuel and just died. i topped up the fuel but now it has these symptoms????
it appears to have a spark and the plugs get wet with fuel (new plugs,leads,cap,rotor fitted) it also apears to have compression.

strangest thing is, if you disconnect the injector plugs it starts up and runs nice for about 10 seconds.:confused: i am now very frustrated.

it has fitted an adjustable fuel pressure reg but was running fine with it fitted from the beginning.

any help much appreciated, as im dieing to take it for a drive now!

[Dirtydog1]

ps its not a ****y courtney conversion. all the managment is standard stuff so basically just a 1.6se engine realy i guess. cheers

[let_nova]

is it possibly overfuelling? wet plugs?

[Dirtydog1]

could be, but would that cause a miss fire on just a couple of cylinders? ive swapped the injectors over with a spare set and it was exactly the same?

[Mike]

Bet its blowing the spark out.

[ck]

try gapping plugs to 0.7mm

i'd borrow a compression tester just to be sure the engine is in good health.

could be faulty sensor/air flow meter maybe a bad air leak

[meritlover]

if its struggling to start, its unlikely its boost "blowing the spark out"

it needs to be compression tested, check your rising rate fuel regulator is adjusted/working correctly (if fitted) and take it from there.

[Dirtydog1]

im going to compression test it today, and see what the results are, its just strange that when the injectors are unplugged it fires up and runs for a few seconds.

[craig green]

Bet its blowing the spark out.

At idle?? :roll:

Its probably running on the fuel left in the cylinders, it shouldnt run with the injectors unplugged. Assuming the regulator is plumbed in correctly (return not back to front) you want 3 bar pressure with the vac pipe removed. Its definately waay overfuelling if the plugs are wet fouled.

Was the engine running fine before you added the blower?
Did the ECU, loom & AFM all come from the same source?

I also fail to see the difference between a 'sh!tty Courtenay conversion' & yours if you are running the std management on a std E16SE. Kettles & pots!

[ck]

I also fail to see the difference between a 'sh!tty Courtenay conversion' & yours if you are running the std management on a std E16SE. Kettles & pots!

to be honest its the other way around. id rather have a Sh!tty courtenay conversion than one thats running a std e16se on std management with a turbo attatched.

[Dirtydog1]

courntney manifolds r pants in my opinion is what i meant.

any way that aside, the compressions were all good this morning 12ish bar, i gapped the plugs and adjusted the fuel pressure tinkered with a few other bits n bobs and it fired up and ran really well, i set the timing up roughly so i could take it for a little test.

it went like fook (only went up to 2nd gear and not flat out) on my return to the house i gave it one last blip in 1st and a bit of grey smoke came from the exhaust :( and the engine cut out

sooooooo, tested the compressions again no1 was 12ish 2,3,4 range between 5 and 8 bar. also getting alot of crankcase gasses coming from the breather now.

so im thinking i may just set it alight.

[Dirtydog1]

to be honest its the other way around. id rather have a Sh!tty courtenay conversion than one thats running a std e16se on std management with a turbo attatched.

my mate has a 1.6se running standard gear except for fuel pump and regulator and t3 turbo and it ran a 14.7 1/4 mile if i remember rightly. not bad eh?

[Dirtydog1]

as i dont have fuel pressure gauge, is it possible that the fuel pressure may still be too high and i have washed the bores thus causing loss of compression? or am i clutching straws there? haha, as the conclusion im having now is that either the rings have dis intergrated or the pistons are like swiss cheese?

im getting a lot of gas coming from the breather filter but the engine actually starts but wont idle as the compression is so low.

[meritlover]

tested the compressions again no1 was 12ish 2,3,4 range between 5 and 8 bar. also getting alot of crankcase gasses coming from the breather now.



did you do the compression test with the throttle wide open? as you often see results like yours when the throttles closed as the 1st cylinder takes a gulp of air, and theres nothing for the rest to suck in.

bore wash wouldnt cause such a low reading. try a wet test, with a teaspoon or so of oil down each plucg hole. if the reading increases then its likely its ring/piston/bore wear or damage.

could be a head gasket, but until your sure the compression test is done correctly its hard to say.

[Dirtydog1]

i tried pooring oil into no 2 cylinder as that was the worst reading and the compression did not increase very much at all.
the rings or pistons must be frail as a 90 year old lady if they are to blame as i litterally drove it 500 meters haha, but then i guess if the timing was out etc it could kill them pretty fast?

[Dirtydog1]

poored oil into 2,3,4 cylinders
3 and 4 improved and went to 12 bar
2 went up to 10 bar

i then span the engine over to clear the oil and tried again, 3 and 4 went down to 10bar and 2 went down to 8

removed the head, the head looks good still, the gasket was fine so i can only see it being the frail old piston rings that have died a sad death.

[Dirtydog1]

/\ anyone else share the same opinon?

[craig green]

If the rings/engine is as frail as you say, it's clearly not upto having another 50/100bhp output.

I'd say it looks like rings from your tests.

[Dirtydog1]

If the rings/engine is as frail as you say, it's clearly not upto having another 50/100bhp output.

I'd say it looks like rings from your tests.

once it has new rings fitted it shouldnt be so frail i hope lol
its my own fault realy as i got lazy when building the engine and didnt bother taking the pistons out the block. i just knew it was a runner.:tard:
never mind, just hope it is just the rings and not cracked pistons.
any suggestions as to best place to get rings from?

cheers :thumb: