R33 Engine Issues

[SXY]

hey ive got a r33 rb25det cold starts its hard to start sometime 2 or 3 time to get her to kick over,

and when under load and coming on boost only 7-8psi back fires n pops

ive pulled the plugs out they were pretty fowled up as looks like it running rich cleaned them put them back in as there fairly new. cleaned the throttle body n butterfly, but still happens

any1 had simular problems?

any ideas?

been told cold be

crank angle senser

fuel pump

spark plugs

or coil packs?

donty really want to replace all of them just guessing what the problem is?

PLEASE HELP!!

thanks guys

Edited May 19, 2009 by SXY

[ELMOHASA33]

hey mate to me it dosnt sound like it would be coil packs or spark plugs more likly the fuel pump or air flow meter where do you live?

do you know some one that can check the diognostic codes in your ecu?

[Chrisrotary]

Is it just hard to crank? ie cranks slowly then fires or you get a "tick" every time you try but nothing much else. Keep in mind in 33s the battery is in the boot far from the starter. original or a jap battery maybe well past its use by date by now and also its a damn cold day in melb and cold batteries will allways struggle. get a free check at the autobarns or k-mart.

bad miss fire under boost (technically ignition break down) is generally caused by one or more faulty coils. plugs are a pretty basic device and dont often cause failures. If you can accurately re-gap the spark plug to smaller setting do that try .8mm instead of stock 1.1mm. this will make the coils job easier and should temperarly reduce ignition breakdown.

Were all plugs fouled? If so i would geuss module. remember if you have wet plugs you are unlikely to decent igniiton; dry plugs and not running right is lack of fuel or no fuel.

hope this helps or steers you in a direction.

I am a mechanic with limited diagnosis experience. i have had a bit to with imports and and this just rule of thumb stuff.

[SXY]

hey im in campbeltown area,

i just put new plugs in regapped to .8 but then it idled like crap revs would go up and down, so put them back to 1.1, new plugs made it go a lil better but still pops and shit on boost,

definatly over fueling, plugs were fouled up again when i pulled them out this time, so i dont think it will be fuel pump now. tapped the coil packs made no difference,

might try anfd get some new or second hand coil packs try that next

still hard to start on cold start after all this as well, definalty not the battery checked that still around 13 volts

Edited May 23, 2009 by SXY

[Kinks]

if it's running rich i would suspect an air leak in your piping

[ELMOHASA33]

i realy dont think its the coils as they cuase a miss when faulty not a back fire your on the right track when you say its running rich back fires are caused when engine is to lean or to rich or the timming is out its most likly an air leak your air flow meter or fuel pump

[SXY]

ok ive now put a 040 fuel pump in, changed the fuel filter found ther was a split hose replaces that fuel line that was split, starts 1st time every time now.

but still have the problem as it comes on boost 3 to 3.5 thousand rpm it cuts out like the whole engine then starts back up and goes hard again, but still back fire now like every gear change

rrrr so fustrating any1 reccomend some where i can take it im over tryin to fix it now, decent workshop that wont rip me off

Edited June 13, 2009 by SXY