rough idle???

[nshannon]

91 240 hatch, redtop sr20dethas front mount, walbrol 255 (stock fpr), safc2, apexi boost controlerstock block, everything else is stock the car runs rough under 3k rpm, when boost is applied the car runs goodwhen the #1 cyl coil is pulled (wile running) the car continues to run rough (dosnt change), pulled #2 cyl coil wile running ran worseswapped #1 and #2 coil, same situationfresh plugs, all are good except #1 (dry black carbon buildup)injector clicks when 12volts is applied directlycould anyone point me in the right direction? oh and the injectors are getting voltage + sparkplug sparks when pulled and shorted out
Modified by nshannon at 4:04 PM 6/5/2009

[GODCHSR]

Was the gap on #1 correct?

My initial thought was injector #1 is bad but I changed my mind...I may sound off of my rocker here but I'd check the compression on the #1 cylinder.?.?.?

[nshannon]

yes i set the fresh plugs gap to 30pulled fuel rail to check injectors, when pump primed fuel rail #1 was leakin so new z32 injector on #1 + z32 fuel filter, now it wont start at all attempted to set timing by turning crank pulley to 2nd notch from left, pulling CAS and lining up notch with yellow dot dosnt even try to fire

[GODCHSR]

IS it getting any fuel at all?

Check to make sure the filter is in the proper direction.

[Bongpain]

IS it getting any fuel at all?

Check to make sure the filter is in the proper direction.

or mistakenly flip-flop the fuel feed and the fuel return line.

[biggjerryc]

sounds like an injector is bad to me. I had this same problem on my ka. it was the injector

[nshannon]

today i did a compression test, #1 held 100 psi 2,3,4 held 145-150 i looked at filter + lines, its rightremoved fuel rail with injectors still installed (#1 is new+not leaking) cycled the motor and all four are a squirtin pulled #1 coil, with plug shorted out on block it fires my plugs are no longer being fouled out, all four stay clean and smell of fresh fuelfell confident everything is there with the exception of timingwile attempting to crank it sounds close to firingrepeated timing process several times and tried tweaking CAS with no resultDoes anyone know if the method im using to set my timing will work or am i required to remove the valve cover to line up the dots on the cam sprockets, EXE.PLEASE HELP ME, I NEED BOOST. SOON.

[liquid_cool]

well...the #1. cylinder fails compretion test's man..thats an issue there...but you have alot going on with the turbo set up..its not standard timing...you say you have a safcii correct?..are the base maps working..is there a safe mode for it?..does it controll injector pulse?..the point im getting at..and this is not one area im good in..is that your supposed to have +fuel per LBS of boost..if your safC is saying your under load..it may be holding the injectors open too long and running you rich..that would leave the fresh smell of gas on the plugs...there is another option with timing..with a turbo..its my understanding..you retard the timing..you need to know how much of a retard you need for your setup...you should however check your timing at TDC (top dead center) anyways to make shure...get back to us with what ya find with the timing and we can narrow it down from there.

[nshannon]

the car originally ran great until a week ago when i started experiencing hard starts and rough idle im confident my original problem was a bad oring on the #1 injectorthe fuel maps on the safc are conservative tunes but i didnt set it up so not 100% on thathow much compresion should i have, can i run 100psi for a wile?

[liquid_cool]

155 is the norm for a comp test man..if your at 100..sumpin is up..and thats 155 min to 200+ish at times.

[Bongpain]

well with #1 at 100psi you should still get the vehicle to star. and my motor test at 145-150 psi also and still running great at 12psi stock internals. i did have the same problem when i first drop in the sr. timing was off. just bite the bullet and remove that valve cover and check your timing before you wash out you cylinder wall. sound like the same problem i had. (bad timing)

[nshannon]

replaced coolant temp sensor and tried setting timing yesterday and on the first attempt it cranked right up like everything was coolidle is still not right with a repetitive, small, but deep hickup no torque at low rpm but again runs good past 3.5 kpretty sure timing still needs adjustment but it runs and you are right, the best way to do so includes pulling the valve cover

ps, i feel ur bongpain

[lazerusthedonutking]

i agree with that gdchsr guy, it sounds like a compression issue, it runs good when the boost is on. more compression with boost. so i'd check your head gasket, spark plug gaps and consider new piston rings. the boost might be enough to over power a compression leak, but it's only gonna get worse, especially with the turbo constantly pushing on it. quick fixes never turn out well, do it right or don't and run into more problems that could have been avoided with proper repairs. guys who take the easy way out drive mustangs, remember that

[nshannon]

you sir are wise and i agree with you totally looks like im going to learn how to build an SR a little sooner than i anticipated

[nshannon]

i have removed the safc so im on the stock fuel map and replaced fpr, its adjusted for 36 psi at idle, new plugs gaped to 30the timming has been set to 15* btdc with a timming light on spark plug wire between coil and plug#1 cyl holds 120 psi all others 150 psi or soruns pretty good once warm, much better than before but requires throttle + patience on cold motor and begins to hickup if left to idle