The backfire thing is probably caused by an exhaust leak at or near the manifolds or crossover pipe. Until you are able to get a good CO reading it is hard to say about the idle. More than likely there is a vacuum leak you haven't located yet - maybe the vacuum advance shut off valve is still off allowing the spark to stay advanced, maybe the manual idle screw is open, maybe the seals at the intake tubes just after the butterflies are leaking. It sounds like you are close but need to be very methodical and absolutely sure of each application function and check now. You might start a checklist and go back over everything to be sure you haven't overlooked something. Harold McElraft - 3354 --- In dmcnews@xxxxxxxxxxxxxxx, "painterdave72" <painterdave72@xxxx> wrote: > > > Hey all please give me some insight to this freaking problem.. My car still does not > idle smoothly... or rather the engine vibrates at idle..I ahve just installed all new fuel > injectors and the car runs and accelerates excellently... I have done a > commpression test on the cylinders and they all have great pressure.. I have tested > the fuel pressure and it is within parameters and holds pressure fine.. Where i have > the c02 screw set now is alittle richer from wehre the car dies when u lean it out.. > that is why i think it shudders at idle,, but if i make it any richer the car does the > annoying backfire thing out the exhaust.. its now excatly backfireing though its just > like when u drift down a hill on a motorcyle with straight pipes and let off the gas the > rumbleing in the exhaust.. i do have a free flow exhaust on my car with no cat > convertor just straight headers to the muffler.. some mechanics i have talked to > seem to think it is a result of the exhaust but some people such as John Hervey > think it is still not right.. I dont think the engine should vibrate at idle either.. cause > when u give it some gas it stops right away..if i do richen it up till the frequency > valve shuts off it idles much better but is way to rich and does the thing in the > muffler.. i am so tired of messing with this.. the car runs greatly except for this.. i do > have a rebuilt warm up regulator also.. and every other sensor on the motor is new > say for the actual fuel dist and the accumulator.. and the idle speed motor.. Any > help?? please?? Thanks..Dave..Vin.. 15275... To address comments privately to the moderating team, please address: moderators@xxxxxxxxxxx For more info on the list, tech articles, cars for sale see www.dmcnews.com To search the archives or view files, log in at http://groups.yahoo.com/group/dmcnews Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/dmcnews/ <*> To unsubscribe from this group, send an email to: dmcnews-unsubscribe@xxxxxxxxxxxxxxx <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/