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-   -   tune is very inconsistent could big injectors be the problem? (https://www.homemadeturbo.com/engine-management-10/tune-very-inconsistent-could-big-injectors-problem-84728/)

ifly87 10-07-2007 10:12 PM

tune is very inconsistent could big injectors be the problem?
 
I can drive the car one day and the afr's will be great 14.7:1/vac and 11.5:1/boost and the next day it will ilde rich and be rich in boost, or another day and it will be lean to the point where the car struggles to idle, even though it never leans out past 11.5:1 in boost. My fuel economy is horrible about 20mpg, if I get the computer on it and fix it it will just be off the next day. the temps arent changing much and I always take the data when the coolant is warm (180f). its a Z6, I was contemplating using E85 so I went with precision 1000cc injectors they are low impedance so I am running a resistor box. I was told on PGMFI to mess with the injector offset but I dont know which colum to adjust or wich way or how much of an incriment I need to adjust it by and I dont want to do any dammage. ever since installing these injectors even if the afr's are perfect it idles rougher than it has with the 450's in.

bitchasscracker 10-07-2007 10:23 PM

Re: tune is very inconsistent could big injectors be the problem?
 
hmm i've heard of this problems using afc's but never with a chipped ecu

ifly87 10-07-2007 10:38 PM

Re: tune is very inconsistent could big injectors be the problem?
 
Yeah i've been messing with the tune for about 2 weeks and if I make it right one day the next day its off again. Well I found some info on it on xenocron's crome writeup,

bitchasscracker 10-07-2007 11:29 PM

Re: tune is very inconsistent could big injectors be the problem?
 
what is your intake air temp ??

brettsb16a2 10-08-2007 08:23 AM

Re: tune is very inconsistent could big injectors be the problem?
 
Mine was doing that too, then it got real bad and ended causeing a misfire. It was only on cylinder 3. At first i thought i lost a spark plug wire or plug, so i did the easiest thing and swaped wire first then the plug and still no fix (note the 3plug was black and the others were fine, that should have been my indication of a rich condition and not a spark condition). Then i grabbed the injector wire and shook it allittle and the idle went back to normal. I noticed a bad connection, i thought it was a bad solder at my inline resistors, but still had the problem, i had overlooked the crap used dsm connector. The terminal was just barely to wide. The loose condition caused a super rich condition on that cylinder) I squeezed them together and fixed it and my AFR have been pretty dang constant now. Before it actually made a misfire, my afr were just not constant, i just thought that was the best it will get with an AFC. I was wrong, it got better but afc's still stink.

ifly87 10-08-2007 09:43 AM

Re: tune is very inconsistent could big injectors be the problem?
 
My IAT is usually right around 110-115 if I'm in boost and if I'm just cruising down the highway it drops to like 100 or so it all depends on the day of course but I try and keep an eye on it and it stays pretty consistant.


Originally Posted by brettsb16a2
Mine was doing that too, then it got real bad and ended causeing a misfire. It was only on cylinder 3. At first i thought i lost a spark plug wire or plug, so i did the easiest thing and swaped wire first then the plug and still no fix (note the 3plug was black and the others were fine, that should have been my indication of a rich condition and not a spark condition). Then i grabbed the injector wire and shook it allittle and the idle went back to normal. I noticed a bad connection, i thought it was a bad solder at my inline resistors, but still had the problem, i had overlooked the crap used dsm connector. The terminal was just barely to wide. The loose condition caused a super rich condition on that cylinder) I squeezed them together and fixed it and my AFR have been pretty dang constant now. Before it actually made a misfire, my afr were just not constant, i just thought that was the best it will get with an AFC. I was wrong, it got better but afc's still stink.

I was wondering if this could be my problem because it does seem to be getting worse, when I let off the throttle between shifts it doesnt sound like it used to almolst like its still getting some gas, I had to cut a tab out of the injector's where the plug fits in they looked exactly like the dsm's, I'mm gonna try and bend the tabs a little to make sure its getting a good connection. I pull the plugs and they all look pretty close but thats after idling for awhile. When I first start the car and drive it misfires for half a mile down the road or so and I get quite a bit of blueish smoke, but I'm not using a drop of oil or coolant, once it warms up it doesnt misfire at all.

bitchasscracker 10-08-2007 03:07 PM

Re: tune is very inconsistent could big injectors be the problem?
 
jesus 115* ---- mine never goes above 100 but i got a fan on mine

ifly87 10-08-2007 03:34 PM

Re: tune is very inconsistent could big injectors be the problem?
 
you have a fan on you're intercooler?? where are you're charge temps measuring from the stock sensor on the back of the IM?

whatupdohc 10-09-2007 02:41 AM

Re: tune is very inconsistent could big injectors be the problem?
 
the fan is there a write up if not u should do it. do you use a geo rad fan or what?

bitchasscracker 10-10-2007 05:26 PM

Re: tune is very inconsistent could big injectors be the problem?
 
no i bought a indoor outdoor temp sensor at walmart for $6 and drilled my intake and put the sensor in there. my intake temp is usually within 5*-10* of what the temp is outside. the fan that is on there is off a cbr600 i think its small i got one on the intake side of the cooler and one on my radiator. both of them together dosent even pull what the stock honda one does


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