AFC

Just install MegaSquirt or some other system that allows you to tune your car, or just have a question about tuning and the options available? Feel free to ask it here.
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infil
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AFC

Post by infil » Sat Jul 07, 2007 9:26 pm

Thought this would be worth posting hehe.

Today, one of our customers came in with a stupid rich condition constantly being set, this car, 04 srt, has a fair ammt of work done, should easily be in the 12's, but cant break the tires loose out of first gear. We've sorted out alot of the wiring issues with it previously, and got around to the afc. Pulled the afc out after making no headway with it today, took the car for a drive and had the tires breaking loose in the middle of 4th with no problems. There is still a WOT problem, its breakin up real bad at about 15psi then smooths out again, but we're pretty sure we have that nailed, just need the parts to get here. At about 70% throttle the car is hazing the tires through the first 3 and breaks em loose as soon as it hits boost in 4th.

This just solidifies my opinion of the afc. The afc when installed was tuned on a dyno, and the only effect it had was causing multiple rich codes, a handfull of map and a few tps codes.

I did not install it, however according to the diagrams i could find, it was hooked up properly.
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NinjaneonTurtle
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Post by NinjaneonTurtle » Sun Jul 08, 2007 4:06 am

Yeah, AFC's and turbo cars with MAP sensors are a no no. Its good for N/A on our cars, that's about it. Although we've been sucessful on my buddy's fully bolted and cammed Spec V. Installed the neo, then did some butt-dyno tuning. We're installing the A/F gauge tomorrow then fine tuning it some more before we can take it to the dyno. Still can't hang with the SRT-4 though :twisted:
1998 Neon R/T Coupe
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infil
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Post by infil » Sun Jul 08, 2007 8:55 am

i've found that afc's' work well on a few jap cars, and thats about it for descent gains. Overall, still not a fan hehe, thats a good chunk of the cost of a good piggy back(utec, aem etc) which is more work, but also aLOT more power.
Infil <--click
AMSOIL, Technical Auto Group, S.I. J&V Tools
Fast Times Performance 2002 Subaru WRX 2.5, 11.936@113.18
95 All Motor Neon
13.958@96.99
SOHC - ALL MOTOR - STOCK BLOCK

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1fast2liter
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Post by 1fast2liter » Sun Jul 08, 2007 1:26 pm

i took mine off in favor of the megasquirt.
Image

96 blue coupe sold
96 white 4 door sold
95 blue sport parted out
97 straberrie red coupe sold
95 black base parted out

current drivers
97 dodge ram 1500 5.9 ext cab sport fire engine red. tinted windows cat back exhaust suer chips tune, 1 mephis audio sub

90 audi 80. 400 miles to the tank
2002 custom sportster 90 whp and quick too

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NinjaneonTurtle
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Post by NinjaneonTurtle » Sun Jul 08, 2007 4:13 pm

yeah I've heard MS is really the only way to go.. but what about tuning SRT-4's?? hrmmm, guys have AFC's on those, I imagine it would work because it has a more than one bar map sensor. either way I could be wrong.
1998 Neon R/T Coupe
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infil
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Post by infil » Sun Jul 08, 2007 6:32 pm

i just pulled this one off of an srt4 hehe. with the afc, which was dyno tuned by ripp mods, which is probably part of the problem, car would run into a wall at 15psi.

It still hiccups at 15psi/wot, but part throttle it'll pull up to 22 w/o a problem, and keep anyone in the car pinned to the seat heh.

Part of the problem is the wiring that was hacked up at the pcm connectors. There was around 6" of exposed wiring on the map signal, tps signal and a handfull of others had sections soldered into em and left open. He has some other issues the dealer is taking care of under wty then its coming back to me to get the wiring sorted out at the pcm, and a fwe other goodies done.
Infil <--click
AMSOIL, Technical Auto Group, S.I. J&V Tools
Fast Times Performance 2002 Subaru WRX 2.5, 11.936@113.18
95 All Motor Neon
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SOHC - ALL MOTOR - STOCK BLOCK

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Post by NinjaneonTurtle » Sun Jul 08, 2007 11:26 pm

so maybe its just a bad wiring issue with the SRT-4. it has trouble boosting at full throttle, the afc's going off of throttle position, and well airflow.. but neons don't measure flow.. they measure pressure, that might be the issue? unless you wire up an airflow sensor just so the AFC can read it and clamp the map sensor. if that'd work anyway. but does the srt-4 have it clamped in the first place is what I'm wondering.
1998 Neon R/T Coupe
1988 Colt Hatchback

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infil
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Post by infil » Mon Jul 09, 2007 1:55 am

this car has a few wiring issues, we solved 90% of em when the AFC came out. Handfull of em have been solved, but a few are being done under factory warranty. He bought the car pretty heavily modified so dealer kinda stuck themselves with it as he sees' fit to take it to them. So far they havent argued much, but this time its getting a little deeper hehe.

My guess from scoping otu the MAP and TPS is a combination of really poorly done wiring repairs down at the c3 connector on the pcm, probably the worst wiring job i've seen done installing the afc, both of which left alot of exposed wiring at c2 and c3, the 2 were shorting together. The TPS has been replaced once, along with the pigtail, the MAP is next. It has a stage2 pcm in it, but looking at the map readings on the scanner and on the scope, their all over the place.
As i said, the dealer is dealing with the wiring at the PCM, if they give him any crap though he's going to have me do it. Hed rather put money into mods than repairs and I cant say i blame him honestly. That is not a quick job to repair as the damage to the harness is pretty extensive and where the wires were cut for the tps, im going to be replacing pins in the connectors to repair em.
Infil <--click
AMSOIL, Technical Auto Group, S.I. J&V Tools
Fast Times Performance 2002 Subaru WRX 2.5, 11.936@113.18
95 All Motor Neon
13.958@96.99
SOHC - ALL MOTOR - STOCK BLOCK

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Post by NinjaneonTurtle » Mon Jul 09, 2007 5:47 pm

woah.. hacked to shit huh.. well at least do it right if the dealer doesn't. maybe after all is said and done are you going to put the AFC back on?
1998 Neon R/T Coupe
1988 Colt Hatchback

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