Running Lean
06-28-2003, 10:03 PM
#1
1st Gear Member
Thread Starter
Join Date: Jun 2003
Location: United States
Posts: 89
Running Lean
I have a '95 GT and have upgraded to a cold air intake, 80mm MAF, 65mm throttle body, adj. fuel regulator (42psi), 1 5/8" unequal shorty headers, prochamber h-pipe, and digital air/fuel gauge. Only now the check engine light comes on time to time. Gauge reads .14 steady acceleration, .98 after letting off, then down to .03 after coasting for a bit. I don't see any vacuum lines off and have changed the O2 sensors and PVC valve. Has anyone else had this problem from these kind of upgrades?
07-04-2003, 01:06 AM
#3
1st Gear Member
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Join Date: Jun 2003
Location: United States
Posts: 89
Running Lean
When the light first came on I had stock MAF cal. for 19#injectors (now it's 80mm w/ stock electronics). The place where I got the gauge says it should be .3 to .7 volts at idle(closer to 1.0 volt you get the richer it is) and from .7 to .9 at WOT. I was thinking of trying to clean the wires, then switch back to K&N induction kit, and then new O2 if the other attempts fail. The codes were lean mixture left and right banks...and SPOUT circuit grounded.<edited><editID>95stang</editID><editDate>37805.9635300926</editDate></edited>
07-07-2003, 04:49 AM
#5
2nd Gear Member
Join Date: Jun 2003
Location: United States
Posts: 439
Running Lean
ahh you may be right there is some tweeking i have heard of the maf . when u start getting that kind of stuff . it obviously changes the intake track , i dont know how the bend goes but twisting the maf acordingly should give you better readings . i forgot the logic behind this but obviously the air moves at diff speeds on the short side of the turn than the longer one . i heard this on a tweecer board . he had to adjust his maf curve due to a cold air ontake . to make it short he had to tweek it a lil i think at the 10 o clock position . his car did breath better but he was wondering why he had to go and adjust the maf curve . example xxx of voltage i xxx of kg an hour of air . i wound up that the new intake track he had created skewed the maf reading thats all . sound like this may be your case ??? not that its bad just your maf did know what was goin on thats all . leme know
07-15-2003, 11:09 PM
#6
1st Gear Member
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Join Date: Jun 2003
Location: United States
Posts: 89
Running Lean
I ended up trying all kinds of different combos on my CAI.Anyway I tried switching my stock electronics from the MAF to the MAF electronics from a 98 Cobra that I had. When I did this the car ran the best it had in a long time. So I got to looking at both sets of electronics. Come to find out the 95 sensor had a lot of gunk on it (probably from the K&N oil) so I cleaned it off with heavy duty brake cleaner. It worked...light doesn't come on and fuel pressure is down to 36-38psi and the A/F gauge reads as it should.
