Just took the car off the Dyno about an hour ago and it's running at 18:1 Air/Fuel Ratio. It pegged the meter as lean as you can get.
The only current mods are the C&L Intake w/ 76mm MAF. The engine was pinging before and after this was put on, so I figured the A/F was lean but this is insane.
I'm getting pulled in 1000 different directions. I've been told to put the stock intake back on and re-dyno it and see if it still pegs (so I know it's not C&L's product.. and I will be doing this most likely). I was advised to get a regulator and just dump more fuel in to cover up the problem. I was told to get a new Engine Management System.
Basically I just need some ideas here.
The equipment was dead-on for other people's vehicles, and mine was the only one running this lean, it was checked in both pipes.
Edit: The CEL is also not coming on at all to indicate any problems.
My stang is pinging too. i have adjusted the timing, but it seems to come back after a while. i dont have an answer to your question, but any info about this topic would be appreciated my myself as well.
My stang is pinging too. i have adjusted the timing, but it seems to come back after a while. i dont have an answer to your question, but any info about this topic would be appreciated my myself as well.
I noticed the pinging after I had gotten it and talked to a few people. I've always run 93 Octane through it and it's at factory 10 Degrees Advance. I was told it might be cause by the 10% Ethanol in the gas in the county I live in (Emissions BS). I filled up a county to the south without emissions gas and it didn't get rid of it but it didn't ping quite as much.
Anyways, I'll be trying a few different things, but any input is greatly appreciated.
95/5.0 Long tube headers, xpipe, flowmasters, with dumps, 9mm plugg wires, msd cap and rotor, 70mm tb, trick flow intake manifold, under drive pullys, smog elim kit. summit coil, subframe connectors, summit double roller timing chain, and a cam not sure what for cam bc it was in the car when i purchesed it!
Are you absolutely sure there are no exhaust leaks? That will give a false air/fuel ratio.
The intake, again assuming there are no leaks, CANNOT cause this but a faulty TB or MAF could.
Start with the basics.
Not 100% positive on the exhaust leak, but the A/F did occasionally drop to 15:1 when it was decelerating on the dyno.
The MAF is brand new, but I'm going to clean it again to make sure there is no oil on it from the air filter. The engine was pinging before and after the MAF was changed.
I checked today with the old intake and it still pings. My next solution was going to be checking the fuel pressure.
I personally am leaning to believe it is running lean and that it's not a faulty reading because the engine is pinging, if it ran 18:1 on the meter and never moved but my engine showed no symptoms I'd be more convinced of an exhaust leak or other problem.
Thanks for the suggestions, I'll be checking the EGR, TB, and Exhaust.
Just an update because I know someone else was wondering about this:
Called all over today to a few places: 2 performance shops here and C&L Performance and talked about what was going on.
Things I was told to check -
O2 Sensors
Intake/Water Temp Sensors
MAF Calibration Tube (C&L Intake MAF)
Air Leakage in Intake track
Fuel Pressure -
Below 32 Psi at Idle = Bad Regulator
Below 40 Psi at wide open = Failing Pump
All fuel lines for leaks
Fuel Injectors for leaks/clogs/O-ring seals
I've been running through and checking what I can. I planned on a new regulator and pump anyways, so I had a date set to get those put in, it's going to be about 650 for parts and labor for the regulator, under-hood pressure guage, and new pump.
I could have it tuned or just throw more fuel at it, but that's not addressing the issue. I pulled the plugs from my last change and they aren't even discolored tan, they are just white, almost new looking and have 50k plus miles on them, so it appears to have been running lean for quite some time.
One temporary solution I did stumble upon is pulling the vacuum tube off the regulator and plugging it to raise the fuel pressure. Not sure if this helped or not and it's a band-aid for a broken leg, so I undid it and put everything back to normal.
After all this is said and done I'll also be having it dyno-tuned and set up for performance with a new Engine Management System. Hopefully I can find this problem soon, fix it, and not have to worry about it ever again.
1995 Mustangs sample tubes are different then all the other years. The correct tube makes a huge difference and would caus eleaning out and also stumbling at idle.
Stock Injectors GT & Cobra .650 Tube (094)
GT 24lb and Cobra 30lb Black Tube (105)
GT 30lb and Cobra 36/38lb Brown Tube (095)
GT 36/38lb and Cobra 42lb Red Tube (103)
1995 Mustangs sample tubes are different then all the other years. The correct tube makes a huge difference and would caus eleaning out and also stumbling at idle.
Stock Injectors GT & Cobra .650 Tube (094)
GT 24lb and Cobra 30lb Black Tube (105)
GT 30lb and Cobra 36/38lb Brown Tube (095)
GT 36/38lb and Cobra 42lb Red Tube (103)
Yea, I checked that about an hour ago, pulled the entire intake apart, checked the tube, and put it back together and made sure everything as as tight as I could get it. It has the .650 tube, no color, and exactly what Lee Bender described it as.
I just installed a C&L 76mm MAF, Elbow and 70mm throttle body. Mine stumbles a bit a idle to. I'm running 98 octane and still find I'm running a little lean as well. I have a fuel pressure reg and gauge which I'm fitting this week and replacing the filter. I'll be interested to know what the outcome is for this.
the simple way to test is to buy the fuel pressure gauge, hook it up to the fuel rail and let it stick out of the hood so you can drive it, and see the gauge at the same time. then just drive it hard till it pings. watch the gauge if your not getting 39 psi of fuel after you here it ping, and it drops into the 20 psi range you need a stronger fuel pump.
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DSS 331 stroker, AFR 185 heads, Performer rpm 2 intake, Accufab 75 mm race TB, 30lb injectors, 80 mm Pro-M mass air, Extreme energy cam 266.
Anderson ford power pipe the big one, Ford motor sport shorty headers, Bassani x pipe custom cat back with flows, World class T5, center force duel friction clutch.
1992 Deep Emerald Green Mustang GT Hatch, 5 speed, 2.73s, Mac fenderwell cold air intake, '93 Cobra MAF, Mac 70mm throttle body & spacer, Explorer intakes, Mac unequal headers & offroad pipe, Magnaflow catback, Walbro 110lph fuel pump, Jet adjustable FPR, MSD Blaster coil, Accel 8mm wires, FRPP aluminum quadrant, UPR firewall adjuster, stock cable, Granatelli upper control arms.
Waiting to go on: Granatelli lower control arms, and GT40 Iron heads!
1994 Mustang GT Runs Lean as Lean Gets 
