elio3848

New Member
Jan 5, 2020
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Rochester, MN
I have a 1995 mustang gt automatic with a built engine, it has a 331 stroker kit, stage 2 trick flow top end kit that comes with the trick flow stage 2 camshaft and full exhaust with x pipe high flow mufflers and around 10.5/1 compression. I just bought this car and the past owner gave me 2 SCT tuning chips saying that all I need to do is take my car to a dyno shop and get it tuned. Well, the car has been at a "professional dyno tuning shop" for the past week and I recently received an email saying he can't get the car to run leaner he said the car is too rich and doesn't know why.

Any advice?!?!?!?!?
 
Sounds like you need a new tuner.
You could get a quarterhorse setup and learn tuning yourself, or step up and go with a megasquirt based setup. I’d choose option 2 as there are more people versed in tunerstudios than binary editor/tuner pro
 
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Sounds like you need a new tuner.
You could get a quarterhorse setup and learn tuning yourself, or step up and go with a megasquirt based setup. I’d choose option 2 as there are more people versed in tunerstudios than binary editor/tuner pro


supposedly the tuner told me that the sct chip he flashed is already set up good and the tune on the computer is compatible with the build but there is something wrong with the wiring harness or the computer from the factory itself is bad
 

what would need to be changed entirely?
 
HiTech Motors out of Elk River MN
I looked these guys up, their track record for tuning isn’t good, especially if you get into fb reviews.

If maf and injectors are functioning properly, a half competent tuner should be able to dial in fuel - especially on a dyno. You’re better off getting a remote tune done over Dealing with somebody who doesn’t know what they’re doing.
What did he say your a/f was at?
 

at idle i was told 10.8/1 after he "commanded" 25/1 in the tune because the car was running so rich
 
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at idle i was told 10.8/1 after he "commanded" 25/1 in the tune because the car was running so rich
If he’s using commanded fuel to dial in Actual fuel then he is a terrible tuner.
Get your money back and hit up Willie at dirtydirtyracing. He does remote tuning.
 
I would need to know more specifics of your combo. For example what MAF brand and injector size are in the car?


Sorry for the late response,
I recently put in 30 lb injectors in and sent my MAFback to PRO M to be recalibrated as it was previously calibrated for 42#, but the troubling part is it still runs like sh*t. Weirdly enough I am able to keep the car running (blowing plumes of white smoke) when I disconnected the MAF and take off the filter (I'm running a MAF where it is mounted on the filter), and when my air filter and MAF are installed the car won't even fire when turned over, I'm thinking that it's running so rich that the little amount of air restriction the filter provides is the choking the engine off totally.

I am now looking into to see if I have ECM damage because I get the code 511 (Read-only Memory) from when I put my diagnostic scanner on it.
 
Sorry but the reply above is not correct in any respect. A 511 is a standard error code when you have a piggy-back chip installed. Your computer is not toast.
If you've had your MAF calibrated to your injectors, you need to remove your piggy-back chip with the questionable tune on it. Otherwise, the tune needs to be corrected to the new MAF curve. If you have a 511 after removing the chip, then you may have a problem.

The plumes of white smoke are most likely an extremely rich condition, likely nothing to do with the head gasket. That's a common failure, but as you mention it's running pig-rich, that's just raw fuel coming out of the tail-pipe. Especially if it smells like raw fuel and makes your eyes water.

Step 1 - remove piggy-back chip if you haven't already and give things a try.

Step 2 - you may have a stuck-open fuel injector. your tuner may have been oblivious to this (they often aren't good with mechanical problems). check your fuel pressure. if it goes to zero quickly after shutting off the car, you may have one that is stuck and is dumping all of the fuel into a single piston (leaving other cylinders lean and barely running). Your symptoms are identical to mine when I had that happen. This type of mechanical failure cannot be corrected with a tune. If you are running 'Bosch Green Giants' especially if sourced from eBay, be very very skeptical and assume this is your problem.

- If you suspect this is true based on fuel injector brand and / or fuel pressure readings, replace injectors with a good set.
- Change your oil because it's now filled with fuel and will wreck your engine.

Step 3 - if you have verifiably corrected the fuel injector situation in step 2 (don't try and skip that step), installing an adjustable fuel pressure regulator gives you some level of control over fueling. My calibrated Pro-M was calibrated too rich by the factory. Turning down fuel pressure a pound or two allowed the computer to get into the range where it could comfortably adjust fueling.
 
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When I remove the chip I just get the codes stating the car is running rich lol. The ecm isn’t damaged the car is running exactly how it should be with a stock ecm and big cam.

I have recently replaced the injectors (upgraded from 19# to 30#) and the car runs a little better but still super rich. Plus the car holds fuel pressure.

The car already came with a adjuster fuel pressure regulated and I set it to 37-40 psi.