pardegt

I recently took ownership of an 87 Fiero GT with a 350 TPI installed.

The engine runs rich and you can smell gas as soon as it starts. Once it gets warmed up, it has trouble maintaining idle and will sometimes die. Plugs were black and exhaust has black carbon. The owner provided the info below and indicated it did run fine in the past but had been in storage and when he took it out a few years ago it starting running rich. They had cleaned the fuel tank, replaced the TPS and the wiring harness, thinking the spliced in corvette one had a short but that did not help.

350 bored .040
Comp cam p/n 12-402-4 (212 intake, 218 exhuast dur at .050, 114 lobe sep)
Dart Iron Eagle 10120010 heads (72cc, 180cc intake)
1991 Corvette TPI with TPIS throttle body
Painless wiring harness
EGR delete
7730 ECM with corvette chip that was updated by someone for current specs
Compression ratio - unknown
5sp Getrag

I checked the MAP sensor and found a brief dead spot so replaced it but that did not help either. Vacuum is a bit low at 15-18 so I did a smoke test and the only place I saw any escaping was the center of the TPIS throttle body between the butterflies and a bit around the shaft. The fuel pressure is at 40 with pump on, 38 at idle, and slowly bleeds off with the pump off (around 5-10 after 5 minutes)...normal I believe. I don't know what the injectors are, previous owner thought stock so I'm guessing they are 19 or 22lb. They are gray bodied with no markings so maybe Multecs? I thought maybe the fuel regulator was the culprit but there is no fuel that shows up in the connected vacuum line. I still plan to replace it though with an adjustable holley.

I would like to see what the ECM is doing but am confused by what files I need for Tunerpro RT. I purchased an ALDL cable and tried to gather info from these links I found:

http://www.gearhead-efi.com/Fuel-Inj...must-read!-%29

http://www.gearhead-efi.com/Fuel-Inj...Information-8D

http://www.gearhead-efi.com/Fuel-Inj...CM-information

http://www.gearhead-efi.com/Fuel-Inj...tunerpro+files

http://www.tunerpro.net/downloadBinDefs.htm

http://support.moates.net/tunerpro-rt/

...but I am confused as to which bin, ecu, ads, adx, xdf files I should use as there seems to be a lot of choices. I'm also not sure I understand the difference between bin and bin definition.

Any help to sort this out would be greatly appreciated.

RBob

iTrader: (1)

> understand the difference between bin and bin definition.

The BIN is the actual calibration in the ECM, while the BIN definition is the ECU/XDF file that defines the calibration layout for Tuner Pro.

Go to www.tunerpro.net, the downloads area for definitions, and grab the ones for the $8D mask.

RBob.

pardegt

Thanks for the info.

So the .bin is downloaded from my ecm and not needed before I connect? I guess I misread the must read tutorial as I understood all these files had to be uploaded to turnerpro first.

pardegt

I was able to run Tunerpro tonight and it has the air fuel ration highlighted in red.

I'm wondering can I upload my data log here to get some input? I tried but it does not seem to allow .xdl files.

ULTM8Z

You can e-mail it to me and I'll take a look at it.

ultm8z@yahoo.com

ULTM8Z

Ok, so I looked at your data. Hope you don't mind me replying here. I figure with people doing searches for diagnostic reasons, the information may help someone...

To the first order, nothing in the data is jumping out at me as problematic.

- You're getting into and maintaining closed loop, learn control is enabled and remains there for non-PE operation

- No codes are being set (though I'd need to see the bin file to know if the ECM is even watching for these malfunctions... custom chip, someone may have turned off the diagnostic switches, which would mean some of the "OK's" I'm seeing in the code flags are meaningless)

- O2 sensor fluctuates between 100 and 900 mV as expected

- All sensor readings are reasonable - CTS, MAT, TPS, MAP, etc...

- System voltages are normal

- Block Learn Cell varies normally with operating condition

- Spark timing seems reasonable (ECM probably executing on what's in the calibration)

- Target AFR is stoich for non-PE, drops down to 12.7 in PE which is reasonable


The only thing that could stand some improvement is the BLM... some areas diverge significantly from 128 ideal (getting up into the 140's and low 120's). But that's simply tuning to remedy, and I don't think is a symptom of the problems you're describing. The fact that the ECM hasn't maxed out on the BLM (Max = 160 and Min= 108) means it's able to trim the fuel to meet the needs.

As far as the ECM data looks, it seems relatively normal.

One possibility is something is malfunctioning on the "blind side" of the engine... i.e., the side without the O2 sensor. Depending on what side he stuck the O2 sensor on, the ECM doesn't see the other side of the engine and will not trim fuel for a malfunction there. May want to look at plug wires, injectors, etc, on that side of the engine.

Are you able to read the chip? I'd be curious to see what they did on the calibration.

pardegt

Thanks ULTM8Z...email sent with current bin from memcal.

ULTM8Z

Let's see... a few fundamentals to check before we get too deep into the diagnosis...

1.) What is you injector size? Calibration has 22 lb/hr. Need to ensure that accurately reflects what you're running.

2.) What is your base timing (EST connector disconnected)? The calibration has 6 deg BTDC. Your base timing needs to match that.

3.) What's the fuel pressure both with vacuum line on and off the regulator? This goes hand in hand with the injector constant. Is the regulator adjustable?

3.) Make sure your ignition is up to snuff. A simple coil replacement on my car recently made a HUGE difference. If you or the previous owner don't know the condition of the ignition system, you may want to just freshen it up... new cap, coil, rotor and plugs. For the wires, you can ohm them out and make sure they're all in family with one another... if they're suspect (burnt, frayed, cracked, etc), may just want to replace them too. If there's any tuning to be done, you do NOT want to be tuning around an unknown malfunction. You'll pull your hair out- trust me!

pardegt

I'm off to a rough start. The injectors have no markings on them and are grey bodied, based on what I have read, they are probably stock multecs. Since the corvette only came with a 350, I believe they are 22lbs that came with the tpi transplant. With the way the motor sits up against the engine bay in the fiero, I cannot see the timing marks to take reading. I will take a fuel pressure reading with the vac line off. Previous reading had 38lbs at idle and 40 with key over. I have an adjustable holly to put in when I take the intake off. I will also evaluate the rest of the ignition system.