4.3 V6 Chevrolet Mercruiser Multi Port Fuel Injection
My truck is a 86 Mighty Max Spx and the only thing stock about it, is it’s looks. 2001.7.jpgDoodle truck1.jpg3chop.jpg
I’m running a 97 4.3 Chevrolet with a TH-350 with a Edelbrock 500cfm carb.
But this is coming to a end.
I recently purchased a GM 4.3 Vortec Mercruiser intake manifold, which is not a spider (poppet style) injection system that come stock on the GM Vortec 4.3 vehicles. I picked this up off ebay for $309.00. Brand New Loaded. The included injectors are Delphi EV6 24lbs/hr. @ 43.5psi. units with USCAR connectors.
They work out to about 27lbs/hr. at this fuel pressures of about 53psi. These connectors are used on some Ford SVT models and the LS2 and LS7 engines. They are high impedance (~14ohm) and the same physical dimensions from o-ring to o-ring as standard Bosch type injectors.
USEABLE .....for naturally-aspirated L31's. Anything blown or having more cubic inches will want more of an upgrade in flow than the OEM Marine injectors can provide. (The whole point of this swap is that be able to put any size injectors in there you want!)
Standard EV1 injectors will also fit the rails and a harness must be made anyway. Connectors for the "oval" USCAR connectors are available. GmVolvo4300 MPFI.jpgEV6 fuel injector connector plug pigtails.jpg
The stock 96/97 fuel injection systems were junk along with the GM black box ecu/pmc. And showing the Plenum is off the intake to show the spider injection system. The harness plugs and black box ecu. image_1.jpgdownload (1).jpgdownload.jpg
Here's how Mercruiser and Chevrolet used their 1998/99 ECM 555 for "batch fire" fuel injection system.
(Batch fire, meaning all injectors fire all at once awaiting for a intake valve to open.)
Speed / Density Theory and Operation Speed/Density Theory.
All MerCruiser EFI engines operate on the fuel injection strategy called ªSpeed/Densityº. This means that the ECM primarily looks at the engine's speed and the intake manifold's air density in order to calculate the correct amount of fuel to inject. The engine requires an air/fuel mixture of approximately 14:7 to 1 in the combustion chambers. Since the EFI system doesn't control air flow, it must determine how much air is flowing through the engine in order to calculate the correct amount of time to fire the fuel injectors. The net result is that there must be 1 part of fuel for every 14.7 parts of air going through the engine. Since the engine is basically an air pump, we know that an engine is capable of pumping a certain (maximum) amount of air at any specific rpm. The actual amount of air it pumps (at a specific rpm) depends on the density of the air in the intake manifold. The air density (in the intake manifold) will vary depending on rpm, throttle plate position and barometric pressure. If the air density in the intake manifold is known, the actual amount of air flowing through the engine (the ªAir Massº or ªMass Air Flowº) could be calculated. This calculated (and the actual) air flow is a repeatable function, meaning that at a specific rpm and a specific manifold absolute pressure reading, the air flow through the engine will always be the same. However, in the speed/density system we do not actually calculate the actual air flow. Instead, the ECM measures the rpm and the air density, then refers to a programmed ªlookup tableº in the ECM's EEPROM. This lookup table will be programmed with the correct fuel injector information for every rpm and density reading. The programming engineer has to come up with these figures, because the ECM is not actually calculating the Mass Air Flow. The speed-density system depends on the engine being unmodified (from its original production state). If we change the volumetric efficiency of the engine in any manner, the amount of air flow for a given rpm and air density will change, causing the ECM to deliver the incorrect amount of fuel. Any modification to the following components will influence the air flow through the engine, throwing the speed-density system out of calibration. 1.Pistons and combustion chambers (anything that changes the compression ratio). 2.Camshaft changes (effecting the valve timing, lift and duration). 3.Changes to intake and exhaust valve size, as well as ªporting and polishingº 4.Installing different intake and/or exhaust manifolds. 5.Installing a different size throttle body and/or flame arrestor. Mass Air Flow Systems Mass Air Flow systems actually measure the amount of air (or ªAir Massº) entering the engine, so they generally can compensate for modifications or changes to the air flow through the engine. While these systems are generally considered more accurate, they are generally not as robust (and cost effective) as the speed-density system. Mass Air Flow systems are typically used in automotive applications to meet stringent emissions and fuel economy requirements. One method of measuring the mass of the air flow into the engine is the ªHot Wireº system. A small wire is stretched across the air intake. An electrical charge is run through the wire (causing it to heat up). As air flows over the wire, it changes the temperature of the wire, which changes its resistance (and the resulting current flow). The ECM can pick up this change in current flow and calculate the amount of air entering the system. EFI SYSTEM COMPONENTS/OPERATION - 1-1 MerCruiser EFI III (1004) 2
Another method of measuring the mass of the air flow into the engine is the ªvane-typeº Mass Air Flow sensor. A movable vane is mounted in (protrudes into) the air intake system. The rush of intake air through the sensor causes the vane to be deflected. The deflection is measured and a signal sent to the ECM. NOTE: The speed-density system is more than accurate enough for our marine applications. The additional reduction in emissions and the resulting increase in fuel economy (with the Mass Air Flow system) are negligible. But when automotive manufacturers must meet emissions standards, they often have to take small improvements where they can find them. Speed/Density Operation The engine's RPM is easily determined from the REF HIGH signal on systems with EST ignition, or the timing signal from the Thunderbolt Distributor's hall-effect sensor on small-block MEFI 3 models. To determine the density of the air in the intake manifold, we need to know the intake manifold vacuum, which we measure with the MAP (Manifold Absolute Pressure) sensor. It is important to remember that a MAP sensor measures the manifold pressure above absolute zero (like a barometer), while a conventional vacuum gauge measures the manifold pressure below the current atmospheric pressure. The use of the Manifold Absolute Pressure Sensor allows us to compensate for variations in atmospheric pressure due to weather and altitude changes. A conventional vacuum gauge would not provide us with this needed information. NOTE: While the temperature of the air does affect its density, not all engines use an IAT (intake air temperature) sensor. If no IAT is present, then the ECM assumes 75 degree Fahrenheit for all density calculations. If an IAT is present, then the ECM can more accurately determine the air's density. However, the amount of correction the IAT adds is a relatively small amount (approximately 10% maximum change in fuel flow). In review, our standard, unmodified production engines flow a repeatable (and therefore ªknownº) amount of air at any specific engine rpm and manifold pressure. With this knowledge, the ECM can be programmed to deliver the correct amount of fuel from the combination of the speed sensor (distributor signal) and density information (from the MAP sensor). It is often said that the speed-density system runs ªin theory aloneº, since the ECM doesn't really know how much air is flowing through the engine, it is just assuming it knows how much (based on the repeatability of airflow theory). In reality, the system is simple, rugged and works extremely well. But, the ECM cannot compensate for changes in volumetric efficiency of the engine.
A note on the MEFI 3 (GM 98/99 software) the PDF says,
(13) oxygen sensor inactive, (24) Speed sensor inactive, (31) Governor not tracking, (32) EGR valve not tracking, (54) O2 sensor LEAN (55) O2 sensor RICH ….foot notes, are not used in 98/99 ECM 555. http://translate.googleusercontent.c...TZCjzWvaQCqP2Q <---if you click this you will download the PDF, just saying. for me it was a good read and I'll refer back to it later?.
The newer marine ECM's to run this intake (96 to 2006 vortec) cost about $1700, they are sequencial and they do fail.
So now you know where we are going and why. Let's go on.
You can buy a Stand Alone engine harness for about $470 for the vortec v6, but it will come with the spider injection single plug and you can use the electronic transmission or go without like I am doing. http://www.hotrodharness.com/fuel-in...harnesses.html
The spider injection ‘is sequential, meaning it injects the fuel just before spark ignites. The marine intake has 6 separate injectors so the injector harness needs to be extended which I will cover later.
Important note here. if I can?
I’ve done so much reading on forums for research and seen the pain in the ass of reading post after post on trying to find the answers I really needed was 3 hours of reading.
So this thread and in this main post will I will try to contain all the questioned asked by a forum member and the answer will be here in this #1 post to stop the spread of important information being spread though out the thread.
This is going to get very technical for some and take a while for this thread to get written. so l will add to it as my time allows.
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This is my 97 S10 engine harness and we will be changing it to fit a 2002 blazer which uses a xxxx0411 pcm, they are tunable.
Gm uses the VAT System, the “chipped key” which can be as they say, masked or shut off. More on this later.
So with that said, if my attempt fails I can buy a custom Vortec v6 stand alone engine harness with a 4 wire hook up and turn key.
Starting out I still need the stock configuration of the harness so I pegged to a piece of plywood and marked each and every wire. If I checked once I've checked it three times. Accuracy here counts.
Here's 15 GM vehicles wiring diagrams, downloadable PDF files. https://docs.google.com/folderview?h...hiODIzMTRhNzdh 20141229_192158.jpg20141229_192147.jpg
So here I have all my wires identified and triple checked starting to remove parts of the harness I’m not using, such as the VSS (vehicle speed sensor) or the clutch switch . On the lower left is the wiring pulled out and no longer being used. (there's more later). Removed from harness.jpg
Next is the fuel injection harness. Fuel system harness removed.jpg
So yes, I am completely taking each and every mini harness out of the makings of a full harness. (We have ZERO room for mistakes). 20141230_121401.jpg20150104_204717.jpgCKP, Crank sensor.jpgEngine Coolant Temp and Throttle position sensors.jpgFuel Injection.jpgHO2S sensors, right and left.jpgIdle Air Control.jpgKnock and Oil sensors.jpgMAP Inake Air Temp.jpg
So now here we are at sensors, we've discussed this on here on the MSD sticky link. http://www.mightyram50.net/vbulletin...D-Thread/page2
Your truck and my engine run off of hall sensors, Gm uses a three (3) wire hall sensor on many ciruits such as the TPS, CKP and the CSS in the GM distributor. Some run off just the PCM.
One "key powered hot" (GM, pink),
One signal. (GM, in many colors)
One 5 volt. ref (GM, in many colors) GM chose to use a 5v. ref. (makes can differ?).
+[The 5 volt reference is used like a on a gas pedal or Throttle position sensor. 5 volt could be at idle, 1v = Wide Open Throttle (WOT)]+
The PCM use the signal and the 5v ref to operate, this why every wire must be accurate or we'll fail at the twist of the ignition key.
I'll explain a bit on the GM 0411. From 98 to 2002 in the processor alone they list here is a 512K and a 1MB, means twice as fast.
I'm Considering, OmniTuner DUAL-FLASH is a device allows you to install two separate flash chips in one Powertrain Control Module. Most GM Generation III applications are supported but when ordering specify which PCM you have so that the DUAL-FLASH has the proper flash chips installed. GM used both 512K and 1MB flash chips in the GEN III PCMs. The DUAL-FLASH replaces the flash chip that was installed by the factory with two separate OEM flash chips that individually appear to the PCM as a single flash chip when selected. Through the use of a switch of your choice you have the ability to select which one of these flash chips is used by the PCM. You have the ability to switch between flash chips only when the ignition is in the “off” position to prevent accidently switching between flash chips when the car is running. Possible applications for the DUAL-FLASH include tuning a vehicle for multiple fuels, assuming this tuning is compliant with emission regulations. You can use ethanol based fuels when available and switch back to conventional fuels when desired. Additionally you might choose to tune one flash chip for fuel economy but leave the other flash chip stock. Any tune that you can flash to a stock PCM can be flashed to either one of the flash chips of a DUAL-FLASH enabled PCM. Cost $475.00 http://mrk-motorsports.com/pages/store.html
This is my core 0411 pcm and plugs with coil and ICModule I will use. 0411 pcm and plug connections.jpg20150102_132141.jpg20150102_134512.jpg
And Yes, even though they can turn off the VATs and flash a baseload for engines, some tuner programs you need a VIN#.
(Any VIN# including a junkYard VIN#, mine engine is a "W") see the W?
It has noting to do with being a legal document, it has to do with tuning and configuration to tune the specific engine. 20150110_093907.jpg
Now that I've triple checked each wire and clearly know the C1 and C2 connectors of the pcm. I've wrapped them up for the (later) removal. There are as of now 11 on blue C2 and 18 wires being removed leaving 23 on red C1 and 32 on blue C2. Blue C1 wires marked for removal.jpgRed C2 wires marked for removal.jpg
The other day I went back and got the O2 harnesses off the 02, well, as much as I could get. I've found that this PCM talks much more on personal level
to the engine parts way different. it is said that the 97 O2 system will work ok, but why would one not up grade and let it communicate and drop some more wires. 2002 right and left bank Oxygen sensors.jpgHO2S sensors, right and left.jpg97 oxygen sensor wires removed.jpg
It appears I cut just a tad too close. If I recall correctly this is called SP-100, which is just a splice for the 5 volt ref on the HO2sensors. These 3 wires are from the three sensors, Bank 1, Bank 2 and bank 1 sensor 2 into the pcm. Note here, Bank 1 sensor 2 is behind the catalyst and not needed in my application. 20150106_173647.jpg
I ordered some more parts. 2001-2004 Chevrolet S10 Knock Sensor Connector,2002-2005 Chevrolet Blazer Oxygen Sensor - Delphi ES20319,
1985-2004 Chevrolet S10 Water Temperature Sensor - Delphi TS10075, 2001-2005 Chevrolet Blazer Knock Sensor - Standard Motor Products KS115 knock harness two wire 2002.jpgHo2 sensor.jpg2002 Chevrolet Blazer Water Temperature Sensor.jpg2002 Chevrolet Blazer Knock Sensor.jpg
This is the 97 one wire knock sensor hanging with the oil pressure sender. Knock and Oil sensors.jpg
This is exactly why you check once, check it twice and check it thrice times.
The Air Idle Control is the same but different configuration and color of wires. GM engineers are sneaky SOB's. 20150112_101012.jpg
Here's are some facts on PCM/ECUs most do not know.
Engine Wiring Harness Rework Service and PCM Programming http://www.my-efi.com/my-efi-pricing-list.html
For All LT1 LT4 4.8 5.3 5.7 6.0 6.2 7.0 7.4 8.1
LM7 L59 LY6 L76 LS1 LS2 LS3 LS6 L99 LS9 LS7 LQ4 LQ9
LS4 4.8L 5.3L 6.0L 6.2L 7.0L 7.4L 8.1L Engines and More.
We can also rewire Jeep and Ford Engine Wiring Harnesses.
ECM PCM ECU TCM Tuning Programming Parameters
VATS or Vehicle Anti Theft Delete. Engine Will Not Run Unless Deleted From ECM PCM
Reduced Spark Knock
Advance Timing
Abuse Mode and Torque Management Delete
87-93 or 91-93 Octane
Axle Ratio And Tire Size. This Is How Shift Points Are Determined And Exact Numbers Should be Given
EGR Delete
Air Pump Delete
Air Conditioning
Fan On Off Temperatures
MPH Limit Deletion
RPM Limit
Shift Points
Shift Time Reduction
MAF Larger
Injectors Larger
Camshaft
Intake
Map Sensor
Throttle Body
Foot Pedal
Codes Any And All
4L60E 4L65E 4L70E
4L80E 4L85E
6L80E
6L90E
T-56
700R4
TH400
TH350
NV3500 NV4500
Any Transmission
Shift Firmness
And More
From all the web sites I've checked out, this man has been the most helpful. Here's a email from Jeff.
Hi Rick,
The 2002 pcm should be a 12200411 service number. As long as it came out of a 4.3 v6 vehicle, the pcm you have will work. If it came out of a v8 it will need a crank relearn from the dealer which can cost 75.00 or more. I do have a 12200411 v6 pcm here. They are 175.00 plus 19.00 shipping.
Typical things to delete would be vehicle anti theft so it starts and runs. The rear oxygen sensors and emissions can be deleted. The oxygen sensors from any 96-02 v6 4.3 all work the same but have different plus. Ones a flat 4 (prong connector) on older years and the other is a square 4 (prong connector) on newer ones sometimes. If you run oxygen sensors you need the driver side and passenger side. They are bank one sensor one and bank two sensor two. You can delete the third oxygen sensor for the catalytic converter. You want to keep the mass air flow sensor and intake air temperature sensor. You can have all functions and codes deleted for the transmission too. There are many codes and functions you wont need and things that can be changed.
I dont normally see people add a newer pcm to an older harness. As long as you have the proper grounds and wires in tue right locations you should be okay. I do have a 01-02 4.3 v6 harness here. I dont know what the mercruiser intake looks like.
If there's anything else let me know.
That's a good response from Jeff, I will be using him. Others sites just have you fill out a form and if you chose wrong, it's on you for what you do not know.
Dang it, I some how ordered the wrong connectors. oh well?
YES please do say if you see something that doesn't make any sense.
I am illiterate and human, I once was a dumb kid.
These are going on my doors in most forward and lower position. I think it works very well with my truck. images.jpg
Last edited by Rickdees; 01-18-2015 at 10:27 PM.
Reason: building a thread
4.3 V6 Chevrolet Mercruiser Multi Port Fuel Injection
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