ALRIGHT Where to start.....

as many of you know i have dropped a 5L windsor into my EA falcon.
It had a few teething problems that i have sorted but there is one that i haven't. where it wont rev past 3,000.

On friday i purchased 2 air/fuel ratios gauges and 2 brand new ford HEGOS, to see what was going on.

Now all the manuals and documents i can find show that the 2 Hego Pins for the left and the right Hegos should measure from 0.0 to 1.0V when running.

I have a constant 4.5V even when the hego's are disconnected.
I unplug the hegos and nothing changes engine running wise. Drives just like it did before.

I have triple checked the wiring, every wire goes where it is supposed to on the ECU.

So is my ECU stuffed or what?

For Background information, i disconnected the wiring to the ECU from the hegos on saturday night to run the gauges and the engine runs in stoich until 2,800RPM then leans out to all buggery.

I have an AUXR8 throttlebody & Spacer/EGR Remover, Ported Upper to suit new throttle, Extractors and dual 2.5" straight through Exhaust.

She picks up sweet right until the lean at 2,900 where it hits the wall.

The fuel tank is an aftermarket race cell with a High Flow Race Pump.
& i have placed a new Fuel Filter in it.

So any ideas gurus, ECU, Injectors, Something going awefully wrong?
Maf Voltages read right as well and TPS is set "edit" too.

Last edited by EACRUISER on Wed Sep 03, 2008 12:20 pm, edited 1 time in total.

Oh and the HEGO inputs on the ECU read 4.5v even with the wires cut right near the ECU. so there is no input on those wires.

Its like the ecu is putting out the voltage when it shouldn't

TPS should be .98volts.

Sorry with the sms writing, yeah TPS is set to .98v

the 2 was meant to be too

can you list the bits,motor\box\ecu\intake\car model,to give us some idea where your at and whats missing in the set up.

FORD FALCON 1990 EA Series II.

EB XR8 5.0L complete.
With Ported and polished Intake Manifold to suit AU XR8 Throttle Body & EGR Spacer.

Genie Extractors to Dual 2.5" straight through Exhaust. no crossover.
inc 2x brand new ford HEGO's

Complete EBXR8 Loom including Computer.
Ford Motorsport Fuel Pump.
RCI 25 Gallon Fuel Tank.
Stock v8 Injectors, Fuel Rail & Fuel Regulator.

Ford 4 speed Auto. Upgraded, stock v8 Stall convertor and Flywheel.
With stock Transcomputer.

Using the ford service documentation, Maf sensor & TPS voltages are correct.

The Hego's are not though. measure 4.58 volts instead of the 0.0 to 0.98volts they are supposed to

cut the hego wiring, off the cut hego wire its 0.0-0.98v off the ecu side its 4.58v
Hence why i think its ECU related.

If you need any more details or other info, please ask, need help.....

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With all that while driving it leans out like i said above at 2,900rpm. Any ideas.

was the xr8 motor auto or manual,can try the error codes for a clue,might confirm a problem with the ecu,did you also get the bem as well or up graded.

how strong is spark at 3000 rpm and can you check the tfi module on the distributor.

Standard XR8 ECU non smartlock model.

Was a Manual v8, but have an auto xr8 computer and bellhousing stall convertor etc.

Wired the transcomputer from the 6 cylinder loom into the xr8 loom pins.
According to the wiring diagrams i had gotten from the net.

Spark appears strong. fuel drops off dramatically.

On a side note, someone following me said they see flames when it hits this 3,000rpm wall and rev bounces. coming out my exhaust. Its like its hitting a limiter.

That EEC could be screwy. However there is no way will you have a Voltage on the HEGO inputs unless it has crossed wires with Vref maybe. Are you measuring the input pin with reference to HEGO ground? Is the HEGO ground(orange wire)bolted to the rear of the intake as it's supposed to be?

Are you using a second TPS for the auto transmission module? Could be another issue here.

"Is the HEGO ground(orange wire)bolted to the rear of the intake as it's supposed to be?"

No idea, about the wire, thanks will check that wire.
but yeah measured it with reference to hego ground and then to just body ground, and both came back identical. 4.5v.

I have 2 TPS on the throttle body. TCU has one and ECU has one.

Hence the reason i am hitting my head on the wall. checked all the wiring 6 times now. no short on the v-ref unless its internal in the eec.

So the ECU might be cactus.

This is starting to get annoying, almost Thinking of ripping all the injection off and the wiring loom out.
And grab an Edelbrock RPM Performer and Holley 650 D/P. and then swap out the auto for a manual.

If the conversion is from an EB/EL and youre getting the 4.5 at the o2 sensors make sure the airflow meter is functioning.If its knackered it`ll have the 5V reference at the PCM. (ECU). Ive cleaned em b4 with carby clean but chances are the hotwire in it(look thru you can see it) is snafu. If the fuel pressures are sweet and its a stock system it`ll be the airflow meter. But in conversion world................................................?