Ford 2.9i EEC-IV problems.

[ajlelectronics]

I am struggling a bit with this engine in my project. I has run nicely not long ago and behaved well on the road.

Symptoms now are a rough idle trying to stall, an apparently very rich mixture and plugs being fouled enough to short two of them out. Plugs are deepest black, as is the exhaust.

Number 3 is interesting... popping and banging ceases when that plug cap is removed.

Tests included buzzing through all the sensors to the ECU, all Voltages look good too At the ECU.
The twin MAFs have been substitution tested.
Two full sets of new NGK plugs installed.
New air filter.
Fresh fuel in the tank and plenty of it.
New fuel pump.
Swapped the ECU for another identical.
Valve clearances all set.
Slight manifold blow repaired.
ECU earths improved.
Timing checked and set to 12 BTDC.
Disconnecting IACV stalls the engine immediately.
Disconnecting TPS causes the expected RPM drop.


KOEO code 11 pass.

KOEO will not complete tests because the engine stalls. On one occasion it did complete and gave a rear MAF error.

I am thinking Fuel pressure regulator, but is that likely to be completely open to through pressure if faulty? I have a gauge but as usual, I have loaned it out.

Injectors? Surely failed injectors would be weak rather than rich and they wouldn't all have stuck wide open.

 

[dobbslc]

What about the air temperature sensor?
If it thinks it's -10, it's really hot weather now it would run rich as hell.

 

[ajlelectronics]

What about the air temperature sensor?
If it thinks it's -10, it's really hot weather now it would run rich as hell.

The air temperature sensor is inside the air flow meter, rear. It gave in range Voltage at the ECU and an alternative unit changed nothing. I also swapped front and rear.

 

[ajlelectronics]

Still getting nowhere with this fault. I have had the injectors serviced (no fault found), replaced the IACV and throttle pot and I have swapped the fuel pressure regulator for another used one.

CO is around 12% at idle, which is not affected by the air bleed adjustments in the AFMs. CO drops to 9% if one AFM is disconnected and to 7.5% if both are disconnected.

The throttle stop is set correctly and I have the timing set to 12BTDC in service mode.

I have a fuel pressure gauge on order but I doubt that two fuel regulators will be faulty.

 

[R Kraft]

Failed O2 sensor ?

 

[ajlelectronics]

Failed O2 sensor ?

Doesn't have any.

 

[Matrixx]

Rich mixture would be affected by fuel & air, google says "The most common reasons why your engine running rich are a faulty MAF sensor, O2 sensor, or MAP sensor. It can also be caused by a faulty coolant temp sensor, IAT sensor, or a faulty fuel pressure regulator" can you see all these values on a diagnostic scanner? also you should be able to see the fuel regulation to see if the ECU is putting to much fuel in. popping and banging would indicate timing or firing sequence? just thinking aloud. is it looking for an O2 sensor?

 

[ajlelectronics]

Rich mixture would be affected by fuel & air,

Yes, too much fuel or insufficient air.

google says "The most common reasons why your engine running rich are a faulty MAF sensor,

It has a pair of Air flow meters, both have been substitution tested and the connections / Voltages buzzed through.

O2 sensor,

Doesn't have one.

or MAP sensor.

Doesn't have one.

It can also be caused by a faulty coolant temp sensor,

FCR gives expected reads. It is filthy rich at idle from cold, so faulty sensor would affect leaning for a warm engine.

IAT sensor, or a faulty fuel pressure regulator"

Swapped the regulator for one off another engine.

IAT is internal to the AFM and has been swapped around / substitution tested.

can you see all these values on a diagnostic scanner? also you should be able to see the fuel regulation to see if the ECU is putting to much fuel in. popping and banging would indicate timing or firing sequence? just thinking aloud. is it looking for an O2 sensor?

The popping and banging was down to me, I had the firing order incorrect.

Fuel pressure I cannot see until Saturday when I have a gauge arriving, hopefully.


So you see why I am stuck?

 

[dobbslc]

Have you double checked the cam timings and done a compression test on all cylinders?
Maybe worth going back to basics here just in case something daft has happened.

 

[Bullet2012]

Have you double checked the cam timings and done a compression test on all cylinders?
Maybe worth going back to basics here just in case something daft has happened.

Is it one of the engines that had the fibre timing gears ?

 

[octo0072000]

what does it run like if you disconnect the MAFs

 

[octo0072000]

Is it one of the engines that had the fibre timing gears ?

think it was the Essex that the fibre gears if i'm right this is the later cologne engine 2.9EFI twin plenum

 

[Chippie]

The 2.8 Capri Cologne engine had fibre gears as standard…metal ones were aftermarket I seem to remember..not sure about the 2.9….

 

[ajlelectronics]

what does it run like if you disconnect the MAFs

If I disconnect one, the CO drops back to 9%. If I disconnect the other, it drops again to 7%. The engine idles slightly better.

One potential lead...

I have a fancy FCR (Lucas 2000/1500) and one of its functions is to measure all ECU pins to ground. The AFM responds but from 0.2V to 2.6V rather than twice that. I am still finding my way around it, but that is something I will be investigating.

 

[ajlelectronics]

think it was the Essex that the fibre gears if i'm right this is the later cologne engine 2.9EFI twin plenum

Yes, this is the 2.9i Cologne. Ex Mk3 Granada. Single plenum.

 

[ajlelectronics]

Have you double checked the cam timings and done a compression test on all cylinders?
Maybe worth going back to basics here just in case something daft has happened.

I haven't because there are no other worries than 12% CO, but it is certainly a fallback plan.

 

[octo0072000]

stupid question but is it getting air blocked filter /air intake picked up a rag off the road when did it start running rough what did you do just before that

 

[8ob]

Is this a retro install? Just wondering if things like the pcv have been plumbed in or blanked off/bypassed.

Bob

 

[ajlelectronics]

Is this a retro install? Just wondering if things like the pcv have been plumbed in or blanked off/bypassed.

Bob

I did the transplant and everything came with the power plant, even the loom, modified to suit. I have another line of enquiry too, the Lucas FCR can't tell that the ignition is on, so although it all starts fine, I am going to be looking at that pin. It is fed by the "injection" relay which really is just an ignition relay.

File attached is a simplified wiring diagram for that power plant in a Middlebridge. My project should be similar.

 

[8ob]

I did the transplant and everything came with the power plant, even the loom, modified to suit. I have another line of enquiry too, the Lucas FCR can't tell that the ignition is on, so although it all starts fine, I am going to be looking at that pin. It is fed by the "injection" relay which really is just an ignition relay.

File attached is a simplified wiring diagram for that power plant in a Middlebridge. My project should be similar.

I was thinking about the rich idle, pcv is a measured air admittance so if it was blanked off would or could cause a rich idle.Just thoughts.

Bob.