Rich Running Falcon- Just After Opinions

[r32-25t]

No it will lower a the revs due to the tps still reading closed and can actually cause it to hunt at idle (provided the ecu uses the tps as a secondary load source which the falcon does)

[AngryRB]

replaced the MAP sensor and O2 sensor today, also reset the battery then took it for a drive and it drove perfectly, but then half hour later went to drive it and it was like

a pig, on partial throttle it would cut out on me, I had to pump the throttle to keep it going, seems to settle enough to drive it but super sensitive just dropping it in D.

Took it to exhaust shop and got CAT and Resonator replaced ( cat was collapsed), for the first few Km's it was jolting and playing up then just started running sweet again so I

don't know if shes fixed yet or not.

Have a new symptom which has appeared, that is when im cruising alone at 2000rpm and engine braking, it will all of a sudden drop down a gear violently like if you'd given it the beans, and also

as you are slowing down it drops the low gears in as if it was manual box , I think the car is possessed..

Items replaced so far are

-Coilpack, plugs

-Injectors

-MAP sensor

- 02 sensor

- cleaned fuel rail

-CAT and resonator

- cleaned IAC

- Sprayed manifold with carby cleaner and no reactions

ALSO- car has dual fuel and the problems happen on BOTH LPG and on 98unleaded

next is coolant sensor and Throttle position sensor and have the gearbox checked..

Edited April 28, 2014 by AngryRB

[mad082]

It may possibly be the tps, since it can make the gearbox do funny things. If it had a sudden spike in voltage then it would think you had floored it and make it drop back a gear.

[gtr jet]

It may possibly be the tps, since it can make the gearbox do funny things. If it had a sudden spike in voltage then it would think you had floored it and make it drop back a gear.

I'm guessing this too. I remember my EL did similar things when the TPS gave up.

[Cowboy1600]

Sounds like your ECU is borked. Reset it again and see it what happens.

EDIT: Wait, Just read the second part Sounds to me like it was your ECU struggling to cope with a blocked exhaust.

Edited April 28, 2014 by Cowboy1600

[533 RYC]

I was a Ford mechanic for a few years. I've changed 6 TPS's in my time there due to a flatspot, cutting out, running rough. They tend to wear out right on the cruise spot, where it sits most of the time.

Check with a multimeter. Unplugged, check resistance from idle to WOT. If connected, probe & check voltage from idle to WOT.

In both cases of diagnosis, you'll see zero volts or infinite resistance when you hit the spot.

[AngryRB]

I was a Ford mechanic for a few years. I've changed 6 TPS's in my time there due to a flatspot, cutting out, running rough. They tend to wear out right on the cruise spot, where it sits most of the time.

Check with a multimeter. Unplugged, check resistance from idle to WOT. If connected, probe & check voltage from idle to WOT.

In both cases of diagnosis, you'll see zero volts or infinite resistance when you hit the spot.

In the Gregory's manual it says to check for voltage, I assume this is what you mean, I checked today and found the wires to the sensor give the

5volts so computer ok, the actual sensor is not giving me any voltage. Not sure if I'm doing it properly or the sensor is rooted, while connected

the manual says to back probe the middle wire which I take it means slice into it and place a probe on there and ground the other probe of multi-meter???

if so then the TPS is dead, interestingly I can start the car with it disconnected and seems to idle fine.

I swapped my other falcons TPS over and tested that too and it gives the same zero voltage reaction to the throttle, whats the chances of 2 dud

sensors in a row. hmm

The last drive of 20mins has been smooth, the car is definitely better with the replaced cat, has a lot of low down torque but will

have to see if she's still using the 20L/100kms.

Edited April 29, 2014 by AngryRB

[mad082]

If it was totally dead it wouldn't change gears. Well at least that was the case when I unplugged the tps in my Commodore trying to diagnose a miss a while back

[AngryRB]

Update- ran good today for about 30mins then pulled up at traffic lights and it had a big fit, big clouds of black smoke puffing out, had to pump the throttle just to get it to move. Dropped into autoelectrician who hooked up his scan tool, and no fault codes come up, TPS is working, leads tested and good,

managed to get it home with it filling the street with black smoke, pulled into driveway and its idling smooth again,

when I have it in neutral and increase the revs slowly its smooth til 2000rpm where it bogs down and misses badly, at 3000rpm its really trying hard not to go further.

Anyone have any more suggestions, note on both LPG and Petrol it does this, for some reason it pours the fuel in but there's no fault codes..

[mad082]

Injector issue?

[Ben C34]

Injector issue?

Runs bad on lpg and petrol though....

[mad082]

Of course. My bad.

[533 RYC]

Falcons are known to break the tip of the needle off injectors, creating a constant miss fire & running rich. The AU's also suffered from valve recession & worn guides.......

[White GTS-T]

I bet your fuel pressure regulator has a hole in the diaphragm and is sucking in extra fuel under vacuum. Remove the vacuum line from the reg as the car is running and I bet you fuel pours out. As a mechanic, I've seen this several times on Falcons and the symptoms are exactly as you describe. Also, I've seen gas systems that keep the fuel pump running, even when switched to run on LPG, (they just cut the signal to the injectors) so the rail would still be pressurised and the hole in the fuel reg diaphragm would still be sucking in more fuel.

[White GTS-T]

Either that, or the vacuum signal hose to the map sensor has blown off or has split, due to a backfire. I'd wage money, that it was either of these.

[533 RYC]

If this is the case Tim, why is it intermittent? If what you described is the case, then it would happen all the time.

[White GTS-T]

It seems that way because the symptoms change with engine conditions. i.e. engine temperature and manifold vacuum. e.g. You lift your foot off the throttle to take a corner, this increases manifold vacuum, which results in more raw fuel into the manifold and as you go to take off again, nothing happens, or it stalls. The car runs okay when you first start it up cold in the morning, but gets progressively worse the more you drive it. If you flog it then it seems to 'clear up'. But go to start it again after it's been hot and there's still pressure in the rail and it runs like a dog again. After sitting idling at the lights, you go to take off and it wont rev. etc.

[533 RYC]

Simple then, either vac test the pressure reg with a vacuum pump or prime the fuel system with the vac line removed from the reg & see if fuel comes out.

[Ben C34]

Simple then, either vac test the pressure reg with a vacuum pump or prime the fuel system with the vac line removed from the reg & see if fuel comes out.

Fuel will definitely still come out with the vac lone removed from reg.

Perhaps that could solve the problems, spray car with fuel, light, turn 360 and walk away...

[niZmO_Man]

Fuel will definitely still come out with the vac lone removed from reg.

Perhaps that could solve the problems, spray car with fuel, light, turn 360 and walk away...

lel