Thread: Disco Black spark plugs?

Had the same issue last time I changed my plugs. Getting to the point of craziness with my car using too much fuel. Might be worth checking some of the stuff Westonben mentioned in the Idle problems thread.

AFM/MAP hasles but it might also be the fuel pressure regulator sticking.

hows the oil, when they start to burn oil that blackens the plugs up fairly quickly but only leads to using more fuel from you booting it harder to keep the power output up.

Originally Posted by Blknight.aus

AFM/MAP hasles but it might also be the fuel pressure regulator sticking.

hows the oil, when they start to burn oil that blackens the plugs up fairly quickly but only leads to using more fuel from you booting it harder to keep the power output up.

Definitely. I'm whacking a pressure tester on it tomorrow to see what's up with it. The only thing though is that not only can that stuff up the mixtures, so can the:

MAF
Intake air temp sensor
Coolant temp sensor
Fuel temp sensor
and probably the LHR door handle if you pull it too fast

I've just been trauling through the workshop manual and while it tells you how to replace all of these parts.... There's no test procedures telling you hot and cold resistances. Back when I was a Ford mechanic, we could test all of these things. Even check vs temperatures using a thermometer etc. All of the figures were in the manuals.

Someone throw me a bone here

Not having looked up RAVE stuff for the V8 I cant remember if its there or not...

best I can help you with is the generic "get you to limping" values.

Check the voltage on the MAF, someone correct me if I'm wrong but I belive it should be around 1.0v.

I had a similar problem it turned out to be the fuel pump, and the fuel pressure regulator, which I found out 200km in the middle of nowhere

Originally Posted by Boxer

Definitely. I'm whacking a pressure tester on it tomorrow to see what's up with it. The only thing though is that not only can that stuff up the mixtures, so can the:

MAF
Intake air temp sensor
Coolant temp sensor
Fuel temp sensor
and probably the LHR door handle if you pull it too fast

I've just been trauling through the workshop manual and while it tells you how to replace all of these parts.... There's no test procedures telling you hot and cold resistances. Back when I was a Ford mechanic, we could test all of these things. Even check vs temperatures using a thermometer etc. All of the figures were in the manuals.

Someone throw me a bone here

Woof woof

Rover 14CUX Hot Wire Mass Flow EFI: Service and Troubleshooting

Fuel injection

If the MAF fails, the only time it will run well is at full throttle,, so hills are no problem,,,

and you thought your fuel economy was bad BEFORE!!!

Originally Posted by Pedro_The_Swift

If the MAF fails, the only time it will run well is at full throttle,, so hills are no problem,,,

and you thought your fuel economy was bad BEFORE!!!

Yep. So I checked the coolant and fuel temp sensors this morning, off the top off my head they we're 3.5 ohms cold and hot the coolant was .07 and the fuel was 1.5. So hazarding a guess, that seems like it'd be right since the coolant gets hotter. I also checked the IAC which works fine and replaced the split fibre washer with an allot one the same width. Then I whacked the A/F meter on it and HOLY CRAP. It was idling at 9.0:1 AF. My mate Dale decided to run it up on the dyno and it didn't get under 12.3, even on cruise. Then out of the blue, it decided it didn't want to be dyno'd. Tell me, since I'm new to LRs, why is this? My car has no ABS, as far as I'm aware the tranfer case is lever operated and the handbrake was off? Doesn't make sense, but then again it is a Disco.

So anyway, I went home, did the rear pads (Bendix no bedding Titanium stripe ones, pretty good), finally pulled the side steps off and continued to do some testing. I thought for a second that I'd try starting it with the MAF unplugged and surprise surprise, it started and ran fine. Fine as far as running rich as buggery. So I figured, yep it's the MAF! So I plugged it back in and went through the tests Westonben mentioned in his post before. The Voltages were as mentioned and everything seems right.

This is the part I need to know that. My CO trim reading was about 3.5V, and as I screwed the adjusted anti clockwise the voltage dropped consistently until it was at .15

Is there a desired voltage? I'm figuring there isn't one and I need to set it up on the AF meter again.

I've done pretty much all there is to do now, so if I can't get this right by the middle of next week, I'll be snipping the injector wires and a spanking new Microtech LT4 is going in. Least that way I'll be abel to tell the engine who's boss, rather than some Pommie computer.