Thread: Job Done!

Still sounds like the IAC valve, the black smoke is unburnt fuel, Regards Frank.

I think the IAC is working - at least when the engine is hot - it jumps up to 1500 rpm, then drops in steps... 1250......1000.....800 which is what I thought the IAC did.

It's only crawling the revs up when it is cold.

Hi Mattskii
I have just been down the same path with my 98 Disco V8 and also found that the vacuum advance unit was not working so replaced it.Whilst mine would start and run o.k ie no missing or difficult start it was lucky to get 280km on a tank which included highway running.The most irritating problem other than the fuel cost was the irregular idle which would surge and constantly idle high.I suspected the ICV however after I checked some of the threads and eliminated this through some fault finding narrowed it down to the coolant temp sensor or the MAF meter.
I decided to take it to a local Land Rover service centre in Newcastle and let them run some diagnostics rather than throw money at parts hoping to hit the jackpot.I had the car in for a few hours earlier this week and the idle problem is solved ,the fuel consumption looks like it is has improved considerably and the engine feels much more responsive under all conditions.The 2 problems they found was the MAF adjustment was way out (running a rich mixture) and the coolant sensor also reading low so the engine was again running a richer mixture than required.
The MAF was reset and the faulty sensor replaced.The cost was significantly less than replacement of the MAF and ICV and I have the piece of mind knowing that everthing else has been eliminated as a possible cause.
I guess the message here is that you can go so far with some problems until you reach the point where some specialised diagnostics are required to ensure that you find the root cause of the problem which can be a fairly cheap fix.The alternative can be a lot of time and money p***** away on parts in the shed at home and still not find the problem.
Dont get me wrong I enjoy the challenge of fixing things and have had a lot of wins on the beast so far but it may be worth looking up a good LR mechanic in your area and taking the car in for a look.
Good luck

temp sensor is a good thing to check, i had similar problem long time ago.
also check the stepper motor, at the back of the plenum, unscrew it and wack some carby cleaner through it and down the hole where it came from

Melbourne's very big, so give us a hint about your general area and perhaps we can line you up with an experienced fettler to solve your problem.

Pete

Hi guys,

Sort of been round this loop, the tests I have done so far:

Fuel Temp when engine cold = 2640 ohms = 20"c - about ambient
Fuel temp after a short drive = 536 ohms = 60"c

Coolant cold = 2610 ohms = about 20"c - ambient
collant hot = 269 ohms = about 90"c

With thanks to Dave (Cheers) set the MAF output to 1.3v with just ignition on. We also set the timing to approx 9" BTDC

Cleaned the MAF and the hotwire.

Checked the 2 loops on the IAC stepper motor both in range (51.4 and 51.2 ohms) - removed and gave it a jolly good clean!

Rechecked all these values at the connector plug on the ECU to rule out any wiring faults and got good values.

Checked the 2 injector banks from the ECU plug Right bank was 4.2 ohms so in range, left bank is 4.7 so slightly high. Possibly correlated to the injector in cylinder 1 which may be weeping a bit - the spark plug is damp.

After doing all this the car went from taking forever to start, turning over for ages and only firing with input from the throttle to what I described earlier in this thread, which was a great improvement.

There are more tests I could perform, but I have reached the limit of my knowledge (Which was 0 when I got the car! Thanks to this forum I have been able to do the above work) I have also run out of tools - (I realy need to borrow a fuel pressure guage) There are also a reem of other test I have in a document here (Thanks Phillip) but I am struggling to understand exactly what they all are, and where all the components are on the car.

I think, by the state of the carbon on the plugs I should replace the fuel injectors, but I am a bit short on funds at the moment. Plus this is a major job which I'll need to psyche myself up for, being that I never done anything with a motor before.

Keep plugging away at it, at least your getting to know the car. It may not just be one thing but a combination. Just keep working through it and hopefully you will get on top of it.

As I said on the day I'm no expert on the fuel side of things and did not have any test equipment to test it. This is where I handed mine over to a Landrover mechanic to check it for me when mine would not start and was flooding. It turned out my return fuel line to the tank was blocked causing fuel to leak through the injectors. It was unblocked and the fuel pressure regulator replaced. Also the Fuel pump was a bit lazy and was replaced.

It did not cost me a great deal to have the experts look at it and it was good to get it going at the end of the day.

We covered most of the tune bit and swapped some of my spares it try and locate the issues. It was idling quite nicely that the end of the day, but it had also warmed up by that point.

The things we covered were:

Cleaned the MAF hot wire and adjusted to 1.3v,
Cleaned the TPS,
Cleaned the blocked T Piece from the Pleneum chamber to the PCV?
Set the timing to 9 deg ( you could not even see the timing marks previously,
The stepper motor you had cleaned.
Checked Vac Advance and confirmed stuffed.

Hope you can get on top of it soon so you can get out and enjoy you car.

Hi,

Yup, I have covered most of what you covered. I think I should get someone to look at mine, but I have had no work for a week, and finances are dire, so it will have to wait.

Odd thing is, since all the work, and the new vac advace, it has been starting pretty well every day, from cold. But it is now not starting from hot - it was the other way round before! lol So something has changed, but I can't figure out what.

Hopefully I will get some more work over the next few weeks, then I will consider taking it to a mechanic.

Any reccomendations for a good, trustable mech in North Melbourne anyone?