Question-------------------------
Followup To
Question -
Disco 1 98 V8 3.9... My Disco had been parked up for a week. I decided to top up the fuel ready for a weeks journey. While I was travelling back home from the petrol station the car started to hesitate. I checked all the connections and all were fine. I had changed all spark plugs, correctly gapped, coil, leads, rotor arm and dissy cap a month before, all was fine then. During my week away the car still hesitated and on a couple of times nearly stalled at junctions. When I returned home I took it in to Land Rover for a diognostic test. They told me the Air flow meter was at fault and I had a cracked O/S manifold. I changed these items, but I now cannot start the car. When I try to start the car I smell fuel and on looking at the spark plugs they are a bit black, although I have a good spark on testing them. It takes me about half an hour to start it and when it does fire up its rough and struggles to keep going. Due to the price of the Air flow Meter £344.00 + £49 Diognostic + £175.00 Manifold, I am reluctant to send it back to Land Rover, They wanted to charge me around £800.00 to do these pointless corrections. Is it possible for you to perhaps guide me in to another fault finding solution? Oh' I have also renewed the Oxygen Sensors as they were due for a change.Another week has gone by and I still cannot find the problem. Kind Regards Marie
Answer -
Hi Marie,
the problem you describe is usually associated with the MAF. The MAF controls the air that is mixed with the fuel and when it fails, the signs are misfires, stalls, and too rich a burn - too much fuel not enough air.
You could take the MAF back to the dealer and tell them that its not working. IF they did the work, it should be covered under a 30 or 45 day garantee (standard policy over here). If you did the work, remove the MAF and have them test it out. I don't think its working.
If you did all this work, that's impressive. But I have one comment...
As a software developer, I often am faced with program problems. When solving these problems, I focus on each one and carefully move from identification to problem resolution. If a software updated is needed, I wait until the 'bugs' are fixed...unless the update is the fix.
In your case, you've replaced quite a lot of parts. You addressed a problem and, according to what I understand, fixed a problem involving the MAF. If you did all this yourself, its quite impressive. I would have suggested that you leave the O2 sensors out UNTIL the problem with the hesitations/stalls were repaired. Now that you are having problems after the installs, you're in position that is compounde by not knowing which part to blame. Is it the MAF, the O2 sensors or something else.
I would have addressed the MAF related problem first and then, when running ok...change the O2 sensors. That way, I'd know that MAF was working (or not) and then install the O2 sensors. If they fail, you'd know it soon enough.
So...its either the MAF or it could be another component.
Best of luck,
JohnMc
Hi JohnMc
Thank you for you guidance >>>>>>>>>
I enjoy mechanical repairs, im not afraid of getting my girlie hands oily, hence, doing the work myself, 'he he'...
I also have an old series 111 which I can maintain easily. Its the Discovery that mystifies me, ( New techno ).
Parts changed previous to air flow meter, were due,
according to landrover....
The o2 sensors were changed after the new air flow meter had been fitted. Reason for changing o2 sensors, 20,000 miles over due.
The car starts now ( smile ) but still hesitates and sounds rough at idle, with or without the new or old meter.
For the none start... 2 leads the wrong way round, my error... Never mind..
The new air flow meter works fine, its been tested. Would there be another helpful suggestion for me concerning the hesitation?
I would like to point out that once driving it still has all its power.
Kind regards
Marie
AnswerMaire,
I'm glad you can get your hands dirty maintaining your Disco. I'm sure you've save loads of cash doing the work yourself.
Concerning your Disco's hesitation problem, have you considered that you may have a vacuum leak? This could cause some hesitation and even stalling the engine. Check the hoses and inlet manifold.
There could also be a fault within the fuel injection system. Have you had them cleaned lately?
With all the changes you've made, do you still have wet spark plugs?
Regards,
JohnMc
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One other thought: idle air control valve IAC valve stepper motor faults. The Throttle Position Sensor TPS, engine load (MAP, A/C compressor, power steering pressure, gear selection, etc.), battery voltage and engine coolant temperature all have an affect on the IAC.
That's about all I can think of.
Regards,
JohnMc
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