I've gone through the threads, searched the internet, read the manuals, and replaced parts and still having issues.
Here's my vehicle:
Land Rover Discovery I
Engine: 3.9 V8 Petrol
* British Spec, right hand drive.
I bought it off a local that was going to part it out but decided not to since it was in such great condition...and it is. I looked in the records and found that the last dealer service was back in 2004 when it had about 62,000 miles on it. So that means for the last 6 years its only been driven 12,000 miles. I drove it for about a week and then started having issues.
What it is doing:
I start it up and drive away...almost immediately when I hit the accelerator it kind of lags in power and almost stalls. To keep it running I've found that I can keep my foot on the gas and brake or drop it to neutral as required as I decrease in speed, usually keeping RPMs around 2-3000. This will prevent the stalling while I'm driving.
However, when I stop and let my foot off the gas then it will stall and won't start up again. Cranks, but no starting...at least until I let it set for awhile.
After about 15-20 minutes, I have to keep pumping the gas pedal until I can coax it to start...sometimes it will, sometimes it won't. All the issues are very intermittent and I have not noticed a difference when its hot or cold outside. Although time that the vehicle is running is sometimes a factor. However sometimes it is difficult to start cold, but will still start none the less. It is after its been running and I turn it off that the not starting is often the problem.
I just tried this today: Started engine, no problem. Let idle for a couple minutes then hit accelerator a couple times to see if the idle would fluctuate, it didn't. Then I put it in drive, rpms fall as they should, but as soon as I hit the gas, it hesitated and rpms drop. It chugged a bit and I got moving. I let it idle down the street a bit and as soon as I would hit the gas though, it would hesitate and almost want to stall. I continued on doing the accelerator/brake method to keep rpms up while driving to get it up to normal operating temp. Got back, turned it off and it cranked right back up. However there is hesitation on hitting the gas pedal. Hmmm....
My initial guess, fuel or ignition problem. I heard of the crankshaft position sensor going bad...however, this vehicle does not have one (according to the dealer and I've looked all over for it).
So this is what I've replaced so far:
- Plugs and Leads
- Fuel Pump
- Fuel Filter
- Mass Air Flow Sensor (MAF)
> I spoke with a local dealer that uses Auto Logic for diagnostics and they said that AL is very limited to the codes it will read and is unlikely to pick up the engine codes. Anyone ever hear of that?
> Check engine light illuminates for a millisecond during the lamp test and then shuts off...it seems it would stay on longer, most of the time I miss it coming on its so fast. However, it has never lit up at anytime.
> Fuel Pressure check is approx. 2.3 bar at the fuel rail which is normal according to the manual.
> The fuel pump always turns on whenever I go to start the vehicle, even when it just sits there and cranks but does not turn over.
Here's what I'm going to try next:
> Compression check
> Fuel Temperature Gauge
> Throttle positioning sensor
Any comments/recommendations? This is getting kind of expensive.
On a side note, I do get some blue exhaust while idling and occassionally while driving. I've heard valve stem seals are often an issue and I didn't think it would be related, but I'm adding it in here just in case. Also, the midsection of the exhaust has a hole in it.