Loss of power (RPM drops) but no codes?

Hi folks,

I'm trying to help my friend who has a 2003 Freelander 2.0 ES (Diesel).

Symptoms:
When driving along a motorway, there's a loss of engine power (RPMs drop) and the check-engine light comes on. Also happens at low-speed but less noticeable. It only happens briefly and then power comes back - but it's becoming more frequent.

So far:
It's been brought in to an independent mechanic and they reproduced the problem but are unable to read any codes from it. They've even reproduced the problem while the scanner was connected to it! (so I presume this was done while at idle!). But they haven't been able to diagnose the problem, so presumably it's nothing obvious?

Unfortunately all Land Rover dealers are booked up and they can't look at it until the New Year! :doh:

Any ideas?

Many thanks!

Hugh

Low fuel pressure.
When was it last serviced and has it had the fuel filter renewed?
If it's done around 80k or more then the LP pump usually fails sometime after that mileage.

Use the 'search this forum' there should be similar posts.

only other possibility is the boost control solenoid on the way out

Overboost,get it checked as live data.If it was low fuel pressure there would be a code logged,plus poor starting.

Thanks for the replies so far!

Some more info: it has done almost 100K and was serviced about a month ago (after which this problem started!). I've asked my friend to get the receipts and service history to see what work has been done on it (will update again as soon as I have that info!)

I also checked the black rubber air pipe across the front of the engine and it seems fine (recommended to check on other forum).

It never has any trouble starting so that sounds like from the posts above and reading on this forum that this would rule out the low-pressure fuel pump? However it also sounds like this is a component that is likely to go, so might be a good idea to replace it soon or start by giving it a clean?:
http://www.landyzone.co.uk/lz/f38/freelander-how-clean-your-fuel-pump-52118.html


That leaves:
- Overboost
- Boost control solenoid

Would either of these be the source if the mechanics reproduced the problem while idling?

Many thanks,

Hugh

It can still start OK with a dying low pressure fuel pump, the first sign of trouble is often that it can't keep up with high demand on motorway or hills.

As said though get it on diagnostics that can read live data and then you can check/watch the boost reading from the map sensor and go from there.

Hey folks,

Thanks for your help on this. Unfortunately I didn't have a way of reading live data. Took it to the dealership last Friday, here is what they wrote:

"Rectify shuddering and cutting out. Interrogated fault memory. Fault present regarding fuel pressure. Checked pump pressure. All okay. Inspected wiring and connections. Faulty connection found at fuel pressure sensor. Cleaned, fixed & re-assembled. CL&L."

So appears there was a fault code after all! But the previous mechanics weren't able to read it - probably wrong equipment? :-(

Do you guys have any recommendation for a code reader for future reference?

Thanks!

Hugh