Done a search, and read various threads on power loss from a 200tdi, but didn't see any that describe symptoms that match mine...
1986 LR 90, converted to 200tdi in its past, turbo fitted high up, Defender style. Has run fine since I got it in May 2010, on both normal diesel and bio.
After running on normal diesel for a while, two or three weeks ago, I put bio in, giving a mix of 25/75% diesel/bio. At the same time, it got colder here (SE Scotland), but not so cold that bio should thicken up. However, I noticed the occasional loss of power in top gear at around 50mph. Not a big loss - just a slight lack of oomph on the throttle when trying to overtake on the motorway. I put it down to thickening bio and started filling up with normal diesel to swing the mix back to that.
Since then, things have gradually become worse, even though it's now about 90% normal diesel (and isn't any colder).
Main symptoms...
Before this became evident a few weeks ago, I could happily accelerate up to 60-65 on the motorway without issue. Now, I'm lucky if it can get to 50 (in 5th), after which the power loss thing kicks in until it's had a rest.
I have little experience with diesels and turbos, but have worked on petrol engines over the years. So, I might be missing something that would otherwise be obvious. Suggestions appreciated.
1986 LR 90, converted to 200tdi in its past, turbo fitted high up, Defender style. Has run fine since I got it in May 2010, on both normal diesel and bio.
After running on normal diesel for a while, two or three weeks ago, I put bio in, giving a mix of 25/75% diesel/bio. At the same time, it got colder here (SE Scotland), but not so cold that bio should thicken up. However, I noticed the occasional loss of power in top gear at around 50mph. Not a big loss - just a slight lack of oomph on the throttle when trying to overtake on the motorway. I put it down to thickening bio and started filling up with normal diesel to swing the mix back to that.
Since then, things have gradually become worse, even though it's now about 90% normal diesel (and isn't any colder).
Main symptoms...
- Engine idles fine.
- The turbo seems to whistle normally when I give it throttle.
- Seems to drive okay if I keep the revs low to medium - ie, change up at 10mph in 1st, 20 in 2nd, etc. Feels normal when driving like this - usual low end torque.
- If I boot it to get up to speed or overtake, it suddenly lacks power. This happens in any gear. The power loss isn't 'smooth' - it's as if it's trying to accelerate and can't, and sometimes manages a bit of push before going back to feeble again.
- After it has done the loss of power on booting thing, it lacks power at lower revs as well - I seem to lose the low end torque. For example, it can hardly pull itself along a flat road at 40mph in 5th.
- If I leave it for a bit, the low end torque comes back and I can pootle about normally - until I boot it, and the power loss issue returns.
- If I stop the vehicle when it's in this power loss mode, and give it throttle, it seems to rev up just fine.
- It's as if the power loss is only happening under load (driving on a flat road is 'under load'), and only seems to come in if I have tried to run it in higher revs to accelerate.
Before this became evident a few weeks ago, I could happily accelerate up to 60-65 on the motorway without issue. Now, I'm lucky if it can get to 50 (in 5th), after which the power loss thing kicks in until it's had a rest.
I have little experience with diesels and turbos, but have worked on petrol engines over the years. So, I might be missing something that would otherwise be obvious. Suggestions appreciated.