Hi, The Mercedes dealer tested the fuel pressure at the inlet rail, and replaced the submersible pump in the tank, and whilst recently a new fuel filter was fitted, it was replaced again.
The erg valve isn't vacuum operated and has been cleaned and tested 3 times.
The turbo isn't vacuum operated, only by actuator and nozzle.
When the car was first dismantled 3/4 years ago, it was sent to a specialist reconditioner who changed the compression chamber - damaged in the accident, fitted new bearings/seals, and dyno balanced it. When the scanner picked up high and low boost pressure it was sent back to the turbo co. who now say the nozzle was set to high, so they adjusted it, tested the actuator again - ok, and we refitted it. The high boost is now rectified, but the low still exists. An intercooler pipe has been replaced and the intercooler rinsed just in case of a blockage - ok.
Also the MAF meter has been replaced just in case, without effect.
I see that the glow plug light has started to appear pre start, where previously unseen, and the car has improved.
The fuel has had a good dose of dipotane without effect, and the injectors are given as good by the star diagnostics.
Until recently and esp. when cold the car would lack power, make a whooshing noise, then 'pink' and emit a cloud of noticeable smoke, before clearing, but this has now improved. The dealer tried the engine with the exhaust disconnected without success and says he believes the cat and dpf are ok.
The main indicators I experience are - significantly worse when cold, and secondly at no point has the second half of the throttle been effective so the car often struggles when under load (on hills), but the recent resumption of a glow plug light has improved the drivability at present.
Having now spent nearly £2K trying to resolve this issue I'm reticent to spend more without a strong indicator. The management light is still on caused by low boost fault code, although it hasn't been cleared this week
I don't believe it has one, just the turbo with a plate bolted to the lower end which holds the actuator with a rod that connects to the nozzle
The turbo and actuator were tested a flow adjusted only 3 weeks ago
I would be pleased to wait a short while
When the car had all the repairs to the front offside completed (the impact was in the air box area and was hard enough to need a car bench to slightly realign the f/o/s strut mounting and straighten the inner wing forward of this) The impact pushed into the turbo compression chamber, and the unit was sent to Turbo Charger Services, Huddersfield who straightened the impeller shaft, replaced bearings/seals and dyno balanced it. Everything else in this area was replaced. As the car had been dismantled there were a number of fault codes, most of which were cleared, but initially we were left with high and low boost. Following a visit to MB dealer the turbo was removed and sent back to specialist who adjusted the flow rate at the nozzle, and since which has now left us with low boost only, and the issues as previously mentioned. Today the car had a bad issue - when restarting after being left for 2 or 3 hours. I drove away with little progress and it smoked badly, rattled and made an even louder whooshing sound, but eventually once stopped at a junction cleared and pulled away ok, without the sound rattling or smoke. The other issue is mostly there is now lower half of the throttle resting at all. I spoke to the MB tech yesterday as I was hoping the car had inlet flaps on a spindle which might have been sticking due to a build up but he says this car doesn't have that type of set up - bugger! He did notice that the outlet pipe from the intercooler and the charge tube to the turbo were not fully seated (probably due to the excessive high boost until adjusted) so I need to attend to this. The fuel consumption is deteriorating day on day, I'm now down to around 20 mpg. I will get the codes if needed.
Do you need the fault codes before responding?
The codes are concerning charge boost pressure
The high boost has now been rectified by adjusting the nozzle to where it should be? I am awaiting reply from Turbo Charger Services, Huddersfield who carried out the initial repair and recent nozzle adjustment
If I need another turbo do I go for a used one or a recon. either way there is little chance of knowing how good they are, and its a days work to change it.
Turbo repairers agree that the symptoms are in line with vane mechanisms, but are puzzled as they adjusted them and didn't see this problem when flow testing. I will give them the OE number of the turbo and they will build up another, I can't see any alternative. I have insisted they use completely different turbo parts for the next one, we don't want to use an unknown defective casting or other usual rebuildable part.
I did some specific road testing today. When the engine is running fine it will not rev past (exactly) 3000 rpm. Stop the car and rev it while stationary and it will rev to its full rpm - 4750, but with smoke etc.
Once pulled away it will revert to the lower rpm, once it has made the loud whooshing sound and cleared its throat. This is a constant when hot.
I don't think any of these rebuild companies have used stock kicking about, they either have rebuilt units, but mostly rebuild yours. I did ask a couple but they declined.
Once I resolve this issue I will have the ecu remapped, but it might exacipate the existing prob?
The turbo company have accessed a replacement turbo, which they have rebuilt and tested, and will supply at cost. It will be a complete unit with actuator so no parts will be reused from the original. When available we will get it fitted and see if matters improve, meanwhile I hear that there is a local company dealing with electronic diagnostics and I will approach a guy I know who may be working there shortly, and see if they are set up to deal with a problem ecu.
The turbo is only costing £150 and a friend is fitting it in his workshop, so I'm willing to pay this to rule out or in the turbo.
I have twice contacted a remapping dealer who hasn't replied again. They use Quantum Tuning software, and I have recently been given 2 others - torquetothedevil and emerald. So I will give it another go and see what they say. Thank you for your ongoing advice
I,m following your suggested course, we have cleared the fault codes since the air mass meter was changed and we now have 2025 and 2359, the latter being the ever present low boost pressure.
We have a completely rebuilt turbo ready to fit, but I have now spoken to a remapping agent who are also general repairers. So before we change the turbo I'll follow this path.
They seem confident that they can resolve these issues.
I'll let you know
Car is still at remapping garage, who haven't had to much time yet to fully investigate, but currently say it looks like a lack of air, and might be inlet manifold issues. Should hear more soon. Will let you know
Hi, After 3 weeks the current garage can't find the prob, but they are sure its a mechanical prob not electronic, so to rule out it being the turbo, they are fitting a completely different rebuilt turbo I have supplied. Fingers crossed
The saga seems to go on and on.
Since they fitted the rebuilt turbo, (just in case), they have checked all the exhaust and remapped the inlet, and are now having the injectors tested. Will I ever get the darn thing back, and at what cost, I don't know
The reply this morning is "we are at Bosch (injectors) now going through readings. The only fault presenting is a low reading on the MAF but no fault codes stored, will report back when have some news"
I am being asked if the turbo actuator was adjusted to suit the turbo, so I assume the injectors are ok.
The rebuilt turbo which has now been fitted (as supplied by me) has no parts from the cars original. Docs supplied by Turbo Charger Services to show vibration sorting rig results = passed and a flow test showing temp and pressure, all of which passed. Does this mean the actuator has been coded/adjusted to suit the turbo. If not is it only the MB star diagnostics which can then carry out this task? because the turbo was removed and another actuator fitted when the car was with my MB dealer some time ago, and he showed me him operating the actuator via their system to show it was operating ok.
After all these months and several turbo tests/rebuilds it has been proven by the turbo charger company that they did not set up the parameters properly. They acquired new equipment and the problem is resolved.
I have informed them that I will be making a significant claim for their ineptitude. The remapping did not per sa resolve but confirmed a good ecu and the subsequent definitive problem.
Many thanks for your protracted efforts