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I have a 59 plate 1.6 TDCi Duratorq engine focus, owned from 2010 (9K) to now (115k) and serviced on time at a main dealer.
I'm getting P0299 code (underboost) whenever I floor the accelerator.
No problems if I take it easy.
I changed the fuel filter a few months back, after this code came up and it was fine for a while until now.
Yesterday I took the EGR valve off and cleaned it as there was a 'stuck EGR valve' code coming up. This now seems ok, but I am still getting 'Underboost'.
I cleaned the MAF and I've looked over all the induction pipes, checking for splits. None found.
I'd had a DPF sensor pipe leak but this is fixed now too.
Reading a lot of posts on the net, it seems that the 1.6 turbo's have a flaw and the bearings may be on they way out, due to the oil supply pipe filters getting blocked with gunge. At very expensive job to repair as the turbo needs replacing and the engine needs cleaning internally to get rid of any gunk.
Before going down that route, anything else worth checking?
The turbo actuator is moving up and down all time while on idle, it moves slowly up then jumps back and repeats.
The turbo seems to spin ok, it doesn't freewheel much if you give it a spin and there is a slight bit of play in the shaft which you can just feel when moving it.
I have a decent OBD scanner which can record nearly every sensor on the car, so I wondered if recording the MAP, MAF, RPM, fuel pressure, Throttle while driving and accelerating to get the fault up, would show me anything useful? Not sure where I'd find out what these should read on a 100% working car?
I noticed that the turbo actuator was moving about all the time while the engine was idling.
Looking at the ODB logs, the drive to the actuator, VGTDC was not moving much. However the MAP was ramping up and down every 10 seconds. This matched exactly the movements in the actuator.
My theory was that there was a vacuum leak which allowed the actuator to gradually sink back. The ECU applies a puff of vacuum every 10 seconds and this makes the actuator jump back again.
Well today I tested the boost control actuator.
I attached a pipe to the vacuum actuator on the turbo and stuck a syringe on the other end. Pulling the syringe creates a vacuum and the actuator moves and stays put.
So it works fine and hold vacuum.
I then went looking for the control solenoid. Some people call this the boost control solenoid but the supplier and Ford call it a Pressure Converter Valve.
It located behind the engine on the drivers side, low down, just above the steering rack.
See pic.
To get to it, you need to take the under cover off (6 or 8 screws). then get right under the car and look up past the steering rack. The valve has a 2 wire connector and 3 pipes on it.
The pipes are from the left, vent (to the small air filter on the end of a pipe at the back of the engine bay, just under the wipers), vacuum out to the actuator and vacuum in from the vacuum pump via a reservoir.
It's easy to get off once you get access to it.
I made a fork shaped pipe puller to avoid damage to the rubber pipes. It slips over the tube and pulls the rubber hose off.
I tested the valve with a syringe and some pipe and it leaked air.
So I bought a new valve. Ford charge £125 for these. They are on ebay for £45 but I decided to go with Eurocarparts (and get a warranty). It was £64, but I had to buy one for a Citroen as they didn't list the Ford one! The valve is the same and it's made by Pierburg part code 7.00968.03
I want to thank you for your post . I have the same car Ford Focus 1.6 tdci 2010 with the same problems .
After reading your post I fixed the car.
You saved me money and time ,thank you again.
With faitfully Marcel.
I want to thank you for your post . I have the same car Ford Focus 1.6 tdci 2010 with the same problems .
After reading your post I fixed the car.
You saved me money and time ,thank you again.
With faitfully Marcel.
Hi Marcel, No problem! I am glad to have helped someone save some money and get their Ford going again!
With all the turbo bearing issues, it is great to have an easy fix.
im having the exact same issue after driving my car home! up the motorway turbo kicked in then eng mgnt light then no boost in 4th.
great round the doors but soon as im out need to hit 4th it does it again. the eng mgnt light is stuck on code p02099
en engine malfunction on the screen
i have a 2009 1.6 tdci titanium with 78000 on the clock
the solenoid is brand new
all hoses are split free
i have noticed a slight oil leak at the side of the oil feeder from under the copper washers would this cause p0299?
Further to this issue I have a very similar issue
Can anybody help. I have had a similar issues with P0299 and P1103 errors. They clear every time I reset I erase with my tester . I tend to get the limp function kick in at around 2000-2500 revs in 4th gear.
I have put a new vacuum solenoid valve on, check the vacuum pipes and the vacuum valve holds in position on the turbo at idle.
I checked the voltages on the MAF sensor. So I checked the main 12v (14.2 v running) positive and negative and then checked across the sensor wires where I'm getting 7.12 volts at idle and 7.6 volts at 3000 revs.
Are these values correct or is there an issue here.
What others things can I check.
@richardindorset I am unsure if I am having the same issue as you diagnosed. I also get the p0299 underboot, however I don't have access to a garage right now, but I could log some stats. It seems to me that my VGTDC stays low after it logs the p0299 underboost DTC. Did you notice anything like that?
My car is a 08' 90hp focus mk2 1.6tdci. Normally when driving a turbo diesel, you can kind of feel when the turbo kicks in at around 2500rpm ish (give or take the model), however I newer ever recollect having had that feel in this 90hp focus. It has the same flat sluggish acceleration all the way up to 120km/t (75mph)
The PIDs that is shown in the graph
Acceleration onto the freeway.
Notice how the VGTDC (orange) newer seems to rise after the DTC (P0299 underboost) is logged, even though the speeder (APP,% cyan) is floored before and after. By coincidence the DTC is logged during the gear change from 2nd to 3rd,
Hi, I am a diy car mechanic and I am repairing a FF 1.6 tdci mk2 2009.
I have a question about the vacuum hoses(3) which originate from the turbo pressure valve underneath the engine.
The right hose goes to the vacuum container
The middle hose goes to the turbo
But I dont know where the left hose goes.
Can you please help me out with this problem.
Best regards,
Many thanks for this thread. It saved me I'm guessing many hundreds of pounds taking the focus into a ford dealer.After checking that the turbo was obviously not lunched I just plugged in the ODBII logger and saw low MAP, replaced the actuator and hey presto car back to normal for £45.
I replaced the boost control valve and still have the problem? What more could i check/do to fix this issue! It is so annoying! Have no obvious boost leaks and have no idea what to do next
Many thanks for this thread. It saved me I'm guessing many hundreds of pounds taking the focus into a ford dealer.After checking that the turbo was obviously not lunched I just plugged in the ODBII logger and saw low MAP, replaced the actuator and hey presto car back to normal for £45.
i replaced the boost control solenoid and still have the problem. Just coming up as underboost could this be the actuator and is it the same problem as what you had? Should i replace my actuator and see if this fixes the problem?
Amazing post, spent the last 6 years trying to solve the same problems on long journeys, tried new fuel filters, cleaning out fuel tank, cleaning maf sensor(several times!) new air filters, replaced turbo rubber gator to air filter, all to no avail.. This seems to have cured it, actuator was bouncing up and down a few mm before I changed the part then was solid afterwards, taken car on a long blast and so far no limp mode! Hurahh! Thank you!!!
I noticed that the turbo actuator was moving about all the time while the engine was idling.
Looking at the ODB logs, the drive to the actuator, VGTDC was not moving much. However the MAP was ramping up and down every 10 seconds. This matched exactly the movements in the actuator.
My theory was that there was a vacuum leak which allowed the actuator to gradually sink back. The ECU applies a puff of vacuum every 10 seconds and this makes the actuator jump back again.
Well today I tested the boost control actuator.
I attached a pipe to the vacuum actuator on the turbo and stuck a syringe on the other end. Pulling the syringe creates a vacuum and the actuator moves and stays put.
So it works fine and hold vacuum.
I then went looking for the control solenoid. Some people call this the boost control solenoid but the supplier and Ford call it a Pressure Converter Valve.
It located behind the engine on the drivers side, low down, just above the steering rack.
See pic.
To get to it, you need to take the under cover off (6 or 8 screws). then get right under the car and look up past the steering rack. The valve has a 2 wire connector and 3 pipes on it.
The pipes are from the left, vent (to the small air filter on the end of a pipe at the back of the engine bay, just under the wipers), vacuum out to the actuator and vacuum in from the vacuum pump via a reservoir.
It's easy to get off once you get access to it.
I made a fork shaped pipe puller to avoid damage to the rubber pipes. It slips over the tube and pulls the rubber hose off.
I tested the valve with a syringe and some pipe and it leaked air.
So I bought a new valve. Ford charge £125 for these. They are on ebay for £45 but I decided to go with Eurocarparts (and get a warranty). It was £64, but I had to buy one for a Citroen as they didn't list the Ford one! The valve is the same and it's made by Pierburg part code 7.00968.03
So I stuck the new valve on and hey presto, no more turbo actuator movement on idle and no MAP changes when idling.
Out on the road I have full boost in all gears and the car goes like a rocket!
So before getting your turbo replaced, check what the MAP is doing on idle and what the actuator is doing too.
My Ford Focus 1.6tdci 2010 Estate was showing the engine management light and the engine was juddery.
I use Carista app and dongle to read the codes and had P0299 and P1103 showing.
Did lots of googling and was about to order a new MAF SENSOR first then maybe a turbo, then I can across your post. On a whim I order the part you mentioned (https://www.ebay.co.uk/itm/Ford-Focu...72.m2749.l2649)
Fitted it last night and it seemed to have worked! Cleared the codes and re scanned and all is fine, car drives normal again. Whilst I had the the under tray off I gave the car an oil change too.
My Ford Focus 1.6tdci 2010 Estate was showing the engine management light and the engine was juddery.
I use Carista app and dongle to read the codes and had P0299 and P1103 showing.
Did lots of googling and was about to order a new MAF SENSOR first then maybe a turbo, then I can across your post. On a whim I order the part you mentioned (https://www.ebay.co.uk/itm/Ford-Focu...72.m2749.l2649)
Fitted it last night and it seemed to have worked! Cleared the codes and re scanned and all is fine, car drives normal again. Whilst I had the the under tray off I gave the car an oil change too.
So thank you very much!
Glad to hear it worked!
My Focus decided to die today, so new post incomming...
I recently bought a 08 plate Focus 1.6 TDCi from a friend of mine. It was leaking on the injectors and I've fixed it. Interestingly, after I did so, the car seems to be sluggish. I remember when I drove it home first time, the turbo was whining quite loudly (I knew that's gonna be my next job) but the car was pulling well. Once I fixed the injectors and cleaned the engine, I couldn't hear the turbo as I used to do, and I noticed the power loss. I also noticed that the actuator isn't moving at all. I decided to replace the turbo cartridge (only £62). Using this opportunity I cleaned and polished the variable geometry vanes, so everything is moving smoothly. After I refitted the turbo, there was still no movement of the actuator. I checked the actuator itself, it is holding the vacuum and is moving smoothly. I removed the boost valve and checked the power supply with the multimeter. It seems to show 8.3V, then goes up to 10.3V within 10s and then stays at that level even when accelerated. then it dies roughly within 15s after the engine is stopped. At this point I noticed, that I am unable to rev the engine over 3000rpm, it is cutting off. I had no faults on the basic scanner, haven't had a chance to perform a scan with FORScan yet. The boost valve keeps the vacuum, I will check whether it works at all later on, but I could imagine that the voltage should be variable to make it work actually and it's not happening currently, it's stable at 10.3V across the revs.
Any suggestions at this stage guys? I would appreciate your help.
One more thing - I spoke with the previous car owner (and I trust him, as we work together and know each other for 15+ years). He said that the vehicle used to be quite nippy and never experienced any power loss. This really confirms my words, that I had it running well on the way back home when purchased the vehicle. I guess this might be related then to the work I've done so far... I checked the vacuum pipes and all the plugs, everything seems to be OK. I also disconnected the air filter pipe for a minute to see the turbo spinning, so there shouldn't be any restrictions in the intake system (new air filter fitted anyway).
Anybody knows, what reading should I have on the power supply to the solenoid?
I'll appreciate your help!
22-02-2017, 09:34 AM
P0299 code (underboost) 1.6 TDCi 2009
