2004 T4 Diesel Turbo Transporter losing power.

[Macca64]

Hi all
I have the aformentioned van. Its been very reliable for the last year but just lately it suddenly loses power, doesnt miss or blow smoke when it happens, i can barely get over 80kmh on a flat road. It almost feels as if its in limp mode. Stopping the vehicle and restarting it fixes the problem and it runs fine, but i have to do this at least 3 or 4 times on 100klm journey, not to the mention the embarrassment of trying to get it up hills while its doing it. I know it could be a multitude of things i need to check, i just didnt want to go down the rabbit hole till ive tried to find someone else this has happened to that might shed some insight. Has had a new fuel filter fitted within the last 12 months. And the EGR was disabled when i bought it.
Thnx in advance for any help

[jets]

When I bought my first T4 in NSW, I knew it didn't have the proper power but on the level it wasn't too bad but on any type of slope it was very slow & held up the traffic. As soon as I arrived home, I took it to the dealer who thought it could be a faulty air mass meter. I bought a Bosch replacement, a few minutes to install & full power was restored. I have since learned that if you unplug the cable & normal power is restored it's a very good chance that you have a faulty air mass meter.
Now this doesn't mean that you can drive around without replacing it as you will have other problems EG possible high fuel consumption.

[Rebuild]

lots of things can cause limp mode. If you can get a code reader on it, it may help with troubleshooting

[BrianJ]

My T5 was occasionally going into limp, and it had no error codes or alarms showing, and it ended up being caused by the auto gearbox controller. Resetting the controller fixed it completely. Never rule out anything.

[Greg Roles]

Is in an auto and are all the numbers highlighted?? Could very well be trans limiting the power.

Like already said you need to scan it, even with a generic OBD reader and narrow down the vast range of things it could be. Autobarn and Supercheap, as well as most tyre/mechanical shops have scanners for a fee if you don't have anything....

[Macca64]

forgot to mention....its manual and ive recently replaced the mass air flow sensor.

[jets]

Another thing that others mention is a faulty relay, I think it maybe no 30. Ignition switches also wear out on T4s but this wouldn't explain lack of power.

[Sunny43.5]

My son had the diesel T4 as his first drive , yes it was embarrasing on the open road if you tried to pass people , I ended up buy another T4 on Ebay for $3000 with the 2.5 Petrol engine and did a complete transplant of the engine gearbox exhaust fuel system electrics and he was very happy . I put the old slug diesel into the Ebay van tidied it up and sold it back on Ebay for $4000 nice !

[Greg Roles]

There are low power versions of the 2.5 engine, used in the T4 mainly, and they started at 65kw!!