Peugeot 307 2.0 HDi 110 - Peugeot 307 2.0 HDi 110 down on power - UJU

Hi everyone. Sorry to keep banging on about this but I'm still having problems with my car, its stuggish until the turbo kicks in. I bought the car in December and have been tinkering with it since trying to solve the problem. So far I have replaced the MAF, MAP sensor on the intercooler, air filter, oil filter and oil and cleaned out the DPF. All of this has improved the performance but its still slow! I'm all out of ideas now, has anyone else got any suggestions? I have a Peugeot planet diagnostic and the engine is no longer reporting any faults, is there anything I can test using the diagnostic?

Peugeot 307 2.0 HDi 110 - Peugeot 307 2.0 HDi 110 down on power - unthrottled

I'm sure you've checked, but is the wastegate actually closing properly?! Are the intercooler and hoses leaktight-leaks in hoses are really hard to spot because you won't see/hear anything until the pressure starts to build up. They aren't perky engines to begin with!

Peugeot 307 2.0 HDi 110 - Peugeot 307 2.0 HDi 110 down on power - UJU

I'm sure you've checked, but is the wastegate actually closing properly?! Are the intercooler and hoses leaktight-leaks in hoses are really hard to spot because you won't see/hear anything until the pressure starts to build up. They aren't perky engines to begin with!

Thanks for your help. No I haven't checked the waste gate, how should it check it? There is a suspect pipe from the turbo to intercooler which is oily. The only reason I havent looked into this further is because surely a leaky intercooler pipe would have the opposite effect on the engine. Small power loss at low revs (when turbo boost is low) and high power loss at high revs (when turbo boost is higher). Its the opposite on my car, low power until the turbo kicks in. Please correct me if im wrong. And yes I agree, its a diesel at the end of the day but surely the HDi 110 should be more powerful than my old HDi 90 lol, or have peugeot fiddled me?

Peugeot 307 2.0 HDi 110 - Peugeot 307 2.0 HDi 110 down on power - unthrottled

Small power loss at low revs (when turbo boost is low) and high power loss at high revs (when turbo boost is higher). Its the opposite on my car, low power until the turbo kicks in.

No!

Turbos don't work on RPM except at very low engine speed when there is insufficient exhaust gas to drive the turbo properly.From about 2000 RPM onwards boost is essentially constant-but the air flow isn't. That means that a fixed volume leak is much more noticeable at low engine speed than high engine speed where the airflow from the turbo is small compared to the leak. The 'leak' clearly won't make any difference at idle when the pressure upstream of the turbo is the same as the ambient pressure outside. This is why leaks are hard to find.

Checking the wastegate: You need to check the actuator to make sure it isn't stuck. I don't know if you have a pneumatic or electronic N75 valve.

You can carry out a fairly easy test to check for an intercooler leak. Disconnect the exit from the turbo and manually throttle the pipe with your hand. This will create a pressure drop so uif there is a leak it will start hissing.

It's normal for the oil seal to leak a little oil-but an excessive amount of oil in the intercooler indicates an oil seal failure-which needs addressing. Is the turbo noisy?

Peugeot 307 2.0 HDi 110 - Peugeot 307 2.0 HDi 110 down on power - ianjoh

Difficult to diagnose yours but here is my experiance.

I have recently suffered a gradual loss of power on my 406 Hdi 110 with an increase of 'limp mode' when ragging it. A change of MAF meter made little difference.

I could see the turbo was not doing much when I revved it as the intercooler pipe was not expanding. On mine the turbo is controlled by a solenoid that regulates the vacuum applied to the variable vane actuator, this soleniod is mounted on the bulkhead next to another that controls the EGR. As a check, I bypassed this valve by removing the vacuum pipes from the solenoid and connected them together to put the max vacuum to the turbo. I started the engine and GENTLY revved the engine and could see the rubber pipes expanding which ment the turbo was ok, you can also check for leaks at this stage. Dont be tempted to over rev it or somthing will go bang!

A known good solenoid was sourced from my local scrappy and now it it pulls like a train thro to 4500 rpm. This has also been improved by removing the EGR and blanking it and drilling out the guts of the cat!!

If in doubt just buy a new OEM one and try it, it will still be cheaper than taking it somewhere.