2001 V70 T5 Long Term Fuel Trim Upper Limit.

[Integrexman]

I have been doing some maintenance on my V70. I needed to replace my vacuum booster (vacuum leak) so I decided to replace several other hoses etc while the turbo was easier to get to. I think I may need a new MAF to get the long term fuel trim code to clear but I thought I would first make sure there are no vacuum leaks. I have a few questions.

Engine is B5234T3 R5 2.3L

1. What should the fuel pressure be? I get 47psi with key on and 52psi at idle. Pressure drops to 42 after one hour with engine off.

2. Were is the fuel pressure regulator? Most parts places say this is the sensor but I took the fuel rail off to clean the injectors but can not find it.

3. The check valve the brake booster hose connects to at the intake tree has a hose that goes to the intake air hose before the throttle body. It does not seem to move any air either way. What does it do? It looks like this one.

[KSUMMEY]

Your fuel pressure is pretty close

The regulator is in one of 2 places by the fuel filter under the car or most likely place is on the fuel pump assembly in the top of the housing. 380 kpa or 300 kpa depending on your fuel management system so 43 or 55 psi.

That is a picture of a fuel rail pressure sensor and they are prone to failure but it will set a code for it or you can monitor it with a scan tool for failure.

Its just tees in the vacuum line to the brake booster.

[abscate]

I have been doing some maintenance on my V70. I needed to replace my vacuum booster (vacuum leak) so I decided to replace several other hoses etc while the turbo was easier to get to. I think I may need a new MAF to get the long term fuel trim code to clear but I thought I would first make sure there are no vacuum leaks. I have a few questions.

Engine is B5234T3 R5 2.3L

1. What should the fuel pressure be? I get 47psi with key on and 52psi at idle. Pressure drops to 42 after one hour with engine off.

2. Were is the fuel pressure regulator? Most parts places say this is the sensor but I took the fuel rail off to clean the injectors but can not find it.

3. The check valve the brake booster hose connects to at the intake tree has a hose that goes to the intake air hose before the throttle body. It does not seem to move any air either way. What does it do? It looks like this one.

2. Were is the fuel pressure regulator (FPR) ?

If your car is ME7, and I think it is, you don't have an FPR, so no vacuum line.

Mike will check me on this but I believe no electronic throttle body (ETB) car has an FPR.

There is a small fuel damper under the fuel rail, but that is not an FPR.

Your fuel pressure is fine - spec is 20 psi after 20 minutes I believe.

[precopster]

Abscate is spot on. The fuel pressures you report are fine and there is no fuel pressure sensor on this year model. The one on IPD's site is for much later years.

Once you've eliminated vacuum leaks as suspect move on to other items.

A common issue with these cars is a torn intercooler hose at the clamp on the throttle body due to oil affecting the plastic. Remove it and check.

[Integrexman]

Here is a update.

I still have the LTFT upper Limit.

I have now had the intake off and replaced the PCV system. I installed a new intake and ETM gaskets. I have tested the Intercooler, CBV and wastegate and to make sure they hold pressure or vacuum. I did find that one of the 2 check valves for the EVAP vacuum lines was letting air by and after replacing the engine idles slower in Park/neutral. The one that was bad went to the inlet air tube going from the MAF to the Turbo. At Ideal it was letting air get pulled into the intake and the ideal would go a little over 1000rpm.

Over all the car runs better but still have the LTFT upper limit. The car starts fine but stumbles until the engine gets warm and the STFT kicks in. Then it runs fine under light and medium loads but when you put your foot into it and it has no pull.

I am thinking new MAF would be the next part to put in the canon. Any other ideas?