Still Having Trouble With P1250 Fault Code

[Wycheee1970]

Hi can anyone help I've been having trouble with my 2002 rav4 D4D with fault code P1250 it's been in the garage an they had a look at the waste gate which was a little stiff an eased checked a few other things including vsv which is blowing thru when checked from a diagram on here it shouldn't. Ran the car over the weekend an the fault of the engine cutting back to idling speed an management light coming on only happens now an again especially when the engine is cold which is baffling the mechanics has anyone got any advice on what to try next and does anyone know if the vsv should blow thru from port e to g. Many thanx

[igormus]

Hi can anyone help I've been having trouble with my 2002 rav4 D4D with fault code P1250 it's been in the garage an they had a look at the waste gate which was a little stiff an eased checked a few other things including vsv which is blowing thru when checked from a diagram on here it shouldn't. Ran the car over the weekend an the fault of the engine cutting back to idling speed an management light coming on only happens now an again especially when the engine is cold which is baffling the mechanics has anyone got any advice on what to try next and does anyone know if the vsv should blow thru from port e to g. Many thanx

sorry mate

i ve not a code reader but could you please have it decoded to start to think.

cheers.Igor

[Wycheee1970]

It says turbo malfunction. We have freed the waste gate we need to find out if the vsv is working properly but not sure how to tell. All this has happened since it stood for 3wks then had flat batteries.

[igormus]

It says turbo malfunction. We have freed the waste gate we need to find out if the vsv is working properly but not sure how to tell. All this has happened since it stood for 3wks then had flat batteries.

hello again

what is the task of VSV ?? what it has been designed for?

the malfunction is considered as low air pressure or exhaust gas temperature is not dropped after the turbo -- in other words the gas does not work as driver in full. if the gas energy is not enough then the turbo might to have an issue with actuator/drive to govern vanes and follow the engine load/condition.

Cheers/Igor

[Wycheee1970]

Any ideas how to rectify?

[igormus]

Any ideas how to rectify?

hello

as to vanes --they must easy respond to an actuator command. An actuator (vacuum side)is connected with the intake manifold. The more RPM of the engine the more suction/vacuum and finally this vacuum moves a membrane with rod link connected with vanes control ring. The vacuum is considered as constant (subject to engine is in order)-- as to an actuator performance -- it depends on the membrane condition -- if it has no vacuum bypassing (due to cracks/leaks), then an actuator itself must to work properly. Now regarding to vanes -- they have been designed as variable and change throttle hole width between two neighbor vanes by a command of an actuator via control ring that links all vanes. Now sometimes the vacuum creates in the suction line is not enough to move an actuator link due to vanes flexibility lack on their axises. What does it mean -- the carbon deposit is guilty. Finally the turbocharger can not reach its maximum RPM depending on the engine current condition/load and short charges cylinders. The air boosting pressure is normally measured by a special pressure sensor that gives a command to the ECU. IF something is wrong with boosting air pressure (out of limits)-- then ECU records this fault as in code -- this is one possible fault. Now regarding to another one -- as was reported above re throttle hole width between two neighbor vanes is changed. The initial exhaust gas parameters have both pressure and respecting temperature. AS to the thermodynamic -- both P and T are prorated and when passed thru the throttle hole -- both P and T are being reduced because of the nozzle reduction and in cacse both remain unchangeable or so -- it is a signal for ECU. The temperature after turbocharger is normally measured by a sensor that also gives a signal to ECU. Now you can see both coded signals with the same meaning as turbo failure. Now regarding to how to cure that -- the diesel with turbo are the one UNIT and always depend from each other. Time to time the turbo must be dismantled, cleaned , worn spares must be changed, the rotor must be balanced. A special service kits are normally sold. Your task is to locate reliable garage who deals with daily turbos repair/service.

Cheers/Igor

[Wycheee1970]

Thanx igor will pass onto the garage thanx for advice. Mark