Can the OPS be replace without removing the pump?

[noelb]

I remember reading that someone once changed the OPS whilst the IP was still on the car...

I have an unwavering Code P0251. (IP Cam Reference Missed showing 8 - meaning it is a Hard Code - Not intermittant.) :(
I have seen no change at all in 1/2 of idling or driving.

All checks of electricals rule out Open Or short circuit or bad PCM. Points to Failed OPS in the IP. Nearly 250,000 km or 156,000 miles since new. I suspect the IP has never been changed.

Do I:-

1. Attempt to Change the OPS Without removing the pump?

2. order a pump and change it myself?

3. take it to the Diesel Fuel Injection workshop and have the pump rebuilt?


Any other options???

I suppose a Timing chain would be good. is the DSG Dual Idler gear set up still the way to go?


BTW do I need a 5521 pump? where do I find the number?

[LanduytG]

I remember reading that someone once changed the OPS whilst the IP was still on the car...

I have an unwavering Code P0251. (IP Cam Reference Missed showing 8 - meaning it is a Hard Code - Not intermittant.) :(
I have seen no change at all in 1/2 of idling or driving.

All checks of electricals rule out Open Or short circuit or bad PCM. Points to Failed OPS in the IP. Nearly 250,000 km or 156,000 miles since new. I suspect the IP has never been changed.

Do I:-

1. Attempt to Change the OPS Without removing the pump?

2. order a pump and change it myself?

3. take it to the Diesel Fuel Injection workshop and have the pump rebuilt?


Any other options???

I suppose a Timing chain would be good. is the DSG Dual Idler gear set up still the way to go?


BTW do I need a 5521 pump? where do I find the number?

OPS can easily be changed without removing the pump. Cam reference code is most likely the crank position sensor. Does it take several cranks to start?

Greg

[noelb]

It takes a while to get it started.

However the Number "8" reading I get is from the "Injection Pump" Cam Reference(ie Optical Sensor) meaning that the DTC is Hard not intermittant.

Can you buy just the optical sensor somewhere?

Bearing in mind the pump is probably 156,000 miles old... Is it time to change it and the timing chain? Maybe DSG timing Gears?

[LanduytG]

It takes a while to get it started.

However the Number "8" reading I get is from the "Injection Pump" Cam Reference(ie Optical Sensor) meaning that the DTC is Hard not intermittant.

Can you buy just the optical sensor somewhere?

Bearing in mind the pump is probably 156,000 miles old... Is it time to change it and the timing chain? Maybe DSG timing Gears?



Crank position sensor can cause the same problem. 8 means that it did not get a signal in 8 cranks so it goes to backup start mode. That is why it takes so long to start. The sensor is easy to replace and from what I remember not a lot of money. Also I think you can check the sensor with and ohm meter but I cannot remember what the value is suppose to be. Sensor is located on the drives side by the crank. The wire runs up to the top. I would check that before doing anything else.


Greg

[noelb]

Thanks greg. I'll try and put results on this post when the jobs done..

[arveetek]

I ordered a new optical sensor off ebay last week. $210 shipped. I could buy it from the local Stanadyne shop for over $300, but they didn't really want to sell it to me.

Here's the link to the guy who replaced it himself:

http://www.mamut.net/royh/newsdet9.htm

I haven't changed mine yet, but I'm planning to do it myself in the vehicle.

Casey

[noelb]

Thanks for that Arveetek. I had a new pump land in Australia Friday. The old pump has been dismantled and repair cost of $1900 AUD. Brand New pump cost $1760 AUD delivered.

We will see if it makes a difference.

I was thinking however that if you were to replace the pump and the timing gears/ chan at the same time you could perhaps get away with not touching manifolds etc... Maybe I am wrong... doesn't matter anyhow.

[noelb]

Brand New DS4 pump fitted and problem solved. Appears my diagnosis was correct.

It worked out cheaper to fit a new pump than to repair the old pump and I got a new PMD with the New pump.;)

There are some good prices on new pumps out there!

Oh and to answer the question Yes the Opticla sensor in the Pump can be replaced without removing the pump from the vehicle but it can upset the fueling... according to the mechanic.

Now I wonder... If you change the fueling does that mean more fuel and more power?

[arveetek]

Oh and to answer the question Yes the Opticla sensor in the Pump can be replaced without removing the pump from the vehicle but it can upset the fueling... according to the mechanic.

Now I wonder... If you change the fueling does that mean more fuel and more power?

Well, all I can say is that I changed the optical sensor myself, and wow! What a difference! It actually runs like a turbo diesel now! Much more power, and seems to be running smoothly with no ill side effects. Boost is stable now with a Turbo Master installed as well. I do have black smoke now when I punch it, which I never did before, so I know I'm adding more fuel. I just hope I'm not harming anything, but all gauges appear normal.

Casey

[noelb]

Sounds like you may have increased the fueling. Interesting...