1.9TD Xantia engine running issues

[firstrebel]

I have two small issues with the engine in my Xantia 1.9TD SX (built 3/1996, reg 1/1997). It has the Bosch mechanical fuel pump.

When warm it ticks over at about 850/900rpm but is 'lumpy'. You can feel the shimmer when sitting in the seat. To get a smooth tickover it needs to be at 1000rpm.

I get kangarooing when decelerating through certain speeds, eg, 3rd gear at 40mph.

Anything wrong here or is my brain still in petrol engine mode?

Bob

[MikeT]

That doesn't sound right, so no, it's not you.

My first guess is injection timing is slightly out.

[firstrebel]

Is this easily checked and rectified?

Bob

[DickieG]

To check the timing its a case of removing the timing belt covers and inserting rods into the flywheel, camshaft and pump sprockets to ensure they all line up.

[red_dwarfers]

Would it be worth replacing the fuel filter and checking the pickup in the tank or am i barking up the wrong tree?

[firstrebel]

To check the timing its a case of removing the timing belt covers and inserting rods into the flywheel, camshaft and pump sprockets to ensure they all line up.

Not a 5-minute job then..

Bob

[firstrebel]

Would it be worth replacing the fuel filter and checking the pickup in the tank or am i barking up the wrong tree?

It has a new fuel filter. The old one was quite clean.

Bob

[red_dwarfers]

It has a new fuel filter. The old one was quite clean.

Bob

How about the pickup filter in the tank? These can get rather clogged up, located under the OS rear seat carpet, worth checking even if its not the root source as its a lot easier than checking the timing.
Theres a few threads about it in the depths of the forum somewhere.

[DickieG]

How about the pickup filter in the tank? These can get rather clogged up, located under the OS rear seat carpet, worth checking even if its not the root source as its a lot easier than checking the timing.

In my experience blocked filters usually show up up when under firm acceleration at high rev's due to the increase in fuel demand.

[DickieG]

To check the timing its a case of removing the timing belt covers and inserting rods into the flywheel, camshaft and pump sprockets to ensure they all line up.

Not a 5-minute job then..

A good time to check it would be when you change the top engine mount.

[CitroJim]

Bob, Richard,

I cannot recall now if your pump is the VP20 fully mechanical or the semi-electronic AS3. I have a feeling it's the former...

In that case, after checking the mechanical timing of the pump, cam and crank, it'll be worth checking that the cold advance is being correctly released when the engine is at normal running temperature. This can be checked by measuring the voltage on the cold advance electrovalve on the front face of the pump (as you look at it) When cold, you'll see 12V on the electrovalve and 0V when the engine is hot. If the cold advance is on all the time it'll upset the overall advance curve.

Also, it's worth checking the static timing of the pump itself and this can be done reasonably with a trained ear. It's worth checking as natural wear in the pump can change it's static timing.

In the past, I've set timing so that just the merest trace of diesel knock can be heard at idle but not so much that has a metallic tinkling sound. Revving from that point should result in a rapid, clean acceleration with not a hint of diesel knock whatsoever.

If after all that and it's no better, the injectors may benefit from an overhaul.

Thinking on, this all may go some way to expaining why you feel the performance is generally a bit leisurely Bob...

[firstrebel]

A good time to check it would be when you change the top engine mount.

When I get the correct one

I cannot recall now if your pump is the VP20 fully mechanical or the semi-electronic AS3. I have a feeling it's the former...

In that case, after checking the mechanical timing of the pump, cam and crank, it'll be worth checking that the cold advance is being correctly released when the engine is at normal running temperature. This can be checked by measuring the voltage on the cold advance electrovalve on the front face of the pump (as you look at it) When cold, you'll see 12V on the electrovalve and 0V when the engine is hot. If the cold advance is on all the time it'll upset the overall advance curve.

Also, it's worth checking the static timing of the pump itself and this can be done reasonably with a trained ear. It's worth checking as natural wear in the pump can change it's static timing.

In the past, I've set timing so that just the merest trace of diesel knock can be heard at idle but not so much that has a metallic tinkling sound. Revving from that point should result in a rapid, clean acceleration with not a hint of diesel knock whatsoever.

If after all that and it's no better, the injectors may benefit from an overhaul.

Thinking on, this all may go some way to expaining why you feel the performance is generally a bit leisurely Bob...

And there I was thinking I was getting to the end of the list of jobs getting this car back to its former glory.

Bob

[AbangCorp]

do you have a engine / throttle damper anymore?

most of us don't, it will explain kangarooing behavior on your car

[firstrebel]

do you have a engine / throttle damper anymore?

most of us don't, it will explain kangarooing behavior on your car

Don't know what you are talking about. I am new to these French contraptions, my other cars are Volvo.

Bob

[DickieG]

do you have a engine / throttle damper anymore?

most of us don't, it will explain kangarooing behavior on your car

That's a point worth considering Bob, the damper is located on the front of the pump and looks like a shock absorber positioned at a 45° angle. Remove one of its securing nut's, if its OK then it will damp movement as you pull/push it.

these French contraptions

my other cars are Volvo.