2.1td low power

davethewheel · Post by **davethewheel** » 13 Mar 2008, 19:07

my 1997 2.1td xantia has suddenly lost power ,it will rev freely but it won't pull very well, i can still hear the turbo spinning up and that sounds normal, i've checked the pipe from the turbo and the intercooler and all looks ok, it only started this morning but it hasn't improved, also if i plant my foot down it's completely flat and doesn't even blow any smoke out which it normally would

Post by **RichardW** » 14 Mar 2008, 07:38

Check that you haven't popped off one of the air hoses between the turbo,intercooler and engine. Done this on a 1.9TD a couple of times (like pulling hard up the dual carriageway uphill sections on the A66

) - and they are as flat as afterwards....

Post by **CitroJim** » 14 Mar 2008, 08:52

I love how the hoses can come off with a very healthy POP

If not this, have a check of your MAP sensor. It's a square box down by the intercooler with an electrical connection on one side and a small pipe going into the intercooler.

Another cause might be a stuck EGR valve.

davethewheel · Post by **davethewheel** » 15 Mar 2008, 22:20

ok a bit of a update, i've checked all the hose's and there all ok , the EGR valve has been disconnected for the last year ,checked all the electrical connectors that i can see, the problem now seems to be intermittent, some times it's completely normal and i can switch it off and when i start it again it's lost it's power again

AndersDK · Post by **AndersDK** » 15 Mar 2008, 23:18

Dave you have a small rubber line from the inlet to the diesel pump somewhere. This rubber line transfers the inlet (i.e. turbo) pressure to tell the diesel pump to add more fuel when the turbo comes to work.

This rubber line may be perished or blocked by oil.

davethewheel · Post by **davethewheel** » 16 Mar 2008, 00:41

AndersDK wrote:Dave you have a small rubber line from the inlet to the diesel pump somewhere. This rubber line transfers the inlet (i.e. turbo) pressure to tell the diesel pump to add more fuel when the turbo comes to work.

This rubber line may be perished or blocked by oil.

thanks anders, i will check this in the morning.

Post by **CitroJim** » 16 Mar 2008, 08:37

AndersDK wrote:Dave you have a small rubber line from the inlet to the diesel pump somewhere.

Nothing so simple on a 2.1 Anders

It's all electronic and "fly by wire" so the nice simple pipe from inlet to pump does not exist. The role formerly adoped by this pipe is now performed by the MAP sensor I referred to in an earlier post. The pipe to that could be persished though.

Dave, another thing worth checking is that the turbo pipe that runs right under the engine has not been grounded at some time and has a pinhole or two in it.

Check too the throttle cable is OK. It drives a big potentiometer (pot) which can be found under the airbox.

Don't discount air in the fuel lines. Do all the usualy checks you'd do for a 1.9TD. If yours is anything like mine, all the fuel pipes from the priming bulb onward are all transparant.

davethewheel · Post by **davethewheel** » 16 Mar 2008, 11:59

your right jim, mine has a lucas epic pump, all the turbo pipes are ok i've already replaced the pipe that runs under the engine i've had that go before.
throttle cable is ok does it not sound as if it's some kind of electrical/sensor problem as it's intermittent and some times the car feels completely fine, the engine management light has not come on at anytime though.
is there any other way to check for air in the fuel lines, i've watched the clear section of hose when it's running and when i rev it and it all seems clear.

Post by **CitroJim** » 16 Mar 2008, 12:32

Hi Dave,

If you see no air in the lines then all will be OK in that department and all the mechanical bits have been eliminated. I really would be inclinded to suspect a sensor and my first choice would be the MAP sensor. There are no tests that can be peformed on it, substitution is the only answer.

The other sensors are the coolant temperature sensor (CTS) (blue one near the fuel filter) and the inlet air temperature (IAT) sensor on the top turbo hose going into the inlet mainfold runners.

Both these can be checked with an ohmmeter. The CTS should show a resistance of roughly 2.3K to 2.6K at 20C and the IAT roughly the same. there is a fuel temperature sensor inside the pump along with timing sensors and so on but these are difficult to test.

Like the 1.9TD it has a TDC sensor and Needle Lift Sensor on one of the injectors but if there was a problem with these I'd expect the Engine Management light to flash on and/or the tacho to play up. Either one of these failing would make the engine run really roughly.

My money remains on the MAP sensor. One point is that it has two possible locations, either down by the intercooler or up on the inlet mainfold airbox just to the left of where it says "12V DIESEL" On mine, the MAP sensor is by the intercooler and the alternative location on the manifold is sealed with a blanking plug which works loose over a period of time.

It might be worth cleaning the connections to the CTS and IAT.

Have you tried a dose of diesel fuel treatment? Tesco do some quite good stuff.

If the problem remains elusive, a diagnostic session by a diesel specialist may be needed to try and pinpoint the problem. They should be able to read the ECU and see what it is up to but the intermittent nature of the problem makes this difficult.

MikeT · Post by **MikeT** » 16 Mar 2008, 15:43

davethewheel wrote: the engine management light has not come on at anytime though.

I was wondering if the intermittent reason is the ECU going into LOS (limp home) mode which should bring up the engine management light. Is the light proven to be working? (Sorry if I'm on the wrong track, I've had my nose stuck in ECU tech-books the last week).

davethewheel · Post by **davethewheel** » 16 Mar 2008, 15:45

hi jim
i'm sure i changed the coolant sensor on the cylinder head when i got the car it has erratic tickover and changing it seems to cure it.

i've got a friend at work who is a sparky so i'll get him to check the resistance on the sensors.

i've actually got a brand new injector with the Lift Sensor on it i bought it a while ago from ebay for a fiver but like you say the engine would normally run rough and it doesn't, no engine management light either.

come to think of it a friend of mine has a vw passat that had a faulty map sensor on it and if felt the same to drive engine was nice and smooth and revved ok but was very flat to drive, i'll check the connections on mine and i may as well bung some cleaner through as well.

thanks for your help

dave

DickieG · Post by **DickieG** » 16 Mar 2008, 16:03

If there is a delay of a second or two after the engine starts before the 'K' light goes out then it has a fault logged in its memory, if it goes out right away then no fault is logged.

If you think a fault is logged and you're anywhere near M26 J15/16 give me a shout and I'll plug in my code reader for you.

davethewheel · Post by **davethewheel** » 16 Mar 2008, 17:27

haven't seen a delay in the light going out but i've noticed that the light flickers when you turn the ignition on the goes out when started.

davethewheel · Post by **davethewheel** » 21 Mar 2008, 21:42

well I've checked everything i could think of and cannot find any problems ,the problem seems to have gone away now it's not done it now for about 3 days maybe it's fixed it's self

I'm not counting my chickens it's bound to come back

AndersDK · Post by **AndersDK** » 21 Mar 2008, 22:29

I've got to write in my palm : a 2.1TD have a MAP sensor - oddly to a diesel - but anyway its the latest development of the IDI diesel with the epic pump

But a map sensor is rather consistent : either it works or not. Since the problem is away for now, I'm pretty sure its the old wellknown problem with air in the fuel lines.
Its such a nuisance as this problem type does in fact have the nature of coming and going, depending of how much air comes into the lines.