TD5 Question

[zelko]

Hey Guys

Have been trying to fix a problem with a mates TD5 and wondering if anyone could shed some light for us. The problem is that when he accelerates sometimes he gets what feels like the engine cuts out for a millisecond or two and then it is fine, he has changed fuel filter, fuel pump and fuel regulator, check for oil in the ECU loom all ok, it is still doing it but not as often, car runs great when it is not doing it. It is like if you have a TDI and pull the wire off and on quickly on the stop solenoid. We are going to look at all the vaccum hoses next to see if any are damaged. Process of elimination. Oh and it only does it under load like going up hill, doesn't do it when you are sittng and revving it.

Any suggestions on what it could be would be greatful. Also what price are these nannocoms worth, and is there anyone in Brisvegas that we could come over and test the car on.

Cheers
Zelko

[Graz]

Could be oil in the injection harness. Do a search on this site as there are specific threads on the issue.

[Rosscoe68]

sounds like my old starlet turbo that had an overboost cutoff, to much boost would shut the engine down for 1/4 secod and boost would drop instantly as engine shut down, then all back to normal until to much bost again.

dunno if the td5 has overboost protection, just a guess.

[Graeme]

sounds like my old starlet turbo that had an overboost cutoff, to much boost would shut the engine down for 1/4 secod and boost would drop instantly as engine shut down, then all back to normal until to much bost again.

dunno if the td5 has overboost protection, just a guess.
This certainly occurs on TD5s when the boost modulator dies in the 'allow more boost' position. A typical indication is using wide throttle around 2500rpm the problem occurs but will rev right past on light throttle.

[Yorkshire_Jon]

The TD5 ecu does have overboost protection.

Does it cut out relative to boost levels or revs? If its rev related, you can probably discount overboost. From tickover in 3rd, when you boot it you should reach max boost within a short while, Im guessing that would make it judder????


Has the wastegate arm ever been adjusted to give more boost? Or is it normally driven very gently?

When the inlet manifold sensor detects an increase in pressure (more than the prescribed limit) it will automatically cut off the fuel until the boost pressure reduces to within acceptable levels. Giving the on-off-on-off scenario.

Over here in the UK a common cause of that is a sticking wastegate. A penetrating/releasing agent sprayed into the butterfly housing and generous working backwards and fourth may solve the problem... Other rectifications are a replacement turbo or get jiggy with the angle grinder, release and braise back up - they are supposed to be a non servicable butterfly. I have fixed 2 now with penetrating oil and a generous working.

[Blknight.aus]

try this...

test it a couple of times and see if it happens at a certain throttle position.

change into low range and see if it still happens in the same throttle position.

if it happens at the same pedal position every time then its the throttle position sensor.

If it happens at the same RPM's/load/boost and the pedal position changes then it could be a faulty MAF, dodgy connection thats breaking at a certain vibration oil in the harness or any number of other things..

[zelko]

Thanks guys will pass ypur thoughts on and see what we can find, fingers crossed, will keep you updated

[MickG]

I had exactly the same thing with mine and it turned out to be a sticking wastegate. Only did it under load or when accelerating hard. Quick lube and all back to normal.

Hope you sort it

[zelko]

Thanks mate, just spoke to my mate, he says that when he is sitting in the car out of gear, as he revs the engine and gets to 1200 rpm then it just goes back to idle then he sqeezes the throttle and gets to 1500 rpm and does the same goes back to idle and he says the engine light has come on, so it looks like a trip to the mechanics, so we should be able to find out what it is doing now.

[Blknight.aus]

try a trip to someone with a nanocom, T4 or one of the other rover diagnostic boxes....

which reminds me I need to butcher up a cable for mine...

[zelko]

Thanks, our mechanic has one so hopefully will get to the bottom of it. So where can we get one of these Nanocoms and how much are they.

Cheers
Zelk

[zelko]

Hey guys thought I'd give you an update on this problem, mate went down to our mechanic and he put on the diagnostic machine, found out it was in the Driver Command, was on setting 2, changed it to setting 3 and hasn't done it since fingers crossed, will keep a close eye on it as he said it actually might be in the wiring loom from the ECU to the dashboard.

Thanks to all for your inputs. Mate is a happy chappy again.

Cheers
Zelk

[Psimpson7]

Hey Zelko,

I am guessing you mean the Driver Demand Sensor (throttle)?

The setting in the ecu for teh 2 or 3 track throttle needs to match the throttle that is fitted. It either works or it doesnt so I would be suprised if thats what they did?

Rgds
Pete.

[zelko]

Thanks Pete

I'll check with my mate tomorrow and see if thats what he meant

Zelk

[Yorkshire_Jon]

TD5's prior to 2002 used a 2 pot throttle peddle, after 2002 they have a 3 pt model. ECU need to know which it is, otherwise no go.

The electrical bit of the peddle (i.e. the throttle pot) is not available as a spare part, you have to buy the whole peddle assembly... And they aint cheap! Fortunately mine was replaced under warranty - that was an awfully expensive plastic peddle cover for LR!!

Id be surprised if that was your problem. Sounds much more like a sensor at fault or maybe sticking wastegate.

[Psimpson7]

I bought a new spare 2 track throttle from LR for mine and paid about 70pounds. I though that was pretty cheap!

Pete.