M

Marco Polo

Member
Hi all. I have been reading countless threads on sluggish TD5's and it made me bold enough to buy a new Siemens/VDO MAF from Island 4x4.
Fitting this has made no difference.
I have a OBD scanner but they are useless on these cars. I can however view throttle position in live data. I thought I might have a duff throttle potentiometer as there is a massive dead spot between 1/4 and 3/4 pedal travel. It pulls off idle to about 1500rpm, then as your foot goes down further NOTHING happens. When my foot is almost in the carpet, stuff happens. This is worse when cold. As I am pressing the throttle (I know, it doesn't have a throttle..) The tps readout increases in a smooth and linear fashion, so now I am stumped.
I don't have a check engine light on but thats not to say there are no faults logged. I don't own or know anyone that owns a Nanocom or Hawkeye so I'm a bit hamstrung in the diagnostic department.

Other info: starts and idles perfectly every time.
New air filter
Boost modulator bypassed and wastegate set to start opening at 15psi
EGR deleted
MAP sensor and inlet manifold clean

Any ideas?
 
Buy a Nanocomm or Hawkeye and watch for codes.

I reckon there are uncleared or unread fault codes still
 
Probably sound advice. I don't quite have the money to shell out on a Nanocom right now but it would be a great investment I'm sure.

What does it take to illuminate the check engine light? Even unplugging the MAF didn't do it!
 
your vacuum pipes and turbo pipes all ok? check for splits

wastegate closing?
 
trax said:
your vacuum pipes and turbo pipes all ok? check for splits

wastegate closing?
Click to expand...

Seem OK.

Was having another play earlier. I had her at a steady 1600ish rpm while looking at Maf signal and I noticed the engine rocking on its mounts a bit. Is it possible to have an occasional miss without illuminating the check engine light?

BTW. It's auto. I know they're a bit slower off the mark but you shouldn't be able to count to 5 before anything happens...
 
Td5? Have you checked for oil contamination in the injector wiring loom? Usually shows itself as dirty oil in the red plug connected to the engine ECU. It's known or suspected to cause all sorts of engine problems.
 
Marco Polo said:
Seem OK.

Was having another play earlier. I had her at a steady 1600ish rpm while looking at Maf signal and I noticed the engine rocking on its mounts a bit. Is it possible to have an occasional miss without illuminating the check engine light?

BTW. It's auto. I know they're a bit slower off the mark but you shouldn't be able to count to 5 before anything happens...
Click to expand...

you sure it is the engine,and not the gearbox.when i bought my P38 Auto,it was pathetically slow,until i changed the oil and filter in the g/box,i used LUCAS oil auto oil,what a difference after that.
 
Sounds a little like a problem I had. Change the fuel filter and look for oil in the ECU red plug.
Fuel filter is a reealy good bet and only cost a few quid.
 
Definitely engine, though the gearbox programming, torque converter, and age don't help.
I have a service kit and 12 litres of full synthetic dex 3 to go in at some point.

I did find a little oil in the red plug and none inside the ECU. The p.o. claims the loom was done but I am assuming that's just lies as usual (no evidence other than say so)

They're not that expensive so I will probably go ahead and replace the injector harness.

I fitted a boost gauge too to check up on the boost situation. I was only getting 13psi. I've fiddled with the wastegate and now I'm topping out just over 18. Definitely a bit quicker but still dead at lower rpm.
 
Last edited:
call mike at dynachip . he will run a full diagnostic check and then remap it , the best money you will ever spend on it , done mine 2 years ago and it still pulls like a train , d2 td5 es auto
 
mewl20004 said:
call mike at dynachip . he will run a full diagnostic check and then remap it , the best money you will ever spend on it , done mine 2 years ago and it still pulls like a train , d2 td5 es auto
Click to expand...

+1,Mike is fantastic at remapping.:clap2:
 
Check all pipes re turbo, my disco 1 was like a slug for 2 years, thought that was normal, till I found a small split on the underside of a pipe, £3 for a new pipe, goes like a new vehicle !
 
Dafman1990 said:
I'm not sure mike would travel to New Zealand to run a diagnostic to be honest
Click to expand...

Indeed.

Also early non-flashable ECU.

There is a Superchip agent in NZ, or else postal re- chip to Alive tuning. Would cost a lot and I'd be without the car for a couple of weeks....

No idea how much Superchips cost here.
 
Marco Polo said:
Indeed.

Also early non-flashable ECU.

There is a Superchip agent in NZ, or else postal re- chip to Alive tuning. Would cost a lot and I'd be without the car for a couple of weeks....

No idea how much Superchips cost here.
Click to expand...

you need to get the car working properly before thinking of any re mapping, but mike can solder a new chip in if posted to him or swap your ecu for a flashable one
 
johnlad said:
you need to get the car working properly before thinking of any re mapping
Click to expand...

I quite agree. I would save for a Nanocom before saving for a re map anyway.

Does anyone know what the output should be (in volts) from the ambient pressure sensor in the airbox on a 15 deg day at sea level? This is the one sensor I'd like to avoid having to replace since it costs more than all the others put together!
 
Making progress.

I have now replaced all the filters and oil.

I have also replaced the boost modulator which has made a difference.

I also replaced the injector harness. There was a tiny amount of oil in the red plug so I cleaned it several times over a 24 hour period while some more oil drained through.

The previous owner mentioned having done the harness but either he was lying or the part he used is of very poor quality. There was distortion and blistering along the plastic rail, the o-ring through the head was very loose, and the wire gauge used is tiny compared to the replacement I have just fitted.

The 2000rpm shudder is now gone!
 
all better then. if you pull the maf plug it'll run in a default mapping. i know you bought a new one, but might be worth checking to see if it runs better
 
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