TD5 won't rev up properly after head gasket replacement

Hi all. We have a 2000 W TD5 auto with 116k on the clock. There was air getting in to the cooling system, so we replaced the head gasket, getting the head skimmed and a correct sized gasket to fit.

Since then, the car suffers from a lack of power - it's like the turbo isn't working properly. The engine itself runs sweetly enough, and there is no smoke coming out of the exhaust. We have an 04 discovery here too, so we've had the chance to swap over some parts. So far, we've checked the following... *takes deep breath*

Plugged it in to our diagnostics box - no fault codes
Swapped the turbo
Swapped the Air Flow Meter
Swapped the crank sensor
Swapped the fuel pump
Got it checked on another workshops diagnostics machine - no fault codes
Rechecked the timing
Replaced the injector seals
Rechecked the injectors
Checked the intercooler hoses for splits
Checked the EGR
Replaced the fuel and air filters
Checked that the exhaust isn't blocked
Checked the fuel pump relay
Checked the ECU relay
Checked the Fuel Pressure regulator and associated pipes.
Replaced the injector loom.
Purged the fuel system.

All to no avail *cry*. Does anyone have any ideas? It's the lack of diagnostic codes which puzzles me most. Performance was fine before we set to work (!) All advice gratefully accepted.

uiop

hi m8,im 99%sure you cant skim the cylinder heads on the td5,but you say yours is running,albe it poorly?.....strange.....,anyway,check that youve set the lash adjusters correctly,you did put each injector back into its corrisponding cylinder?as these are coded into the ecu.

Fuel pressure is the only thing not monitored by the ecu so if its anything to do with the fuel system you wont get any fault codes.

If its only since the head has been off then it must be something you've done, are the fuel pipes on the right way? Sounds strange but in some cases it'll still run but won't rev. did you use the timing pins to time it up? It only has to be out a nats cock and you'll have problems.

Also as said above, make sure the injectors are in the right cylinders, if they're not then you can recode the ecu to the new injector grades to save swapping them. If all 5 are mixed up then it either won't start or won't rev.

uiop said:

Hi all. We have a 2000 W TD5 auto with 116k on the clock. There was air getting in to the cooling system, so we replaced the head gasket, getting the head skimmed and a correct sized gasket to fit.

Since then, the car suffers from a lack of power - it's like the turbo isn't working properly.
All to no avail *cry*. Does anyone have any ideas? It's the lack of diagnostic codes which puzzles me most. Performance was fine before we set to work (!) All advice gratefully accepted.

uiop

Click to expand...

Buy and fit a turbo boost gauge. I have one in my TD5 Disco. £20.
YES OR NO - when you deck it and hit 1,600 rpm or more, does it get 1 BAR boost?

Also make CERTAIN the EGR is disabled and BLOCKED. There's just a chance it may be jammed open and filling the inlet with exhaust. A blanking plate for a fiver will make sure this isn't happening.

But fit the boost gauge soonest as no boost means bugger-all power.
Remember, in the TD5 Disco (but not TD5 Defender) the turbo boost is controlled by the ECU. You MUST find out if the boost is missing, and then you can find out why.

CharlesY

Hi, mine did this last year. Head went, loss of coolant slight overheat (went into limp home mode), had head skimmed (can do this thread on here somwhere) and then had three weeks of back and forth to independant garage as I had lost all guts. lovely on tick over but just enough power to pull away.

Took it to a guy who loves challenges on 4x4`s and it turns out the injectors have a plastic/rubber bit that if it gets too hot it melts and blocks the hole(s), I`m no mechanic at all but what i got back was a totally different car better than it ever had been, recently done EGR and it cant get any better.

think i have the same problem on a td5 after replace the head gasket

they say that the injectors are damaged(hapens a lot)???

Hello all. Thanks for the pointers. It was indeed the injectors that were playing up. We got them overhauled at Feather Diesel Services near Halifax, and now the thing pulls like a train.

Can i ask what they cost you to get them over hauled and also which garage you use for you maitainence i am based in Brighouse so its handy to know these things

Hi Yorkshireman. We did the work ourselves (I run a small 4x4 Sales and Service centre), but we're actually in Greater Manchester (and I'm a little embarassed about the amount of work that we had to do to identify the fault tbh!).

Feather Diesels price was less than the cheapest quote I got for recon. injectors from both our local LR dealer and an independant. Not cheap, but my customers car is back on the road and I'm a happy man.

Cheers thanks