Discovery TD5 Throttle Lag

Hi Guys,

Been scratching my head on this one for a while now. I've bypassed the clutch switch as this was giving the over-rev issue.

When I go to pull away, the engine seems to hesitate to build revs when pulling away, but once the vehicle is moving, the throttle response is what I would expect. Anyone else had this issue?

Also, I don't know anyone else with a TD5 so can't test against theirs, but 3rd gear has lots of power and climbs to 4000rpm with great ease. But when in 4th gear (still accelerating), it's like it's run out of breath..?

The first thing I would be doing is replacing the clutch switch rather than just bypassing it. The ECU isn't going to know what you're doing with the clutch and so it's unlikely that it's going to respond as the software intends it to.

brian47 said:

The first thing I would be doing is replacing the clutch switch rather than just bypassing it. The ECU isn't going to know what you're doing with the clutch and so it's unlikely that it's going to respond as the software intends it to.

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This was one of mt suspicions, hence why I mentioned it. But I was curious if anyone else had exoerience this too, seeing as bypassing this switch is so common.

And I know someone with a TD5 in Disco 1 that doesn't seem to have any issues and they don't have the switch either, but don't seem to suffer this issue (10P - same as mine)

try unpluggibg the maf sensor, if its better you need a new maf

johnlad said:

try unpluggibg the maf sensor, if its better you need a new maf

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MAF is fine

check the hi-low switch inpiut with nanocom cos if it's stuck in low even if the box is in hi the ECU works on a different fuel map which is not suitable for hi range

Simon098 said:

MAF is fine

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Have you actually tried disconnecting the MAF, or are you just assuming that because it's been replaced recently, that is must be ok?

sierrafery said:

check the hi-low switch inpiut with nanocom cos if it's stuck in low even if the box is in hi the ECU works on a different fuel map which is not suitable for hi range

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I thought the failure mode was always to be in HI?

Cheers

Also, if you want to see if the switch is working try selecting HDC, this will only work in LO, if you try in HI then the warning will sound and it will not allow HDC to be engaged.

Cheers

neilly said:

I thought the failure mode was always to be in HI?....
Also, if you want to see if the switch is working try selecting HDC...../.

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yes.... as long as it's not a short to earth on the circuit...good point with the HDC, IMO this is something to be ruled out just for peace of mind

sierrafery said:

yes.... as long as it's not a short to earth on the circuit...good point with the HDC, IMO this is something to be ruled out just for peace of mind

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MAF has been replaced and checked with Nanocom (60 at idle, 600 at full throttle)

Low, High switch works correctly and tested the HDC button, constant beeping when in high box, not in low. Also checked with Nanocom