Td5 cylinder balance

Hi everyone, I have a problem with my 2006 Defender Td5.

About a year ago I had an injector failure (on the 5, at the electrical part) which I replaced with one sold used but working (now on the 3) the cause probably due to dirt because I found the diesel filter full.

With the occasion I changed washers and orings to all injectors.

I should mention that in reassembling the injectors I was very careful to adjust the injector clearance by going back one full turn as mentioned in workshop manual.

Before the failure the engine always ran well with a nice sound.

After replacing the faulty injector the engine immediately ran, always started immediately, no drop in performance. I have already run about 5k km but the sound make me think it is not at the top. don't know how to explain it but the sound is not healthy.

This afternoon I checked the cylinder balance using a diagnostic tool. These are the results.

I start the engine, let it slowly warm up. Once I reach the opening temperature of the thermostat I stop I read these values:

- Idle

Cylinder 1: -3 -2 -3 -1 +2 +3 +1 +3
Cylinder 2: -11 -10 -12 -13 -7 -8 -6 -10
Cylinder 3: +13 +10 +12 +16 +12 +15 +12 +17 +16 +17 +15 +16
Cylinder 4: -4 -3 -6 -5 -11 -10 -11 -8 -5 -9 -10 -9 -11 -5
Cylinder 5: +4 +3 -1 0 -1 0 +3 +4 +2

- Pressing the accelerator at 1500 - 2500 and 3000 rpm

Cylinder 1: -3 -1 -3 0
Cylinder 2: 0 -1 +2
Cylinder 3: +2 0 +2 -2 -1
Cylinder 4: 0 +2 0 +2 +1 0
Cylinder 5: -3 +2 +3 -1 +3 0


- After doing a piece of highway I check the cylinder balance again in idle and read these values:

Cylinder 1: -13 -12 -18 -13 -17 -16 -12 -9 -8
Cylinder 2: -4 -9 -14 -11 -14 -9 -13
Cylinder 3: +4 -1 +1 +5 +2 +5
Cylinder 4: +12 +8 +13 +12 +6 +9
Cylinder 5: +12 +14 +11 +13 +14 +12 +16 +17 +13


This is the situation.

What do you guys think?

If you notice at the beginning all cylinders have "acceptable" values except 3 (the one bought used) and then the situation is reversed?

Could this be the fault of the injector bought used but working? If it was not working properly I should have performance drops or smoke. Actually if it weren't for the sound not being round and those balancing values of the injectors the car would be perfect. It runs, it starts, it doesn't smoke....

I have already done 5k km. I have had no oil level increase.

If it were the injector wiring, it wouldn't give me such a constant problem without starting problems or performance drops.

In short, it seems that at idle the engine turns badly but without having differences in performance

What would you guys do?

Are'nt the injectors coded to each cylinder, the new used one will not be coded for your engine/cylinder, it may need recoding. ECU is probably running it at a generic default setting rather than optimum running

Some of them seem a bit high, but if the engine is running smoothly, then it's well within the capabilities of the ECU to sort it out. A friend's TD5 consistently gave cylinder balance readings in double figures on the middle cylinder, and ran happily for many tens of thousands of miles like that until eventually he crashed it and then it was stolen while in the custody of the insurance company, so we never knew what happened to the engine.

The larger values don't necessarily mean that he injector associated with them is duff. The ECU program is able to add additional fuel to some of the others, to compensate. For example, if an injector is delivering less than it says it is, then the program puts a bit more in some of the others to maintain parity between what's being delivered at the injectors and the signal from the crank position sensor.

Scooby22 said:

Are'nt the injectors coded to each cylinder, the new used one will not be coded for your engine/cylinder, it may need recoding. ECU is probably running it at a generic default setting rather than optimum running

Click to expand...

I proceeded to rewrite the injector codes. if I look with the nanocom the injector codes are exactly the ones I mounted in the position where they are

Brown said:

Some of them seem a bit high, but if the engine is running smoothly, then it's well within the capabilities of the ECU to sort it out. A friend's TD5 consistently gave cylinder balance readings in double figures on the middle cylinder, and ran happily for many tens of thousands of miles like that until eventually he crashed it and then it was stolen while in the custody of the insurance company, so we never knew what happened to the engine.

The larger values don't necessarily mean that he injector associated with them is duff. The ECU program is able to add additional fuel to some of the others, to compensate. For example, if an injector is delivering less than it says it is, then the program puts a bit more in some of the others to maintain parity between what's being delivered at the injectors and the signal from the crank position sensor.

Click to expand...

Honestly, I can admit that with dirty diesel an injector could have failed but that all of them are broken is objectively unlikely.
Counting the fact that the engine restarted immediately after replacing the faulty injector, that it has never had problems starting, has never smoked, has never lost power and that in this year and 5k km the situation has not minimally modified...

Looks like injector 3 isn’t happy, find a decent used one and put it in I dought they are much money, can’t buy them new anymore and when you could it was like 300 quid for 1

Discodevon said:

Looks like injector 3 isn’t happy, find a decent used one and put it in I dought they are much money, can’t buy them new anymore and when you could it was like 300 quid for 1

Click to expand...

I learned that you can no longer get new ones. On the other hand, buying a used one again I don't trust. I will buy a refurbished one paying more than what a new one cost...

Yes, there's lots of people recondition TD5 injectors these days. When mine stop working I'll probably go for a Diesel Bob/Ribble Valley Diesels job, as several people have had good experiences with them.

Hi everyone, I wanted to do a test.
Today together with a friend I removed the third injector (the one bought used) and swapped it with the one in position 1 (the one on the radiator side)

Currently I have this configuration
Position 1: Injector bought used (
Position 2: Injector originally 2
Position 3: Injector originally 1
Position 4: Injector originally 4
Position 5: Injector originally 3

These are the nanocom readings in idle

Injector 1: -6 -7 -6 -7 -4- 3- 2- 1 -7 -2 -7 -5 -4 -3 -5 -4 0 -1 1 -1
Injector 2: 1 -1 -1 -5 -3 -9 -7 -7 -8 -1 -4 -3 -4 -6
Injector 3: -1 5 -2 4 -4 1 7 -2-3 1 2 0 -2 1 3 1 2
Injector 4: -2 2 -7 0 2 -2 -3
Injector 5: 1 5 7 6 9 3 12 8 5 11 6 7 6 9 11 8

What do you guys think?

However, I noticed a big improvement, the engine at idle vibrates half as much as before. Efficiency and smoke unchanged (no smoke). Engine definitely vibrates less at idle and when driving at low speed under-torque (not my usual)

How do you think it is possible that by reversing two initectors the engine vibrates much less?
Acoustically there remains a tac tac tac that was not there before the fault....