Diagnosing fuel problems?

I have just corrected an issue I had on my defender TD5 with poor running.
I did believe it was a fuel issue from the start but what was causing it was a long journey in time and money.
I had no diagnostic tools so was using only what other people said I should try.
I turned out to be the fuel pump but after replacing the fuel filter, the injector seals and washers, injectors ultra-sonic cleaned, new injector harness, new internal valves in the filter housing there was only the regulator left and no one suggested replacing that.
Now what to get to diagnose a fuel problem in the future and how to go about the diagnostic processes will be most helpful.
As I see it a fuel pressure gauge would only give half the story a restriction in the system would still show full pressure but not deliver the correct volume of fuel.

Im guessing a gauge would still be useful as if there was a restriction the pressure may build up but slowly.
I like the td5 but it does seem to have more than its fair share of troubles and thats coming from a tdv6 owner
In tank uel pump problems arent unheard of on td5 models in fact its a fault shared with many makes and models.

lynall said:

Im guessing a gauge would still be useful as if there was a restriction the pressure may build up but slowly.
I like the td5 but it does seem to have more than its fair share of troubles and thats coming from a tdv6 owner
In tank uel pump problems arent unheard of on td5 models in fact its a fault shared with many makes and models.

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Yes you are correct fuel problems are common on a TD5 and a number of things can make the same symptoms making it more difficult to make a diagnosis without equipment and knowing how to interpret the findings.
What I would like to do is put together a fault finding flow chart so that I and anyone can diagnose a fuel issue with just basic equipment and not do what I have just done and found the problem by replacement until the issue has gone, that way is expensive and time consuming.