Diesel starting.

[Davey1991]

I have read several topics on the issues with diesel starting.

The reason for this thread, my car will not consistently start well or poorly.

When cold it sometimes starts acceptably, then the next day it will take 2-3 seconds but it never fails to start.

When warm I have a similar issue again sometimes starts 2-3 seconds sometimes I have to crank for a good 5 plus seconds.

My head says injectors which is annoying with a car I have just purchased. Is there anything else I should be checking, leak back test is on the cards when I can get to my test kit, I have a new in tank pump sat in the boot as well, just in case.

Regards, James.

[Dragrad]

What is the fuel level in the tank ?

Best fit the in tank fuel pump to assist the under-bonnet one, which could be partially failing ? There is a How To on here...

Hope you get it resolved soon....

[RogerHeinz57]

Hi James.
There are many ways to diagnose this issue, most of which include an element of guesswork, some from experienced folk and from folk who have no idea at all. This includes those who don't read the original post correctly.
To eliminate guesswork, and nail the problem correctly without spending huge amounts of £, it would be worth having a T-4 session by a skilled technician who would tell you all about the problems and codes logged within the ecu's. This will be more thorough, and cost effective in the long run and enable some enjoyment of ownership. Sometimes a sensor can cause huge problems and only cost a few £, rather than replacing everything else first and diagnosing the last thing as the cause.

This is my opinion and hope that all the armchair diagnostic specialists here don't tempt you with their huge lack of knowledge experience or inability to read properly what is written in front of them to generate their useless responses.

Hope you can get this sorted.

Cheers JohnH.

[FrenchMike]

For peace of mind,carry out a injector leakback test firstly ...

Mike

[hogweed]

What John said.

But it's also worth checking your plenum for Swimming-Pool-Syndrome.

[Davey1991]

Originally Posted by John H

Hi James.
There are many ways to diagnose this issue, most of which include an element of guesswork, some from experienced folk and from folk who have no idea at all. This includes those who don't read the original post correctly.
To eliminate guesswork, and nail the problem correctly without spending huge amounts of £, it would be worth having a T-4 session by a skilled technician who would tell you all about the problems and codes logged within the ecu's. This will be more thorough, and cost effective in the long run and enable some enjoyment of ownership. Sometimes a sensor can cause huge problems and only cost a few £, rather than replacing everything else first and diagnosing the last thing as the cause.

This is my opinion and hope that all the armchair diagnostic specialists here don't tempt you with their huge lack of knowledge experience or inability to read properly what is written in front of them to generate their useless responses.

Hope you can get this sorted.

Cheers JohnH.

Thanks John, luckily I do have a few years in the motor trade under my belt running a garage and looking after commercial vehicles and as you aptly said, "everyone is a mechanic." I also agree with you completely on the sensor side but it just doesn't seem consistent enough, then again I have had weirder things happen due to sensors.

Originally Posted by FrenchMike

For peace of mind,carry out a injector leakback test firstly ...

Mike

I think this will be next on the cards, slightly less worried about injectors now having seen the price of reconditioned tested units. Do the 75 and zt parts interchange? Are there several part numbers?

Originally Posted by hogweed

What John said.

But it's also worth checking your plenum for Swimming-Pool-Syndrome.

Plenum is dry as a bone, luckily even before buying the car I knew of this after saving a 75 from imminent ecu doom

Originally Posted by Dragrad

What is the fuel level in the tank ?

Best fit the in tank fuel pump to assist the under-bonnet one, which could be partially failing ? There is a How To on here...

Hope you get it resolved soon....

Full or very very nearly, with my car being an 05 face-lift I believe it only has the one in tank pump, would this mean that it would not start if this had failed?

Thanks everyone for the quick response, this is quite possibly the nicest car specific forum I frequent, definitely the quickest most helpful responses!

[hogweed]

Originally Posted by Davey1991

Plenum is dry as a bone, luckily even before buying the car I knew of this after saving a 75 from imminent ecu doom

Wouldn’t want to labour the point, and it’s probably not the cause… but my plenum was as dry as a bone also, yet it turned out that it hadn’t been at some stage in the past – the ECM had a tide mark on it. I was very sceptical, but Marinabrian did me an exchange unit, and the problem went away.

So maybe worth whipping the ECM out and having a look… in any case, T4 would seem to be the only logical next step.

[HarryM1BYT]

I agree with FrenchMikes suggestion of checking for leak-back - not enough pressure being available at the injectors, due to it leaking back to the tank past one or more injectors. It can be checked at no cost if you read up on the issue and it only usually shows up as a problem on initially starting the engine.

[unimatrix1066]

First check The pumps

Then check for leak back , both easy enough to do I ve had a few m47 diesels I've had 1 in tank pump two under bonnet ones and 2 injectors plus a water logged plenum
What sort of miles has it done?

[Davey1991]

Originally Posted by unimatrix1066

First check The pumps

Then check for leak back , both easy enough to do I ve had a few m47 diesels I've had 1 in tank pump two under bonnet ones and 2 injectors plus a water logged plenum
What sort of miles has it done?

With it being a face-lift and an 05 surely it only has the in tank pump? Is this Correct? It's quite low mileage at less than 80k. Next step is a leak back test I have done several on this engine mainly 75's before and countless on other mainly just looking for something I may have missed. There are no apparent water marks on the pollen filter or around the plenum which I think is a good sign.

Thanks for the suggestions I shall report back.