Control limit exceeded cylinder 4 injector pump

**jimgironde** · 04-06-2008,01:46 PM

57 plate 140 tdi se passat estate.

I posted a problem on the passat section of this site a couple of weeks ago called "diesel backfire" here is the link https://www.vwaudiforum.co.uk/forum/s...ad.php?t=38005

I have just got car back from main dealer and they reported a fault code "control limit exceeded cylinder 4 injector pump" They were not able to say what it was and as it had only recorded once they said it was not a problem.

Was this the cause of my problem, what does it mean and is there anything to worry about?

They also updated the ECU to version 12 dated 31/10/07. Anybody know what the update included?

thanks guys

**jimgironde** · 21-06-2008,05:46 PM

I have bumped this up in the hope of a reply

thanks

**black_one** · 20-09-2008,05:58 PM

u have to change the injector pump of cylinder 4.

**Crasher** · 20-09-2008,06:55 PM

In my experience this is a faulty injector but getting VAG to change one under warranty is a joke even when they use their GFF software. If it was out of warranty, I would suggest considering going to an independent but remember it is not a five minute job on the 2.0L 16v TDI as it requires great care and specialist VAG tools. As it is in warranty, ask them to produce a Guided Fault Finding report on the injectors.

**kenney** · 20-09-2008,07:34 PM

Hi As you say Jim an intermittent fault is usually,hard to locate.The biggest problem is when using the fault finding system the values of the injectors freeze at 1500 rpm and most of the problems seem to occur from 1800 rpm to 2200 rpm, which means you have no valuable readings of the injectors, when the fault is present.This in turn makes it hard to diagnose the problem.However we have been informed before replacing any injectors,the injector wiring loom must be replaced as the second stage of solving the problem,and the first stage is updating the ECU.

**jimgironde** · 23-09-2008,08:21 AM

thanks for those replies guys.

I am not sure what I should be doing, are you saying that getting a code like this is "terminal" and that if you get it once then eventually the pump needs replacing. Or do I go along with the dealers opinion of don't worry unless it happens again?

I have certainly not had this misfire/backfire again but what I do get from time to time is a whiff of diesel in the cabin that lasts for a couple of minutes whilst I am driving. Is this another symptom of the same problem?

**Crasher** · 23-09-2008,03:56 PM

Has the car had the in tank lift pump “Campaign” replacement done? It will be in the back of your service book.

**jimgironde** · 23-09-2008,04:25 PM

Crasher, no it hasn't. Can you tell me what it is and what effect it has please.
I am on the Passatt B6 forum every day and nobody has posted anything about this?

Thanks for your comments todate I really appreciate it.

**jimgironde** · 23-09-2008,05:34 PM

sorry that is not the fuel pump replacement is it, apologies, if it is I didn't recognise the terminology!

Yes the fuel pump was replaced a couple of thousand miles ago. This was long after the injector pump code and I had smells of diesel both before and after the fuel pump was replaced.

**Crasher** · 23-09-2008,06:22 PM

The new pumps have been accused of causing diesel smells; I have heard a number of reports over it. I think the fuel returned from the tank is too hot. I am still trying to collate a percentage failure rate of 1.9 8v’s against 2.0 16v’s as I think the fuel return temp is higher but trying to compare this is difficult in running the two models side by side logging the temps as that is the only way it would be a fair comparison.