Scirocco TDi - crank no start but intermittent over 2 years!

[puzzle]

Hi

I have a Scirocco 2.0TDi Bluemotion, CFHC engine code, 140BHP.

I've had the car for 2.5 years and during that time I've had nothing but trouble with it, but I have a recoccuring issue with the vehicle intermittently not starting. This issue has been on and off for over 2 years now!

When I initially got the car, it absolutely refused to start when warm. Looking on here led me to believe it may be battery, so I took a punt and got a Bosch AGM battery and that cured that issue.

About a month after buying the car, I'd been at work all day and then the car wouldn't start, it would crank but not start. Anyways, I left it for a few minutes and then it started. For the next 4 months, it started without an issue, so I thought nothing of it.

However, about 4 months later, it did it again, would crank but not start but this time it was daily, morning and evening for about a week. Each time it failed to start it was a waiting game, sometimes I would try it several times over the course of 10 minutes and it would start, other times I'd have to leave it for 10, 20, 30 minutes or sometimes an hour before it would start again. The garage coulldn't look at it for 2 weeks, but the 2nd week before it went into the garage, it didn't do it atall. I scanned the car and the code was P019100 active/static fuel rail pressure sensor 'A' circuit range/performance.

As this was the first time I'd had it in the garage, they initially thought it might be HPFP but checked and there were no signs of any metal filings. It was diagnosed as a faulty fuel pressure sensor (one next to cambelt) and replaced with a Febi unit. The fuel filter was dated 2011, so it had never been changed and car was 12 years old at that point, so they changed it.

For about a year, had no starting issues then out the blue, the same crank but no start appeared again with the same P019100 code, exactly as before and again a waiting game to get the car started. Back to the garage it went and the garage again checked the fuel filter for metal filings, but again all ok. Once again, they suspected the fuel pressure sensor that had already previously been replaced with a Febi unit. This time they fitted a genuine VW one and they put in a warranty claim for the Febi one, which was honoured.

Anyway, about 3 months after having the genuine VW fuel pressure sensor fitted the crank no start happened again. Yet again, the same P019100 code, so back it went to the garage. This time they diagonosed a faulty fuel pump under the rear seat and put a Bosch one in which was £300 with labour.

You guessed it, a week later, it happened again. This time I didn't bother to wait for an hour to see if it would start, I just called the AA out. Anyways, they arrived and it wouldn't start, they didn't diagnose it as it was about 1am at this point, they towed me to the garage I use and I left it there. However, when the towbar was unhooked, I tried it and it started straight up! I chose to leave the vehicle at the garage to get it looked at next week as its become too unreliable now for me to use or trust.

Disregard the oil pressure light coming on, it doesn't usually do that as I don't usually crank it that long, I was doing that because I was cranking it hard in a last ditch attempt to get it to start, before calling the AA out.

I have very little confidence in this car now. For the last 2 years of ownership out of the 2.5 years I've had the car, everytime I get in it I am thinking will it start and I am sick of it now.

Has anybody experienced something similar? The rev counter isn't movnig when it cranks, could it be an immobiliser fault cutting fuel, so they even have an immobiliser?

Any advice appreciated.

[1.4_tsi]

I'm not familiar with the wiring layout, but given the fault is consistently associated with the P01910 fault code, and you have replaced the fuel rail pressure sensor the fault code relates to, the next most likely culprit is the wiring between the pressure sensor and its ecu. So I'd be checking the integrity of the wiring harness and the connector at both ends. Unplugging and replugging the connectors several times can sometimes clean off minor surface corrosion on the contacts and resolve intermittent faults caused by reduced conductivity