Hi Guys,

 

I'm having an issue with my Mk1 VRS. It's got 150K on the clock and is mechanically very well looked after, however I've had an issue for a while I can't seems to shrug it off. 

 

I'm getting engine light on and read codes for "Injector Contribution/Balance fault" across 3 injectors (sometimes only 1 or 2, but mostly 3 at a time) and rough running/poor MPG - worst at 2K rpm. 

 

My first thought would be the injector loom, however I replaced it about 20K miles ago so I'm ruling it out for now (and I had a different error at the time when that went). 

 

My second thought was the HPFP so I replaced it with a second hand unit and although I thought I solved the issue, it came back shortly after. 

 

It's an intermittent fault - sometimes there for 1K miles and then disappears for 500 so now I'm 99% sure it's electrical. 

 

I've checked the connectors for the glow plugs and they seem fine

 

I've cleaned the contacts for the main round plug that goes into the injector loom

 

Changed the air flow sensor

 

However, the other day I changed the fuel temp sensor and the car ran perfect for at least 500 miles, but the problems back again. The loom and connector that goes into the fuel temp sensor doesn't look great - could this be the issue? Every time I have a fiddle I may have move it a little and it causes the issue to temporarily go away? e.g. when I changed the pump. 

 

I would have thought some other error would come up if it war related to fuel temp sensor/loom though....

 

any ideas/advice?

 

Car starts fine and I can still use it day to day even when I have the issue. I reckon I loose about 15bhp and drop 10mpg. 

 

 

 

Dyfi,

 

What is the code?

 

SN

Dyfi,

 

Googled the fault description you gave and found this:

 

- Dirty Fuel Injector
- Faulty Fuel Injector
- Plugged Fuel Injector
- Fuel injector harness is open or shorted
- Fuel injector circuit poor electrical connection

 

SN

according to that its either the injector loom or injector

I thought it unlikely to be injector issues as it's intermittent and not likely for all three to fail. 

 

Would the loom really go after just 20K miles though? 

 

Here's some vcds info if it helps. One where there were no issues, and one where it gone bad. 

 

 

Codes I get were PD Unit Injector: Cylinder (1, 2 and 3): Regulation Range Exceeded

 

 

I'm actually thinking it might be the loom from the injector loom back to the ecu? 

I thought it unlikely to be injector issues as it's intermittent and not likely for all three to fail. 

 

Would the loom really go after just 20K miles though? 

 

Here's some vcds info if it helps. One where there were no issues, and one where it gone bad. 

 

 

Codes I get were PD Unit Injector: Cylinder (1, 2 and 3): Regulation Range Exceeded

 

 

I'm actually thinking it might be the loom from the injector loom back to the ecu? 

it sounds that way and its your cheapest option go with loom first m8