Hi I have a B4000, V6 4.0L SOHC from 2005, it’s only done 115000km, but it blows blue smoke on start up and chews a bit of oil so I assume the rings are going. (pressure test psi in cylinder order 145, 130, 135, 145, 115, 120). But most importantly it is missing excessively and it has started going into limp mode randomly. You pull over and wait 5 mins then you get to drive off again until it does it sometime between 1 and 10 minutes later, unless you keep the revs above 2500rpm. It starts easily and I live in a warm climate, so don’t have to worry about cold starts. I have replaced the spark plugs, plug leads, coil pack and fuel filter. With no improvement, so I checked the air filter, cleaned the MAF sensor, cleaned and checked the air intake and throttle chamber, checked throttle position sensor. Checked for air leaks, found one and fixed that no improvement. Checked the EGR Valve and PCV valve. I pulled out the injectors, cleaned and sonicated them, all have nice spray patterns and when connected to the rail and held in with gaff tape I saw no leakage, replaced the o-rings. Tested the fuel rail pressure perfect, but the rail pressure kept dropping but this was due to the petrol escaping from the pressure Schrader valve, and when I finally eliminated the leak the Schrader valve sheared off, so I had to solder that closed. Then I bought an OBDII, whilst I can understand some of the measurements I couldn’t find any values for certain things like what should a MAF value be? I have assumed since both oxygen sensors give equal readings then it’s probably unlikely to be a fault there. And before I start throwing more money at it for MAF or new injectors I thought I would ask if anyone has any suggestions.



OBDII readings

CALC LOAD 20.6%

COOLANT (F) 176

ST FTRM1 -10.9%

LT FTRM1 -25%

ST FTRM2 -3.9%

LT FTRM2 -18%

RPM 1095

IGN ADV 31 (at idle 20, is that too much?)

IAT 91

MAF 1.28

ABSLT TPS 19.6%

OS SII 0.53V

ST FTRMII -10.9%

O2 S12 0.705V

02 S21 0.145V

ST FTRM 21 -8.9%

02 S22 0.69V



I noticed that the LT FTRM would start at 0 and then over a few minutes work their way up to -25% as the computer keep leaning it out, until the sometimes reach the max -25% in which case it would throw a code and go into limp mode.

So it throws codes:

L Bank too rich

R Bank too rich



I guess one real question is if I can’t see the injectors leaking, they could still be leaking more under the vacuum of a cylinder right? Or should I be looking elsewhere. Any suggestions? this one has had me stumped for months. Ps some knucklehead had put an LPG system in, which of course died years ago, so I got rid of the system and plugged the holes they drilled straight into the manifold, but I still have to leave a few electrical leads connected to the computer to make it run.