Help needed.New 2003 Transit owner query

[D.Owens]

Hi there, I’ve searched the forums but can’t find posts that match my needs.
The van has 125k miles. Drives fine, always starts, never stalls. Recently serviced, new oil etc.
Sometimes when starting up the oil warning light stays on for about
minute. Doesn’t happen every time. Oil level is full.
The other day the glow plug warning light started flashing.
No loss of power. Have driven it loads since and it hasn’t come on
again.
Took to Kwik fit to get codes read (as my code reader wouldn’t
work; nor works my neighbours). Threw up codes
p1631 main relay open circuit and p1664 injection pump
malfunction.
Asked my local garage who serviced it and was told if the
glow plug warning light comes on again, or oil light stays on
tell him.
What I’m hoping to avoid is the van suddenly losing power, so
is there a preventative measure they can be done now?
Could the main relay open circuit fault p1631 be causing the p1664 injection pump
issue?
Has anyone else had these codes come up
without the van losing power and with no starting issues
or smoke etc?
Any advice about preventing further issues would be great. Also which
jobs can be done at home!
Cheers
Dave

[knobby1]

Hi there, I’ve searched the forums but can’t find posts that match my needs.
The van has 125k miles. Drives fine, always starts, never stalls. Recently serviced, new oil etc.
Sometimes when starting up the oil warning light stays on for about
minute. Doesn’t happen every time. Oil level is full.
The other day the glow plug warning light started flashing.
No loss of power. Have driven it loads since and it hasn’t come on
again.
Took to Kwik fit to get codes read (as my code reader wouldn’t
work; nor works my neighbours). Threw up codes
p1631 main relay open circuit and p1664 injection pump
malfunction.
Asked my local garage who serviced it and was told if the
glow plug warning light comes on again, or oil light stays on
tell him.
What I’m hoping to avoid is the van suddenly losing power, so
is there a preventative measure they can be done now?
Could the main relay open circuit fault p1631 be causing the p1664 injection pump
issue?
Has anyone else had these codes come up
without the van losing power and with no starting issues
or smoke etc?
Any advice about preventing further issues would be great. Also which
jobs can be done at home!
Cheers
Dave

Firstly, which engine do you have..?? FWD or RWD..?? And which PS..??

Mk6 Transits are NOT OBD-II compliant, so most of the newer readers won't work. Most of us use Forscan on a laptop and a modified ELM-327...works for all Mk6 and later Transits.

Mk6 glow plug light also doubles as the DTC/fault light. When it flashes fast it will log a fault code.

P1664 is often the fuel pump contol module starting to fail, commonly known as the EDC unit which lives on the pump. Your engine will have either a VP-30 or VP-44 fuel pump on it depending on the PS rating. These can be repaired...or just replace the entire pump, but this is expensive.

P1631 is possibly a poor main relay or the wiring to/from it is not well.

With the oil light staying on, could be a duff oil pressure switch, you can test the oil pressure at the engine to find out if the switch is faulty..... when was the oil & filter last changed.??

Lord Knobrot