Mk7 poor starter.

[MinorMatt]

Ok new thread to carry on from this. Its not EGR so new thread to get title right

MK7 '56 plate 2.4 100PS RWD.

I bought it a few weeks ago, as a poor starter.

With easy start it eventually goes - but smokes (white) at idle, white as you drive it, and a mix of white and black when you hoof it. Might be slightly underpowered, but not sure.

The only code that comes up (not at idle, but only when driving) is camshaft position sensor.

Crank and cam sensors sync - but only when a little throttle is applied.

Any thoughts?

(Previous thread - viewtopic.php?f=5&t=224797)

[tranmx2]

worn chain

[knobby1]

Ok new thread to carry on from this. Its not EGR so new thread to get title right

MK7 '56 plate 2.4 100PS RWD.

I bought it a few weeks ago, as a poor starter.

With easy start it eventually goes - but smokes (white) at idle, white as you drive it, and a mix of white and black when you hoof it. Might be slightly underpowered, but not sure.

The only code that comes up (not at idle, but only when driving) is camshaft position sensor.

Crank and cam sensors sync - but only when a little throttle is applied.

Any thoughts?

(Previous thread - viewtopic.php?f=5&t=224797)

Does she have cam chain rattle when cranking....and when she does eventually start when cold..?? A slack cam chain can give similar hard to start symptoms until the oil pressure comes up and the cam/crank sync is pulled back into spec. If the cam/crank sync is out during cranking it will never start till the oil pressure brings it back.

Lord Knobrot

[MinorMatt]

No chain rattle...

It will sync immediately with throttle pressed even when cold.

When nice and hot, it wants throttle to start too

[ned]

I still think it’s an injector fault


Just out of curiosity which end is the prv on the rwd? If it’s at the back I’m wondering if it or the pipe to it has been damaged changing the egr, just a thought

[knobby1]

I still think it’s an injector fault

Just out of curiosity which end is the prv on the rwd? If it’s at the back I’m wondering if it or the pipe to it has been damaged changing the egr, just a thought

FYI Matt...pushing or pumping the throttle on a Mk7 does absolutely nothing during cranking/starting, they're fly-by-wire and the pedal isn't enabled by the PCM until a stable idle of ~800rpm is achieved.

On the RWD the PRV is at the rear end of the fuel rail, it's done up to a silly torque too, (firstly 30nm to seat the shim/washer, then another 3mm and/or 172nm final torque), the plastic line coming from it towards the rear is just a drain/return line, there's no pressure in it, you can remove the line and it would have little to no effect on the running of the engine other than allowing air into the low pressure side of the system, it's a joint line with the injector leak-off return lines....if the PRV was blown, the engine would never start.

The front end of the fuel rail has the rail pressure sensor with electrical connector fitted....it's normally not available separately from Ford unless you buy the complete rail assemmbly....they rarely fail though.

https://www.catcar.info/ford/?lang=en&l ... EzMw%3D%3D

Lord Knobrot

[MinorMatt]

I think its likely an injector issue too.

Given there are no DTCs - whats the best way to work oit which one it is?

Appreciate throttle doesn't do anythibg... but not sure why crank and cam will only sync when throttle is pressed!

I am very temped to get an injector in - even if I don't need it now I probably will in the future!

[ned]

A leak off test should show a duff injector, think the test is 4 minutes at idle, 25 - 40ml is acceptable irrc,

[MinorMatt]

Leak off test...

No.1 on the right, no 4 on the left.

It managed 2m 15s at a hot idle before it coughed and died (leak off returns not capped)

1 - 35ml
2 - 30m
3 - 40ml
4 - 37ml

Oh wise forum members - what does this mean????

[MinorMatt]

Well thats a bit interesting.

Whilst I was there I pulled the cam sensor out, gave it a quick wipe and put it back...

After all the cranking to bleed it back through it was still as rough as a badgers rear end.

I unplugged the cam sensor and it was the same, plugged it in again and a few seconds later it settled down.

Went for a quick hoof down tne dual carriageway and it chucked out a massive amount of smoke when flat to the floor, some cars behind and I lifted off - then it wouldn't do more than 40 in 4th. Shortly after I booted it again and it picked up really well with no smoke. Got back and the idle is the best its been, the needle on the rev counter is steady.

Its now being left to see if it starts ok tomorrow.

My thoughts are now cam position sensor, or the wiring/plug for it...

[metalworker0]

what's the mileage - perhaps its time to take the manifiold off and give the ports and valves the wallnut blasting treatment.

all the best.mark

[MinorMatt]

189,000 miles

I don't think thats whats causing the issues tbh

The EGR is now blanked (but not mapped out)

Will be interesting to see what happens when I have a play tomorrow

[knobby1]

189,000 miles

I don't think thats whats causing the issues tbh

The EGR is now blanked (but not mapped out)

Will be interesting to see what happens when I have a play tomorrow

It will probably throw a MAF & MAP sensor fault code when you blank the EGR valve and it's not mapped out. Mine did.

Lord Knobrot

[MinorMatt]

189,000 miles

I don't think thats whats causing the issues tbh

The EGR is now blanked (but not mapped out)

Will be interesting to see what happens when I have a play tomorrow

It will probably throw a MAF & MAP sensor fault code when you blank the EGR valve and it's not mapped out. Mine did.

Lord Knobrot

Thats what I am expecting - but blanking it off has cut off a variable related to starting now

[MinorMatt]

And no.... its back to non starting