3.9 with Hotwire injection - flooding

Stuball · Post by **Stuball** » Thu Jul 04, 2013 1:34 pm

Hi guys,

Pulling my hair out with this one!!!

Ok so engine is a 3.9 rover v8 running standard hotwire injection system Running green tune resistor
TVR cam (unknown model)
Standard Heads

So, i HAVE had this engine running, idled fine, drove ok (bit kangaroo-y whilst cruising but good otherwise) but it had a bit of a top end rattle. I had it apart, drained all the lifters, and readjusted the lifter preload as couple of pushrods were loose (I have used shims, i know they arent ideal but all the lifter preloads are within the 0.060 to 0.020)

Once i put it all back together it now just floods! I can get it started by holding the throttle open but as soon as I let off it just dies.

So far I have done the following:

Checked timing - currently at 8 degrees BTDC
Replaced Spark Plugs - using BP6ES
Checked fuel return line for blockage - all clear
All vac lines are connected as they should be
Tried winding the idle bypass screw all the way out - still floods

I got hold of a suitable cable and the rover gauge software:

Replaced TPS sensor as it was reading incorrectly
Replaced Idle air control valve as it wasnt moving (though was in the fully open position) The new one moves as it should
Checked AFM readings - all ok
Water and Fuel temperature senders are reading correctly
No fault codes

The only thing I havent looked at is the fuel pressure regulator.

Any other ideas before I go mad?

Stu

DEVONMAN · Post by **DEVONMAN** » Thu Jul 04, 2013 3:08 pm

If you had a couple of loose pushrods and you then used shims to set the preload this would make things looser.
OR did you have shims in before the problem?

Stuball · Post by **Stuball** » Thu Jul 04, 2013 3:35 pm

Oops lol, yeah had shims in before hand. Went next size down (smallest) which seemed about right.

Stuball · Post by **Stuball** » Thu Jul 04, 2013 4:35 pm

OK so out of curiosity i put the old shims back in, and voila, she runs

Can only assume that i didnt measure the preload right and what Tony suggested to me, that valves were being held open slightly

So looks like i need adjustable pushrods if im gonna get rid of this rattle

Stu

DaveEFI · Post by **DaveEFI** » Thu Jul 04, 2013 4:59 pm

The most common reason for over fuelling is a faulty CTS - but you said you'd checked that? Does it make a difference if you unplug it? With it working correctly, this would make the engine think it's cold and go to warm up fuelling. So if that makes no difference on a warm engine I'd suspect the wiring or whatever.

Stuball · Post by **Stuball** » Sun Aug 11, 2013 11:05 am

Well this issue has now come back and I am completely stumped

Engine is now fitted with adjustable pushrods, initial startup was spot on, ran smooth etc.

Took it out for a test drive, loads of power, no hesitation or kangarooing or anything like that.

When i came back and pulled up it just died. I cannot for the life of me get it to idle or start on its own, hot or cold. It will ONLY run/start if i hold the throttle open slightly.

I have the rover gauge program and have checked the following:

Coolant temp sensor is reading correctly
Fuel temp sensor is reading correctly
TPS reads ok from 0 to 100% throttle
The IACV is reading correct in the program and moves freely from fully closed to fully open (and is fully open when starting)
AFM is set at 1.1v CO adjustment
NO fault codes on ECU

Timing is currently at 10 BTDC

Yet it just floods everytime i go to start it, sods law just booked it in for its MOT now its being a pita

Help!!
Stu

Big woof · Post by **Big woof** » Sun Aug 11, 2013 12:30 pm

Check the spark isn't weak when you start the motor up mate sounds like its the symptoms off the ignition module failing. Also if you have played around with the air bypass screw then you would need to reset it properly using blanks on the manifold make sure that no air is getting into the engine via the bypass screw and set the base idle off the engine reconnect the bypass pipe and see what happens

ChrisJC · Post by **ChrisJC** » Sun Aug 11, 2013 6:22 pm

Is it definitely flooding?, or leaning out?

If the latter, it could just be an air-leak somewhere.

Chris.

Eliot · Post by **Eliot** » Sun Aug 11, 2013 6:54 pm

How do you know its "flooding" ?

Big woof · Post by **Big woof** » Sun Aug 11, 2013 7:52 pm

I'f the plugs are wet it could be a ignition module failing maybe. Or to rule out the bypass screw being too far in adjust the throttle cable to hold the throttle a little so the butterfly is held open if that happens then I would be looking at base idle settings first as if there is very little air getting in it won't tick over.
Plus as already stated a air leak can cause the problem.

Stuball · Post by **Stuball** » Mon Aug 12, 2013 12:34 pm

Thanks for all the replies!

Yes am positive its flooding, wet plugs and it stinks of fuel.
Shall attempted to reset the base idle and see what happens, will
also see what the spark is like.

Aside from that the fuel pump has now died so needs replacing, doh!

Stu

Eliot · Post by **Eliot** » Mon Aug 12, 2013 1:46 pm

Keep an eye on your oil - all that fuel could be getting into the sump destroying your oil and subsequently your bearings.

That's what happened to these - out of a 440 big block that had been cranked to death with a flooding 4 barrel carb -

Stuball · Post by **Stuball** » Mon Aug 12, 2013 1:59 pm

Cheers Eliot, will keep a close watch on it

Stuball · Post by **Stuball** » Tue Aug 13, 2013 2:57 pm

I think I may have found the problem.

The roverguage program wasnt showing up a fault code but noticed that the select fuel map was "0" which is limp home mode - very rich.

Bit of checking and found a dislodged pin on the tune resistor plug (green resistor) so it wasn't connected at all. Re connected and fuel map is now set to "2". Battery currently flat so will charge it up and see what happens.

thanks again for all the response!!

Stu

Big woof · Post by **Big woof** » Tue Aug 13, 2013 3:06 pm

That would do it make it run very rich and blow thourgh the fuel