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akrockhound
05-10-2009, 04:36 PM
Help, my '01 Disco II engine is missing when I climb hills. Feels like bad gas but it has been doing intermittently for months.

Trouble is I am not getting any codes so it is difficult to know what to do about it.

I would think that any ignition-related misses would through a code.

I would think the cam sensor would notice virtually ANY miss and throw a code - but nothing.

My question is what could it be?
I have a new set of Magnecor wires and platinum plugs on hand but haven't put them in yet.

Could it be a fuel injector? would that throw a code?

Could it be the transmission slipping slightly giving the feel of a miss?

Could it be the Mass air flow sensor? would that throw a code?

Could it be an air leak somwhere?

Any thoughts would be helpful

Les Parker
05-11-2009, 09:23 AM
Any idea how long ago the plugs/wires were replaced?
Have you taken the spark plugs out to see their condition?
Also have you checked the fuel pressure? Could be a sign of a failing fuel pump.

akrockhound
05-11-2009, 07:17 PM
how/where do I check the fuel pressure and what should it be?

I have not checked the plugs...thinking that if there was an issue there that it would throw a code.

galant344
05-11-2009, 11:34 PM
to check the fuel pressure you will need a guage that has a screw on type fitting. not sure of the size. between the back of the intake manifold and bulk head there is a cap, like a tire valve cap. remove that and install your guage.
i believe the fuel pressure should be around 50 psi. to access this outlet you might have to unclip the wiring harness that runs along the edge of the bulk head. its a tight spot but if you look slightly to tie driver side behind the intake just over the coils you should see this silver cap/outlet for checking fuel pressure.

hopefully this will help

akrockhound
05-13-2009, 11:43 PM
Thanks for the info on checking the fuel pressure.
Since the last post I did changed the spark plugs to platinum 4's. The gap on the old plugs was about 3x the specs. I also noted on two plug wires alot of corrosion on the metal clip that connects to the end of the spark plug (those plug tips were grayer than the rest too). It helped, the car runs smoother, but there is still some missing going up hills. Next step is to replace the wires with 8mm Magnacors and then check the fuel pressure if the wires don't fix it.

I am still surprised that I am not getting any codes with the misses...that would get me right to the bad cylinder (s) if it was a wire problem.

rovertek
05-14-2009, 04:34 PM
if its fuel pressure reated you will not get codes, the pump needs to have at least 20 psi in order for the injectors to work when the fuel pump falls below that 20 psi (say 17-or 18) the engine will still run but will not supply the amount of fuel needed on demand going up hills or pulling a load ext. replace pump but check press regulator first.....

akrockhound
05-15-2009, 12:24 AM
Ok I found the fuel pressure port....can someone describe the type of guage I need to get onto this fitting?

Is it something I might buy at Napa..is it available at Rovers North?

akrockhound
05-18-2009, 11:27 PM
I installed the magnecor 8mm ignition wires this weekend and the engine missing is gone.