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Discussion Starter #1
Hello all.
This is what is going on with 1990 County with 3.9L

She starts up very easily. don't have to do anything but turn the key.

There is a very slight hesitation when I pump the pedal in neutral just at the beginning.

I put her in gear and she has very little power.
The symptom is this. She does gain power more and more as I pump the pedal. Full throttle and the power stays the same. Only gains when I pump the accelerator pedal.

What would cause that?
I just replaced the injectors (it was doing the same thing prior)

Thank you all for your help
 

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When was the last time you checked your timing? How old is your fuel filter? original fuel pump? possibly low fuel pressure due filter or worn out pump. it all sounds like weak fuel delivery or weak ignition.
 

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Discussion Starter #3
The Rover is new to me, so i am not sure.
I plan to change all of that eventually, so you could be right.
The more I work on this engine, the more I realize that I should just replace every component
 

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im With RRTH, it does sound fuel related, Once you’ve checked the fuel pressure, check the sensors, ( throttle) clean the throttle body, eliminate things rather than just throwing parts at it, it will become a money pit otherwise
 

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Discussion Starter #5
I had to order a fuel pressure gauge today. Small town here. Easier to order instead of drive an hour.
I did a visual test. The pump seems to push out a good strong stream.
I installed a new filter.
There is no change. Of course I will check the pressure when the tester gets here.
It seems very strange that pumping the pedal is actually like my foot is pumping more fuel in.
Without being able to test the pressure at the rail, how do I know if it is the regulator or not?

Thank you
 

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to original question, what problem do I have? its a land rover. not much you can do visually, can't tell pressure by volume, can't judge volume
thus basically you need test equip.
best of luck.
 

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Discussion Starter #8
Fuel pressure gauge arrived today. Here are the readings
35 @ ignition turned
35 while the car is running
27 when key is off and it holds there

What to check next?
How do I know if regulator is bad?

Thanks all
 

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Several possibilities come to mind, all related to fuel delivery, as previously brought up. I am not sure whether the fuel pressure is correct, but I would need some further info to help. First, I have seen some of these vehicles, not just Rovers use a lean mixture at cold startup to load O2 into the catalytic converters. If others would chime in here regarding this matter, it would be appreciated. Knowing the fuel trim numbers, both long term and short term, that would help. The system uses the O2 sensor, when in closed loop to set these trims, and if the system is rich when warm, the fuel trims would reflect this. How does this affect the matter being discussed? If the fuel trims show a dial back due to rich mixtures when warm, the reduced fuel will affect cold operation, creating lean cold mixtures. These numbers will also help diagnose a potential fuel pump issue as well, as the trims will show fuel being added as the pressure drops. Knowing these numbers is a good place to start. Ray
 

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Discussion Starter #10
I will have to look into how to test trim

Could an old battery possibly do it? I believe it has plenty of charge as the engine fires right up.
Just a thought as it was dead when I bought the Rover and then I charged it and it is holding a charge
 

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Do you have good exhaust flow? The behavior you are describing (good idle, won’t take throttle) is a symptom of clogged catalytic converters or obstructed exhaust.
 

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I've got a adjustable FPR on my rig with a gauge, the pressure must be really off if it wants to effect the running of the engine.
When the pressure is low you know the difference a bit when driving, but when it's too high, you hardly notice it...
 

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I had this *exact* problem, I can't remember how I fixed it, but it wasn't related to fuel delivery.

These thoughts come to mind..

1) Disconnect the MAF and the O2 sensors. See if you still have the problem
2) Check to make sure the Ignition coil is working effectively. (ie. has good electrical connection)
3) Test the Throttle position sensor.

I'm leaning towards it being #3.
 

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I'm sure you've checked, but how much play in the throttle do you have? Sounds like the issue I had on a GDE. It was the throttle adjustment that had nearly completely unspun. Stupid problem, easy solution, totally overlooked and the last thing I thought of. Good luck.
 

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Discussion Starter #16
I will for sure take a look at that.
I just changed the cap and plug wires. Then redid the timing and it runs much better.
Although, when I am going up a steeper hill and I have my foot to the floor, it does not do well until I pump the accelerator.
 

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Discussion Starter #18
kinda
I had a second one that looked a lot better than the one installed. It didn't change but that is not to say that it was bad either.
Is there a way to test it?
 

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‘Although, when I am going up a steeper hill and I have my foot to the floor, it does not do well until I pump the accelerator.’

Ok – lots of information lost in translation… Is your throttle response issue stationary - non driving?

If not ….

You have a transmission ‘kick-down’ cable that may need adjustment. It is just to the right of the throttle cable – adjust it tighter; a few clicks at a time and drive.
 
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