Thread: 1989 RRC V8i - Cut Out

Auto or Manual mate ??

If you put a sudden big load on a 14CUX, the stepper sometimes cannot keep up.
If you held the steering on full lock then selected reverse in an auto, it will probably stall.
Mine has often stalled when shifting to reverse when hot as reverse is the lowest gear. I have to wait until the idle is completely stable.

It has done this with different steppers, IACs, MAFs, injectors etc so IMHO is a characteristic of 14CUX.
Regards Philip A

Thanks Guys, yes it is an auto. It's the first time it has done it in four years so gave me a bit of a surprise. And with the D3 off having the fuel pump replaced I got a bit worried.

Phillip, I'm not going to pretent I understand any of that, whats a stepper and an IAC? What puts the 'big load on'? Just looking to further my understanding.

Any cure or anything I can do?
Is it related to the power steering pump sounding like it's getting ready to give up? It was wierd that it seemed to cut out with steering input, even slight.

I'll check over all of the work I done last weeked to make sure i've not done anything daft.

The Idle Air Control valve, also commonly known as a "stepper" valve lives in the rear drivers side of the inlet manifold plenum chamber, and has a 4 wire plug on it. It controls the idle speed via the input from the vehicle ECU. This valve is known to get a bit sticky with age and can sometimes be cleaned successfully. Also sometimes the base idle setting may need adjusting upwards. You insert a 3/16 inch allen key in the little cavity above the air intake part of the manifold and unscrew the base idle screw by 1 turn or so. This raises the minimum idle speed the engine has under load.

Phillip, I'm not going to pretent I understand any of that, whats a stepper and an IAC? What puts the 'big load on'? Just looking to further my understanding.

stepper=Inlet air control valve (IAC) sorry same thing should have used the same word.
I recently had one apart and it is pretty problematic to clean them, as they have a screw thread inside which you cannot really clean. If you plan to buy a new one buy an OEM quality one as the I have bought a few cheapies now that have not been very good.
Otherwise as bee utey says.
When you put the steering on full lock , the pressure in it rises "a lot" and the engine may have trouble pushing the pump. You should never hold a hydraulic power steering on full lock for more than a few seconds.
Regards Philip A

Thanks guys, great explanations! What should idle revs be. I was just thinking a few days ago that since I put the new alternator in and the tachometer stopped twitching that 400rpm seems a bit low.

Originally Posted by TELF RRC

I have recently diagnosed a voltage drop across the firewall power stud which I seem to have sorted out by cleaning all the connections on the stud

Just to add to your list of things to check ......

That Stud is a Positive feeder ... I went to a Auto sparky with a list of all sorts of electrical problems, including engine woes. They changed (renewed) the stud and it sorted out all the electrical woes..... They mentioned that the stud was "internally" rusted

Have you looked at the cabin side of the stud and inspected the wires (4x brown wires) connected to it ... as mine were burned .... had to cut out the burnt lengths and re-extend to the post.

Cheers
Mike

Originally Posted by mike 90 RR

Just to add to your list of things to check ......

That Stud is a Positive feeder ... I went to a Auto sparky with a list of all sorts of electrical problems, including engine woes. They changed (renewed) the stud and it sorted out all the electrical woes.

Have you looked at the cabin side of the stud and inspected the wires (4x brown wires) connected to it ... as mine were burned .... had to cut out the burnt lengths and re-extend to the post.

Cheers
Mike

Yeah I looked at all the wires and cables both sides, all ok. Stud looked ok too as did insulators. Need to replace the battery to starter connector as it seemed to have melted a bit but enough to get it back on with good grip.