27 replies to this topic

[idlethumbs]

So I was watching the stepper motor this morning and it is working ok but it almost seems slow.
When letting off the throttle the stepper is completely in and so allowing the revs to drop off.
If the engine doesnt stall then within half a second the stepper moves out and puts the idle back to where it should be to keep it going.

My very limited knowledge of the stepper does that sound right?

[RooBoonix]

Is your throttle cable adjusted correctly?

Edit: infact, I don't think that would affect your issue on the spi system..

Edited by RooBoonix, 31 January 2018 - 02:41 PM.

[idlethumbs]

Yea adjusted correctly with the free motion link centered.

[MatthewsDad]

When you replaced the fuel filter did you also replace the bendy lines to and from the filter? They can rust badly around the subframe. Has a clump of rust dislodged which blocks the filter or fuel line under certain flow conditions? Bit random, just a thought.

[viz139]

Was the flywheel replaced? Could the timing ring be set incorrectly or even be wrong one(MPi) ?

[Fast Ivan]

do the throttle position and MAP sensor readings increase with revs?

[Sprocket]

Yea adjusted correctly with the free motion link centered.

 

 

Did you index the stepper motor before adjusting the cable?

To quote from one of the pinned topics
"To check if the throttle cable is adjusted correctly the IAC (Idle Air Control) stepper motor needs to be 'set'. This is achieved by turning the ignition to on but do not start the engine, then operate the throttle linkage to full open throttle. Do not use the throttle pedal as this will not work."

[idlethumbs]

Fuel filter lines were not replaced only the filter. Maybe a thought if I dont get anywhere else although the filter was replaced not long before the engine was done and it ran fine at that point.

Yes flywheel replaces but with the spi specific one. I am trusting the builders timing as reputable builder.

Fast Ivan I will check tmrw and plug back in.

Sprocket I adjusted the cable first making sure the lost motion was centred and butterfly opening and closing fully. Then indexed the stepper as per Haynes by hand not pedal. Then readjusted again.

[idlethumbs]

Morning fast Ivan

Yes both rose when blipping the throttle.
Map sensor jumps up to 80-100.
Throttle position jumps up anywhere from 2.5 to 4

Checked my throttle switch was opening as conscious I hadnt but all working ok.

[Fast Ivan]

Is it actually firing on all cylinders when at idle?
Is there a good spark from each of the leads?
Have you checked the timing?

[idlethumbs]

Yea firing on all 4.
Its actually seemed a lot better the last few days but thats only in a workshop. Not out on the road.
I wouldnt know how to check the timing :-(

Anyway my rover pod 3 arrived today for the ACR so will report back tomorrow after readings the stepper properly.

[Sprocket]

Please expand a little on your comments regarding the TPS voltage. When you say the voltage jumps from 2.5 to 4.0v under what conditions? without any throttle input?

I only ask as at idle, 2.5v seems quite high. If it then suddenly jumps to 4v and the throttle is not anywhere near full open, I think you might have a problem there.

[idlethumbs]

Sorry sprocket. I meant that was when I blipped the throttle. At idle it was much lower at around 0.5v. I believe that is about right.

Tried with pod 3 today.
2 issues, the first and main one was the permanent problems I have had seem to have completely disappeared. I think the car knew I was threatening the acr and decided to behave today!!

2nd was I did try reading the stepper but it seemed to get stuck reading it.
Tune stepper option on the acr. First asks to get to temperature so I did. Then it goes to a screen saying it is reading the vehicle and it didnt get any further.
It reads every other component fine and gives the data I supplied every time, but didnt like the idea of reading the stepper.
Maybe thats a clue to the problem???