Won't idle cold or hot

[Dartmoor7]

1994 1400 Supersport no mods, Vecta immobiliser.

Three days ago the car was running perfectly.

Then I left the ignition switched on and drained the battery.

Recharged and refitted today.

The engine will start if I give it a little bit of throttle, but won't start without it.

Even when fully hot it won't continue to run without a tickle of throttle.

Have tried the MEMS reset routine, no effect.

Am I doing it right?

Vecta key/ignition on/press accelerator five times/ see the IACV adjust itself/ turn ignition off/

then is it start immediately or wait and go through the Vecta stage again?

Help, I'm missing the sun!

Thanks.

 

 

Jerry Parker

L7 SVN

1.4 Supersport

[conorkaby]

From past experiance it would be wise to check your battery out as a first step. My 1.6ss developed a misfire under load which was rectified with a new battery. A quick peep at the cells revealed buckling and sediment.

 

[Dartmoor7]

It runs and performs absolutely perfectly, except it won't hold idle, it just stops running.

 

Jerry Parker

L7 SVN

1.4 Supersport

[Strangely]

IACV? Coolant temperature sensor? There's an old thread covering both here:

http://blatchat.com/T.asp?id=76211

 

You should be able to simply check each by pulling the relevant connector off and seeing whether that changes the symptoms.

[Dartmoor7]

I'll take a look but doesn't really match my symptoms, in that mine stalls cold or hot, the engine temp makes no difference whatsoever, even though I can see the IACV adjusting itself when I do the reset procedure.

 

Jerry Parker

L7 SVN

1.4 Supersport

[Ian_Brandon]

 

I had this kind of problem quite recently and after chasing down various red herrings it turned out to be simply a bad crimp in the wiring. If you have messed about/bent back the battery connections maybe you have disturbed a delicate connection. Just a thought.

 

VVC + DVA = FQ

[Dartmoor7]

OK, to get back to basics, all other things being equal, with everything in working order, why would a 1400 Rover be unable to maintain idle when hot?

 

Jerry Parker

L7 SVN

1.4 Supersport

[micksmetafors]

My VVC had exactly this problem. Needed throttle to run after initial firing.

 

I was told by CC that the ECU doesn't see enough volts from the battery and shuts itself down.

 

A new battery was the only solution.

 

If you jump start it it will run normally with the old battery even after disconnecting the jump leads.

 

Sadly looks like you'll need to spend £50.

 

 

[Dartmoor7]

Battery fine, 12.6V no load, 10.5V cranking.

 

Jerry Parker

L7 SVN

1.4 Supersport

[Dartmoor7]

I have got the car running now, by adjusting the throttle stop screw on the throttle body; but as this has a locknut I don't see how it could have 'un-adjusted' itself in the first place, so I am slightly concerned that I am treating the symptom not the cause.

I have been studying the Haynes manual for Rovers and because my car is a very early KSS it seems to have the throttle body from the 2 litre O-series (?) engine rather than the standard smaller K's, which means it doesn't have an IACV, it has a stepper motor arrangement.

 

 

Jerry Parker

L7 SVN

1400 Supersport

 

Edited by - L7SVN on 25 Jun 2005 16:17:42

[paul jacobs]

Any further luck in getting your car to idle Jerry?

I'm still having trouble with my 1.6Ss K, even after messing around with the throttle stop, it sometimes dies away to nothing when pulling at at T junctions and the like I can't help thinking that it is in the mapping, which on the MEMS is out of bounds, and I don't wont to buy an emerald at this stage...........

 

Paul J. Hard work never killed anyone ........ but why take the chance!

[Dartmoor7]

Hi Paul,

It's running fine with the throttle stop adjusted, done over 100 miles 'testing' on the moor.

Still bit concerned I've cured the symptom not the disease, but can't understand how the throttle stop could have loosened/adjusted/retightened itself.

If I get no further indications of trouble, I'll leave it until its next service with Mike Brend and see if he has any ideas.

 

Jerry Parker

L7 SVN

1400 Supersport

[Dartmoor7]

Paul, re your stalling, when you fitted the SS cams was there a different ECU to go with it?

Did SS cars get a tweaked MEMS originally?

Not sure but almost certain they did.

 

Jerry Parker

L7 SVN

1400 Supersport

 

Edited by - L7SVN on 28 Jun 2005 05:54:32

[paul jacobs]

Yes, CC did fit a remapped ECU with the cams, which I fitted when the new cams went in, which is when the dam thing stopped idling sweetly, which makes me think it is something in the mapping.

When / play with the throttle stop, it will either end up idling at 1500rpm or down to a very lumpy 900, then tend to die when allowed to drop revs naturally, junctions and the like.

[Dartmoor7]

If you set the throttle stop for 1000 rpm when engine hot, will it maintain this idling speed for as long as you run the engine?

I'm sure some people have done this and disconnected the wires to the stepper motor or IACV.

Not sure what happens when cold but at least you'd have a car that worked when hot.

 

Jerry Parker

L7 SVN

1400 Supersport

[paul jacobs]

It will hold this idle if I don't drive it, but as soon as I get into the real world, unless I actually give some gas on the acelerator pedal, it will die the death, it's as if the map isn't giving it enough instructions to hold onto the 1000rpm idle when dropping down from higher engine speeds. I could disconnect the IACV and see what happens, Frankly, I'm not too worried about how it runs when cold, because it soon heats up and it is a real PIA for the rest of the time, At the mo. it is perfect when cold!

[mav]

Mine used to drop away occasionally pulling up at junctions.

 

Not done it since fitting Verniers and getting the cams timed properly - and that is on a 1.6K SS mems...

[oilyhands]

Just a thought..

 

If the new ECU is from a model with an IACV then that may be the problem, twhen you exchanged the ECUs he idle stepper motor may have been frozen in a position that provided enough air for a good hot and cold idle, the battery disconnection may have caused it to initialise itself. If the ECU doesnt have logic to control the stepper motor then on subsequent starts it may not move from it's initial position.

 

Oily

[Dartmoor7]

Oily,

Think you are confusing the two separate cars in this thread: my 1400 SS is the original thread 'won't idle hot or cold' and has not had any changes to it other than a flat battery; Paul's car was a 1600, then he fitted a Supersport kit, now he has this:

 

It will hold this idle if I don't drive it, but as soon as I get into the real world, unless I actually give some gas on the acelerator pedal, it will die the death, it's as if the map isn't giving it enough instructions to hold onto the 1000rpm idle when dropping down from higher engine speeds. I could disconnect the IACV and see what happens, Frankly, I'm not too worried about how it runs when cold, because it soon heats up and it is a real PIA for the rest of the time, At the mo. it is perfect when cold!

 

Jerry Parker

L7 SVN

1400 Supersport

[oilyhands]

Err Sorry, maybe a more meticulous read would have helped.

 

However, it may mean the the stepper motor was stuck in the open position prior to the battery flattening and has since died...

 

Oily

[Dartmoor7]

I can see the stepper working and I have got it idling acceptably by adjusting the throttle stop, which may be treating the symptom not the disease but will do for now.

I'm sure Paul would be grateful for the application of your knowledge to his problem which has been ongoing for some time now.

 

Jerry Parker

L7 SVN

1400 Supersport

[paul jacobs]

Sorry to confuse you Dave, I wasn't trying to highhack Jerrys thread, honest 😳 Mav, it sounds like yours was doing just what mine is, I have had verniers installed and retimed too, but all to know avail.