Freelander 1 high idle speed

Hello all, I am searching for ideas how to cure some problems I have got with a 1999 petrol freelander 1.8.
I'm in norfolk and just got this vehicle. I should probably say that I have owned many landrovers over the years and currently run: a 200 tdi J Reg defender-pretty original except the back axle which now is a disc braked disco conversion : a 300 tdi disco as a daily driver : and a series 3 swb station wagon in the shed in bits ready for a rebuild.
The freelander was fairly cheap otherwise I wouldn't have got it as never having owned one I've always been a bit dubious about them as "PROPER" landrovers especially with the drive train problems. My one has got round this by having the whole lot taken away by a previous owner- probably no bad thing as I won't be going off road with it anyway.
Anyway all that aside the engine idles at just over 1000 which seems a bit high- can anyone tell me if I am missing a trick here because if I restrict the air flow to the idle control valve I can bring the idle speed down to a better level. Does this valve only control idle speed because if so then a restrictor on the pipe will cure it...........or not?
thanks

The IACV is there for idle control only. They do stick and so need cleaning and lubrication. There could also be a split in a vacuum pipe or a split in the servo diaphragm.

thanks for the reply, yes I have had it apart and cleaned it, it was pretty sooty inside but made no difference.With the hose disconnected it makes no difference either unless i put my finger over the end of it to restrict the air flow, then the revs drop so i guess the unit is actually working. Is it dependent on the air flow through the air filter assembly , there doesn't seem to be any other way to control it?
I wouldn't be all that bothered but I think the ABS and HDC warning lights are coming on because of this.

Rodeo Joe said:

thanks for the reply, yes I have had it apart and cleaned it, it was pretty sooty inside but made no difference.With the hose disconnected it makes no difference either unless i put my finger over the end of it to restrict the air flow, then the revs drop so i guess the unit is actually working. Is it dependent on the air flow through the air filter assembly , there doesn't seem to be any other way to control it?
I wouldn't be all that bothered but I think the ABS and HDC warning lights are coming on because of this.

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The IACV is the only way the ECU controls the engine speed, along with a small, factory set air bypass through the throttle plate.
Has someone screwed the throttle plate stop screw in more than its factory setting? Sometimes owers "fiddle" with things that shouldn't be touched. Try backing the throttle stop screw out a turn at a time, to see if it makes a difference to idle speed. Also make sure the throttle cable has 10mm slack at the pedal.
Otherwise air leaks into the inlet tract that bypassing the throttle plate will cause high idle speeds.

The HDC/ ABS lights aren't related to the idle speed issue. You'll need a diagnostic device to tell you the cause of the lights.

Thanks I'll check the throttle screw tomorrow . I was told by a garage that the HDC/ABS lights were because the idle was fast and the ECU was thinking the wheels were not turning the speed that it thought they should be.

Rodeo Joe said:

Thanks I'll check the throttle screw tomorrow . I was told by a garage that the HDC/ABS lights were because the idle was fast and the ECU was thinking the wheels were not turning the speed that it thought they should be.

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lol, I hope you're not going to be taking the car there any more.

What age is your Freelander? Early cars will be like all other Rovers/ MG of the time, and come fitted with a plastic throttle body. These are terrific, but if someone has replaced the standard clip that retains the air trunking to the air box with a Jubilee clip with a worm drive, over-torqueing distorts the throttle body leading to a fast idle owing to a residual air leak.

There are multiple other causes too - again, on early MEMS1.9 cars (pre-2000), the ECU's water temperature sensor can be faulty, leading to the engine ECU "thinking" the engine is cold - which in turn leads to a cold (fast) idle.

Those would be my first two ports of call here

Its a 1999 model, I'll check the clips and hoses. I cleared the fault codes today with a hawkeye total, all the amber lights have gone except the ABS which stays on despite there apparently being no faults! Any ideas?

Does ABS go out when you drive over 4mph, or stay on?

1999 was a watershed year for MEMS conversion from 1.9 to 3 - but I think you'll have the plastic throttle body and the water temperature sensor is certainly worth looking at. If your fault code reader can read the engine ECU, look to see whether the water temperature looks appropriate on the live data.

I didn't know I had to drive it for the light to go out. I'll check it later thanks.
I put a clip on the air inlet pipe to the manifold (I presume there should have been one) now it slows down a bit when warm, not perfect but better. The hawkeye tells me the idle is erratic but not whats causing it ...it would be a much better bit of kit if there was a comprehensive 'how to guide' for it rather than finding snippets of info here and there. It might be a good subject for a section of its own on this forum.
I might find out how to plug it into my 1991 Defender

Only an air leak can cause a fast idle - the engine needs air to run faster. That air leak my be "intentional" through opening the throttle, or through operation of the IACV (as can happen when the ECU thinks the engine is cold and is "opening the choke"). Or it may represent a physical leak - a disconnected pipe to the manifold, or a manifold that is not sealed to the cylinder head.

Uneven idle may be related or unrelated - might be useful to see what the live data feed shows?

The temperature sensor showed the coolant heating up, I haven't left it long enough to get up to full temp it got to about 55 deg- what is operating temp for a K series?
This may be a daft question but does the air flow for the IACV go to or from the airbox, the small pipe to the airbox has no clips although it seems quite a tight fit anyway it doesn't fill me with confidence

Rodeo Joe said:

The temperature sensor showed the coolant heating up, I haven't left it long enough to get up to full temp it got to about 55 deg- what is operating temp for a K series?
This may be a daft question but does the air flow for the IACV go to or from the airbox, the small pipe to the airbox has no clips although it seems quite a tight fit anyway it doesn't fill me with confidence

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The K series running temperature is about 85 to 90°C.
The IACV has an air connection to each side of throttle plate. It basically passes all the air needed to control idle speed. You're uneven idle could be related to an air leak. Check for splits or air leaks in the brake servo pipes. Also listen for an air leak from the servo. This can sometimes be heard by sticking an ear by the brake pedal.

Well the good news is the ABS light went out as soon as I moved the landy this morning. The bad news is I did a live data check and the temp went up to 81 deg and the binnacle gauge didn't budge. The heater shoved out warm air though so does that mean the coolant temp sensor is faulty ? I don't know where the ECU gets its data from. Like you said it might be the cause of the high idle, I'll get a new one ordered.

Rodeo Joe said:

Well the good news is the ABS light went out as soon as I moved the landy this morning. The bad news is I did a live data check and the temp went up to 81 deg and the binnacle gauge didn't budge. The heater shoved out warm air though so does that mean the coolant temp sensor is faulty ? I don't know where the ECU gets its data from. Like you said it might be the cause of the high idle, I'll get a new one ordered.

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There are 2 coolant temp sensors. 1 does the gauge and the other is for the ECU. Your ECU sensor is working, the dash one isn't.

Check for air leaks for the idle issue.

A

Rodeo Joe said:

Well the good news is the ABS light went out as soon as I moved the landy this morning. The bad news is I did a live data check and the temp went up to 81 deg and the binnacle gauge didn't budge. The heater shoved out warm air though so does that mean the coolant temp sensor is faulty ? I don't know where the ECU gets its data from. Like you said it might be the cause of the high idle, I'll get a new one ordered.

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ABS light will stay on until you reach 6mph if it's like the other landy systems.

Is the sensor for the gauge the one on the thermostat housing? I'm not used to all this electronic trickery, I always said I'd never have a post 1998 landrover, I should have stuck with the Tdi's, with the exception of the immobilizer on the disco its all pretty straight forward

Rodeo Joe said:

Is the sensor for the gauge the one on the thermostat housing? I'm not used to all this electronic trickery, I always said I'd never have a post 1998 landrover, I should have stuck with the Tdi's, with the exception of the immobilizer on the disco its all pretty straight forward

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TBH there's not a lot of electricery in a F1 - especially a '99, it probably won't even have electric back windows. What electrics there are is fairly simple and does make them pretty reliable and safe - eg the EMS, ABS and SRS. The biggest problem (or at least one of the biggest!) is the fact that the (few) ECUs are coded together and the diags is pretty proprietary - and that's a couple of problems already

Wait till you consider an F2 or later with their umpteen data networks that decide the engine needs to be turned off because you're wiper switch has an intermittent problem.

Rodeo Joe said:

Is the sensor for the gauge the one on the thermostat housing? I'm not used to all this electronic trickery, I always said I'd never have a post 1998 landrover, I should have stuck with the Tdi's, with the exception of the immobilizer on the disco its all pretty straight forward

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Both sensors are on the coolant outlet elbow (hose to top of rad).

A 99 FL1 is very sparsely electrified compared to anything after 2000.

Yup, the electrical architecture on these cars represents the pinnacle of Rover electrical engineering - quite a few ECUs, but they generally don't talk much to each other, so that if one were to fail, everything else just continues to work just fine

Contemporary MGFs, Rover 200/25, Rover 400/45 and MG ZR and ZS are just the same