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Discussion Starter #1
Hi gents,
first post - hope this hasn't been asked before :) .

Anyway, got a Rover 214 8V 1999, 50k here.
When the car was purchased, there was a bolt shoved in the idle control stepper/solenoid pipe so it got no feed. I put this pipe back onto the throttle (unsure of why it was blocked anyway), and found that whenever you blip the throttle and the revs now stay sky high.

The (plastic) throttle body was removed and cleaned, and another 2 stepper motors were tried to no avail. The steppers were moving, and the throttle sealing properly.

Then mucking around with the pipes, I disconnected the pipe from the rocker cover breather, and suddenly all was normal. Which is great, but now the rocker cover's venting breather gases to air.
Anyone got any ideas as to what's going on - have I got some some mad blow-by issue? Could some other breather pipes be blocked up somewhere that are causing this (is there some around the back).

Cheers in advance.
 

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mg_zs
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There are 2 breahter pipes, one to the manifold and one to the throttle body. The one to the manifold may be blocked causing all the gasses ot vent throught the throttle body, affecting idle. Take them off and clean them out.
 

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Discussion Starter #3
sheddist said:
There are 2 breahter pipes, one to the manifold and one to the throttle body. The one to the manifold may be blocked causing all the gasses ot vent throught the throttle body, affecting idle. Take them off and clean them out.
Pipes are fine.

This is a conundrum for me. When I got the car I replaced a faulty thermostat (car engine had been running cold).

The stepper is fine and the throttle body is clean as a whistle now after cleaning it.

I checked the back pressure on another rover 214 and found that the car has the same amount of back pressure as mine when you take the oil cap off. This makes me think that the rocker air breather is not affecting idle after all.

Did a compression test on the Sat results are:

Cylinder 1 then 2 etc

Dry 14-12-12-12
Wet 16-14-14-14

I haven’t done any tests on the engine management system and no faults are shown on the dashboard. This is my next port of call.

Does anyone have an ideas why I might be getting the sticky throttle (2500 rpm) when all the breather pipes are connected up??

Could a faulty sensor do this??
 

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Discussion Starter #4 (Edited)
Oh and I should also add that fuel economy is poorer than it should be. Also blipping the accelerator does not cause the revs to fall back down to normal.
 

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Make sure that the vacuum pipe from the throttle body to the Charcoal cannister is properly connected and not leaking.
This can cause the revs to go a bit wild.
 

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Discussion Starter #6
I will check this out over the next day or so. Has anyone else experienced high revs which won't go down when you blip the accelerator. They stick at 2500rpm. Throttle body ok, stepper is ok.

Could a faulty engine sensor do this???

Appreciate anyone's thoughts on this
 

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mg_zs
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Seems like an air leak somewhere, or possibly:

Temperature sensor - engine thinks it is cold. Also check all underbonnet connectors and wiring.
 

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sheddist said:
Seems like an air leak somewhere, or possibly:

Temperature sensor - engine thinks it is cold. Also check all underbonnet connectors and wiring.
It won't be temp sensor. The revs are too high and out of range.

It is something do with air getting into the manifold Which could be sticking throttle, IACV or a leaky vaccum pipe or breather pipe.

As a test reset the stepper then let the idle settle. Remove the connector from the IACV and the idle shouldn't change. Now try and rev it, do the revs still stay high?
 

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Hoppaz said:
I will check this out over the next day or so. Has anyone else experienced high revs which won't go down when you blip the accelerator. They stick at 2500rpm. Throttle body ok, stepper is ok.

Could a faulty engine sensor do this???

Appreciate anyone's thoughts on this
Hi you may like to refer to a similar thread which i launched !. I have a similar problem. Basically my plastic throttle body is allowing some air to pass when its supposed to be closed. I have had it off and with a good level of light behind it,some gap is visible between the butterfly and the bore. To finalise the diagnosis i bolted it back on,disconnected the air intake to the stepper and plugged the breather which feeds from the air itake to the rocker ox. Now when i blocked off the air intake side of the throttle body with a hand which was wearinf a surgical glove (for good seal) revs normalised and all appeared fine. I'm on the hunt for a new body at present.
 

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Discussion Starter #10
ashy said:
Make sure that the vacuum pipe from the throttle body to the Charcoal cannister is properly connected and not leaking.
This can cause the revs to go a bit wild.
Pipe is connected fine and is not leaking.
 

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Discussion Starter #11
Right did some extensive testing over the weekend with someone else 214 which is the same year. We did some comparisons and swaped a few parts over to rule out problems.

Firstly it isn't any of the pipes stepper or throttle body. The other car seemed to have the exact same back pressure as my own accept this car knew how to deal with the pressure that is being pumped back into the plenum whereas mine doesn't.

My mate who is a good mechanic and myself have a good idea that it is the MAP sensor in the ECU.

Just recently on a long journey even when venting the rocker cover breather gas to air the car experienced the same symtoms as previous... first idles at 1500 rpm (so car pulls you along in gear without using throttle) then after the engine is warm the car idle sticks at 2500 rpm now and again (blipping throttle does nothing). It is totally iratic with the rocker cover breathing gas to air but does it consistently when all of the breather pipes are connected to the plenum (as they should be).

Does anyone have any ideas (or agrees or has had the same experience)??

Also is it possible to fit a new MAP sensor (or get one from a similar ECU in a scap yard) to my exisitng ECU? If so is it difficult? (my mechanic mate just happens to have a degree in electrical engineering).

Any thoughts or comments would be much appreciated.
 

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Faulty map means replacment ECU I'm afraid. Non servicable part. Be aware if you get a replacment you will need the alarm ECU and fobs with if not you will need the ECU matching to your current system.
 

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ashy said:
Faulty map means replacment ECU I'm afaria. Non servicable part. Be aware if you get a replacment you will need the alarm ECU and fobs with if not you will need the ECU matching to your current system.

There are those around these forums who can match you ecu and 5as Im sure its not too 'Lates':getcoat:
 

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Discussion Starter #14
Thanks for the info...

Before I start delving into replacing / repairing the ECU does or has anyone had similar problems???

Or doesn anyone else have any ideas to what the fault is??

I don't get any ECU warning lights but I am running out of ideas.
 

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Discussion Starter #16
ashy said:
It won't be temp sensor. The revs are too high and out of range.

It is something do with air getting into the manifold Which could be sticking throttle, IACV or a leaky vaccum pipe or breather pipe.

As a test reset the stepper then let the idle settle. Remove the connector from the IACV and the idle shouldn't change. Now try and rev it, do the revs still stay high?
Sorry to answer your question late but resetting stepper does nothing and neither does removing the connecter to it. Revs still stay high

Anyone got any suggestions?

Does anyone know where I can go to get a diagnositc done to see if there are any faults in Newcastle Upon Tyne area?
 

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Any ideas or suggestions anyone??
this is an old post so im not sure you will still have the problem, but try resetting the stepper motor

ignition off
wait 10 secs
ignition to no.2
wait 10 secs
push throttle to the floor 5 times(quick succession)
wait 10 secs
ignition off
wait 10 secs

start engine.....stepper motor reset :)
 

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mg_zr
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if there was a bolt jammed in the stepper pipe then the throttle might have been jacked open to maintain idle and the ecu now cant pull the revs down enough with the stepper now attached, just a guess. if you hook it up to a laptop you might see that the stepper is wound right in to minimum steps, dont know what that could be but maybe 1 to 10 steps. could be throttle switch or bad wiring maybe, done quite a bit of bad wiring on my 160 and a friends 25 recently. like ashy says try disconnecting and blocking off the evap pipe and the servo to eliminate leaks there, could be airleak elsewhere too.
my first point of call would be to fully close throttle screw till 'sticky' then open half to one turn until not sticky, reset stepper/throttle range with pedal then take it from there.

hth

jesus this posts older than my kids??????????????
 
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