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Rough Idle (Rover 214 16v MPI 1993)

7.7K views 26 replies 11 participants last post by  Dr Dave  
#1 ·
My rover has started playing up. The story goes. On start up in a morning all seems fine and sits happily at fast idle until reaching normal operating temp. When it falls to normal idle speed the car seems to shake and become very rough. Steering wheel vibrates, gear knob shakes, interior mirror vibrates. Upon my daily morning drive down the M1 2 junctions the idle seems to feel smoother but not as smooth as it shoud be. Mirror and steering wheel stop vibrating, but gear knob stiull shaking. There is still a vague feeling of roughness to the engine though. Whilst driving all seems ok, no power loss no stalling, do get a second of vibration through out the car about 3000 revs though. Tried changing the usual plugs, dizzy cap, rotor arm, leads, fuel filter, air filter and coolant temp sensor but to no avail.
Any advice please people??
 
#2 ·
Don't know if its the same on the 214 but on the 216 the warm idle speed is set independently of cold idle. Might be worth adjusting the base idle speed if poss - on my 216 you have to disconnect the wire from the IACV (can't remember what it stands for but know what it looks like!) and twiddle a screw until all is sorted. Then pull the hazard warning fuse for 10 secs to cancel the engine fault code, reinsert and you're fixed. But the 214 might be completely different...!
 
#5 ·
okay - teach me to stick to the cars I own! :doh:

A last bit of uninformed speculation on the 214 (my dad used to have one) - wasn't there some kind of sequence of stamping on the accelerator pedal x times, turning the key y times, and doing a little dance around the car (or something similar) that reset the MEMs and made it rethink its idle speed?
 
#8 ·
is it definitely to do with the idle speed?

when i had my nova (before i was got the rover) i had a problem sort of like this, and sometimes the car would just cut out completely when stood still, even if it was warm.

the problem was to do with the 'points' (i think, but not really sure) on the carburetta. all that needed doing was taking them out and blowing the dust out. my usual mechanic did it for me for free.

not sure whether you're experiencing the same but its worth finding out if it could be something this simple!

Paddy
 
#12 ·
Coil has been replaced.
Had a bit of success over the weekend. Had a look at the throttle body really closely and it seemed that one of the throttle return springs had come disconnected. Its the coiled spring on the throttle cable side of the housing, the one which returns the idle stop screw to the stepper motor pin. The throttle was only returning via the other spring behind the tps. Reconnected the spring and there seems to be a lot more resistance when opening the throttle by hand in the engine bay. After starting the car and doing the gas pedal "pump 5 times" trick there seems to be a definate inprovement but alas the idle is still not completely smooth, but is better. Could the stepper need adjustment via a t4? I'm assuming its the stepper at fault, or being out of adjustment as reconnecting the spring has such an improvement.
 
#18 ·
Re index the stepper to a "base" (sometimes called runline) position based upon the throw of the TPS. It basically calibrates the throttle shut position in the ecu, and indexes the stepper out to a "known" starting/idling position..

The ecu will then adapt the stepper offset to keep the idle within limits.

Brian.
 
#24 ·
Damper

Hi,

had this problem on our Vauxhall Omega. Maybe it's a similar case. Check the damper that controls the air intake. Maybe it's dusted or covered with dirt so it won't flip properly. In that case you should use some cleaning agent to remove that crap. A lot of VW's suffer from this, too. Under the influence of higher revs during warmup this will not occur. I suppose you notice the prob when the engine returns to usual idle revs.

Hope this may help.

Tom
 
#25 ·
I had a similar problem with my 214sli. I fixed the problem by cleaning the tube that goes from the throttle to the ECU, it's the absolute pressure sensor vacuum hose. Mine was blocked and effecting the idle revs and low revs when warm. The engine would cut-out, even when warm and the idle revs would jump about. After cleaning the tube, everthing ran smooth.
 
#26 ·
newblueturbo said:
okay - teach me to stick to the cars I own! :doh:

A last bit of uninformed speculation on the 214 (my dad used to have one) - wasn't there some kind of sequence of stamping on the accelerator pedal x times, turning the key y times, and doing a little dance around the car (or something similar) that reset the MEMs and made it rethink its idle speed?
Spot on, occasionally (usually approaching a service) my 214 starts over revving, idle oscilates around 2.5kRPM, I found that giving the engine a couple of bursts of full throttle into the red sorts it out temporarily (also scares the crap out of watching pedestrians).