From what i have heard it could be either the coolant temperature sensor or if there is a loss of power then maybe the lambda sensor, other than that i would say get a diagnostic on it

 

Diagnostic says nothing, any other ideas??

 

Are the two leads that feed the VVC solenoids fitted the wrong way around? This can cause rough running.

Also, could be the coil packs deteriorating.

Are you sure there's no diagnostic info? I took my 25 gti to a Rover dealer, to be told there were no error codes logged, then took it to someone who could read and write, and they found a bunch of error codes logged. But the MEMS diagnostics system is not infallible, it can indicate no fault faound when the engine isn't running right.

Keep smiling,
Mark

 

oh please help

someone on here wrote about having the same problem and it logging the same codes as me but they have sod all to do with it, p1520 and p1522 they arent anything to do with it, they arent even registered to mg!! just my luck, any one please advise!!! x x x

 

go for the obvious first m8 new plugs & air filter, fuel filter.

coil packs are a bit dearer lol so fix consumables first

try disconnecting the earth lead ( - ) on the battery for 20 mins - see how it runs when you put it back.
lumpiness on mine at idle was dirty air filter, but it wasn't so bad that i had to rev it hard to clear - sounds more like a fuel fault to me tbh.

have you got a low cold air feed on it & gone through any big puddles?

*also had a misfire caused by loose connector on the stepper motor ..........

 

p1522 is a vvc/actuation fault code.
p1520 - jury still out on this code as far as I'm concerned.

 

According to my information, P1520 is Camshaft position (CMP) actuator control, engine oil temperature sensor - circuit malfunction.

Probable causes are listed as "wiring, engine oil temperature sensor, ECU"


Hope this helps

 

found a new code for this problem

p0300 is the code now registering !! any help appreciated x x

 

p0300 is the code now registering !! any help appreciated x x

The misfire across all cylinders code iirc.......

Okay, what I would suggest to everyone who is suffering these symptoms;

Lousy starting from cold,
Lumpy idleing,
Lack of power in lower gears,

Get your car on a LIVE data diagnostic. The areas you want to pay particular attention to are the STFT (short term fuel trim) and LTFT (long term fuel trim) readings. Look below at this guide from previous findings.

If you have a scan tool, look at the Short Term Fuel Trim (STFT) and Long Term Fuel Trim (LTFT) values. Normal range is plus or minus 8. If the numbers are +10 or higher for STFT and LTFT, the engine is running LEAN. If you rev the engine to 1500 to 2000 rpm and hold it for a minute or so, and the STFT value drops back down to a more normal reading, it confirms the engine has a vacuum leak at idle. If the STFT value does not change much, the lean fuel condition is more likely a fuel delivery problem (weak fuel pump, restricted fuel filter, dirty fuel injectors or a leaky fuel pressure regulator) than a vacuum leak.

If you are suffering from the above symptoms, the chances are you are suffering from a vaccum leak or a fuel delivery issue.

So, first port of call would be to try and clean out the injectors using a fuel additive like wynns or redex etc. Give the car an italian tune up, long stretch of road, 3rd gear, boot it for a mile or so, I stick it at 50-60 but some go higher (dont redline it).

Next it'd be change of fuel filter and possibly fuel pump. Then after all of those, if the problem is still there, change the manifold itself.

 

if its misfiring badly, leave it running on drive (preferably running badly!), then check all plugs, if a pair is fouled it will give you an idea.....
check plugs, leads, coils and check coil/injector wiring harness and plug (under throttle body). then on to air leaks, fuel, compression test.
bad sensor or blocked cat.
P1520 will still be there, is P1522 clearing/returning?

 

all that came up on this test was p0300 its this bloody misfiring and idling wrong, the pull off is naff and is now happening in other gears not just 1st and 2nd, its driving me crazy, i changed the sparkies and it didnt make any difference......any other ideas?

 

as above! my money is on a bad coil or a bad coil/injector wiring harness. Any other codes?

 

No none just that one, oh i wish i could sort this bloody thing. aaarrrrhhhhh!!!

 

still have this problem.... anyone come up with a solution????

 

i still have same prob with mine.

does the car ever cut out or just drop low as if your going slow in a low gear?

do you get power at all evan at certain poisitions on the revs?

looks like it could be the same as mine as setting of is rate bad! i can't evan wheel spin it, which should be no problem for the 1.4 16v

 

I've just had mine repaired. Had the same problem as you as it got cold though it got worse. Neutral would misfire sometimes to begin with, then more over time, and no power throughout gears not to mention the awful sound from the engine (like a bag of spanners). I changed the coil pack (no2 was faulty) but this only bought on the ECU so i changed HT leads and job done.

When it began it was only misfiring once every so often, but once the coil really begins to break down you should be seeing a drastic change in no time (mine was around a week for it to finally die and lose real power by the day). If this happened its probably the fault.

Sometimes diagnostic doesnt pick it up i dont know why, probably depends if the equipment is suitable as rovers are quite funny cars.

 

My car was a rover 25 1.4 16V 2001 (newer system ht etc) Really does sound like your coil if diagnostic didnt pik it up being KPS its unlikely to b fuel injection as you were saying it began inconsistent. Id put money on Coils or HT's

 

The misfire across all cylinders code iirc.......

Okay, what I would suggest to everyone who is suffering these symptoms;

Lousy starting from cold,
Lumpy idleing,
Lack of power in lower gears,

Get your car on a LIVE data diagnostic. The areas you want to pay particular attention to are the STFT (short term fuel trim) and LTFT (long term fuel trim) readings. Look below at this guide from previous findings.

If you have a scan tool, look at the Short Term Fuel Trim (STFT) and Long Term Fuel Trim (LTFT) values. Normal range is plus or minus 8. If the numbers are +10 or higher for STFT and LTFT, the engine is running LEAN. If you rev the engine to 1500 to 2000 rpm and hold it for a minute or so, and the STFT value drops back down to a more normal reading, it confirms the engine has a vacuum leak at idle. If the STFT value does not change much, the lean fuel condition is more likely a fuel delivery problem (weak fuel pump, restricted fuel filter, dirty fuel injectors or a leaky fuel pressure regulator) than a vacuum leak.

If you are suffering from the above symptoms, the chances are you are suffering from a vaccum leak or a fuel delivery issue.

So, first port of call would be to try and clean out the injectors using a fuel additive like wynns or redex etc. Give the car an italian tune up, long stretch of road, 3rd gear, boot it for a mile or so, I stick it at 50-60 but some go higher (dont redline it).

Next it'd be change of fuel filter and possibly fuel pump. Then after all of those, if the problem is still there, change the manifold itself.

I have asked this question earlier but no reply, whats the best kit to get to do a full 'LIVE data diagnostic???

 

Fixed!!!!!!!!!!


Woooooooo hooooooooooo

 

so what was it?

 

so what was it? it would be nice if you told us.for future ref and all

 

I just plugged mine into elm and checked the STFT and LTFT when revving at 1500.

Do you have to wait until the car is fully warmed up? I ask this because the STFT was reading between -13% and -29% after about 5 min of running.

I believe my car is running lean and is having problems in closed loop.

Also, where can I find a list of the parameters that all the sensors should be working and at what rev's etc.

Thanks

 

Could you tell us what was the problem?

 

Clogged air filter? :dddc:

 

if all else fails, do a throttle re set proceedure.

 

my car is doing exact same, idle all over place then juddering when i accerlerate. done plugs,cleaned fuel filter,throttle body still juddering. What fixed your car m8?

 

i think it was the throttle thing sensor top of air intake pipe, black plastic top with white underneath. was sending a bad reading thats on my car anyway.
the name is throttle potentimeter sensor. Apparentl;y it wasnt sending the right signal when i put foot down. Its on the 160vvc. for futre ref to anyone.