Evo 4 stepper motor

[Drew6969]

Hi people.

Just a quick one if i can. I've the common problem of my Evo 4 hunting up and down the revs and/or cutting out when coming to a standstill after driving on boost for the last 2months now. I've bought 3 different stepper motors, have reset the ecu and checked all vacuum hoses however the problem still remains. I took it to a specialist a few weeks ago who also advised that the stepped motor is the problem, i put the 3rd stepper motor in today however the problem still remains and i'm out of ideas, any suggestions would be a huge help as i'm off to Mallory park at the weekend and don't really fancy the 160mile drive with the car cutting out at every single junction or traffic light :cry: Thanks in advance

 

[Gareth Baldwin]

Try resetting the throttle position sensor, its located behind the inlet manifold. with the ignition on fully unplug the connector for 10 seconds, then plug it back on for 10 seconds, then pull the trottle cable to full throttle for 10 seconds. then start the car.......problem fixed? let me know. you might need a new sensor if it happens again but you can keep resetting it for the time being.

hope this helps

 

[Steve220]

Have you got an atmospheric dump valve?

 

[jay2k6]

Just jumping in I've got the same prob lol only started two days ago already doin me swede in. Mines a bit different Ive reset and it's fine on tick over but soon as I've gone for a spin, the revs takes ages to come back down usually sits around 1800 or 2000 in till you turn off or wait a life time, quite really was sitting at lights next door to a copper, was getting really dirty looks rofl

Going to clean the idle, egr valve and check ohms of the valve, but any other ideas would be happy to receive

Sorry drew6969 for jumping on ya thread

 

[Drew6969]

Hi Gareth, i tried your suggestion however the problem is still present i'm afraid mate but thanks for the advice. Might just bite the bullet and leave it to the specialists

 

[Drew6969]

I don't have an atmospheric dump valve Steve although i've read few posts which say that this could be the problem, apart from the filter its pretty much standard

 

[micevo]

have you tried cleaning the throttle body? also try your tps is running the right voltage sure it should be 0.71, cant remember which wire you put the probe on but do a search that should tell you....

 

[Drew6969]

Hi Jay2K6, i've also had the same problem (very high idle) with the second stepper motor i put in, it would idle high from cold and when warmed up it would hunt between 200-400RPM before cutting out. At other times it would hunt between 1500-2000 when warm which you will agree makes you look like a prised p***k at the reds

 

[jay2k6]

Hi Jay2K6, i've also had the same problem (very high idle) with the second stepper motor i put in, it would idle high from cold and when warmed up it would hunt between 200-400RPM before cutting out. At other times it would hunt between 1500-2000 when warm which you will agree makes you look like a prised p***k at the reds

Oh yes have to agree there, well I cleaned my idle with carb cleaner, and so far so good, she's gone back to normal, but that's only today so hopefully she'll stay there, but if not I'll be taking the idle out again and testing it with the multimeter to see if the ohms are right, also I'll strip the egr down and clean that with the carb cleaner, but it's the ohm test that will give me the ans I require me thinks, will keep you posted mate

 

[leo]

Hi Jay2K6, i've also had the same problem (very high idle) with the second stepper motor i put in, it would idle high from cold and when warmed up it would hunt between 200-400RPM before cutting out. At other times it would hunt between 1500-2000 when warm which you will agree makes you look like a prised p***k at the reds

hi try the ecu temp senser as that will act as choke on cold and it will give you high revs wen hot

 

[evo arm's m7960]

as above but only use a , OE ,part as i changed mine for a cheap one and it made the car worst :O(

 

[Drew6969]

MICEVO, i've cleaned the throttle body about a month back however i will do a search and see what the meter comes up with, willing to try anything

leo, i will do a search regarding ecu temperature sensor and keep you posted

 

[jay2k6]

Alright mate you had any joy yet? i'm back to looking like a fool at the lights again, lasted a couple of days and doing it again, ive just installed a second idle control valve off a working iv, yes youve got it still playing up lol but ive noticed that when i reseted the ecu, she was ok but when i turned all electrics off she went up instead off down, so going to reset ecu then let idle at normal see if that helps

 

[Drew6969]

Hi mate, i've not had a look yet as the car broke down last week, what i thought was a nackerd fuel pump turned out to be the chopper plate slicing the balance belt, crank angle sensor and timing belt to the point of avoiding a new engine by a knife edge but all sorted and got the car back today. I am going to try all of the above hopefully over the weekend and i will let you know how i get on, good fun these cars haha