reving issue need help

[gibbon1982]

Have an evo 4 and noticed that when the car is warm its sits at 900 rpm and drops to 850rpm and back to 900rpm. Some times when reversing then stoping the car drops to 300rpm and sometmes cuts out. Any ideas or is that normal and im being to anal???

 

[B6lee]

What dump valve do you have ?

 

[Jonny IX]

is the 4 ecu the same as the 9 for earning idle........

if it is then disconnect the battery for 20 mins then connect and start car...turn on all electrics A/C , wipers etc then let it run up for 20 mins or so and it should re-learn the idol

(thats how Ant told me to sort mine out...worked a treat )

but as Lee said could be a BOV issue ....

 

[GG205rob]

Yeah 4 ecu learns base idle in the same way

 

[gibbon1982]

hi thanks guys for the info.....this is my first evo and love them!!!

the guy who had it before me put a hks dump valve which in my mind is too bloody noisey!!

will try the ecu trick thanks

 

[Jonny IX]

hi thanks guys for the info.....this is my first evo and love them!!!

the guy who had it before me put a hks dump valve which in my mind is too bloody noisey!!

will try the ecu trick thanks

could be the dump valve if its the ssqv have you got the re-circ kit for it ?

I could be wrong but im sure i read somewhere that anything from 5 down struggles with idle issues with this BOV

 

[GG205rob]

could be the dump valve if its the ssqv have you got the re-circ kit for it ?

I could be wrong but im sure i read somewhere that anything from 5 down struggles with idle issues with this BOV

I've got an ssqv on my 4 and its fine. Very occasionally the revs get low when letting off after high revs. Never stalls and thats only very rare. Guess i could just be lucky though?

 

[sponners]

might need a base idle reset, if the battery hasn't been disconnected for some time and the car is used regulary then dont bother disconnecting to reset as it wont help.

 

[gibbon1982]

when its cold first thing its revs at 1500rpm.....then when you drive for 5 mins it sits at 1100rpm....only after a good drive it calms to 900 and then blips between 850-900. sounds like its missing i think.....ill try plugs...

also the typical loud lifter......have found a site which intructs how to clean lifters....was wondering if its just better to replace them with the 3mm upgrades??

 

[GG205rob]

First thing would be to try resetting base idle.

I know lots of people say that cleaning the lifters helped, i did mine and it made no difference. If you can afford it get 3mm ones to stop potentially having to do the job twice.

 

[B6lee]

its hit and miss with dump valves but its comon knoledge that evos dont like atmosfheric ones.

the effects are stalling when preforming manovers or stop start in traffic. what happens is cos when some people manover in such a manor as to generate a small amount of boost this would normally vent back through the recirc valve into the intake. as this doesent happen the intake tends to choke causing the stalling issuses your suffering with