Question #1 of many lol..

[SpoolingNation818]

I am new to Nico and i recently bought a 90 240sx. the car has a twin cam ka24de and when driving the motor tends to have a repetative tick coming from the top end. this only happens when driving the car. at idle it does not tick. i've been researching it and came up with a few things that could be wrong... Valve seals are bad, timing chain guide or possibly a bad lifter? the tick doesn't change tone at all it's just a constant tick tick tick. im just curious if anyone else has had this problem before also

another thing is my idle is very rough. when i start the car it revs up a little past 2k then slowly comes down to around 1400-1500 and after a few minutes it reaches 1100. sometimes it acts like it wants to die and bounces from 500 to 1000, it has actually died a few times from this. when driving the car and coming to a stop i push the clutch in and the idle almost goes all the way back to 2.2k or so then when fully stopped it crawls back down to around 1k. could it be my tps? these may not sound like newbie questions lol. but i've been researching this on the website for a few days trying to find a thread where someones had these problems. im not having to much luck. any information is very much appreciated. thanks

[simmode1]

The ticking noise sounds like the typical 'vavle tick', it's the sound of your lifters not getting enough oil flow. Alot of KA's have this. It's not good, but it's not the end of th world.

The rough idle could be alot of things: dirty maf, vacuum leaks, needs a tune up, etc...

[Two Fowty]

i kinda had the same idle problem (and still do). i adjusted the tps a bit and then my idle stayed around 500-800, but still fluctuated and caused my car to shake annoyingly. I recently ran some fuel injector cleaner in my car and now my idle doesnt fluctuate like it did.

But when I rev, my rpms wil drop down to 1100, and then sit there a few seconds, then slowly and gradually drop to normal idle rpms.

so i say, fuel injector cleaner cant hurt.. try it out

[Uberck]

+1 valve tick. my ka had the same top end tapping noise before it blew and it was a worn valve seat. the vacuum leak def check all lines especially brake booster check valve. good luck

[Gabes13]

needs a tune up

yeah broski!

then check all your air sensors (maf, tps air temp blahblah) then your fuel (pump, pressure, injectors blahblahblah)

[Ajax]

90 240 had single cam. recheck your year.idle problems are notorious for ka engines. TPS, IAC valve, vaccuum leaks. Give it a thorough cleaning and inspection.

[Warped161]

90 240 had single cam. recheck your year.idle problems are notorious for ka engines. TPS, IAC valve, vaccuum leaks. Give it a thorough cleaning and inspection.

if the motor was swapped to dual cam then the idle problems could be a result of wire harness issues or a poor swap.

[simmode1]

if the motor was swapped to dual cam then the idle problems could be a result of wire harness issues or a poor swap.

Oooooh... good point...

[Dill_XD]

Might want to check your ground wire too.

[SpoolingNation818]

good point good point, the motor was swapped from sohc to sr a few years back and before my friend sold it to me he took his sr out and replaced it with this dohc ka. right now i'd just like to get this motor running a little bit better because it's pretty rough lol and it doesn't help to have poly motor mounts.... which definately need to be replaced for now.. the dohc ka used to have a garret gt2871 on it, so my guess is that it's just a pretty banged up KA that when rebuilt for the turbo setup it was rebuilt very poorly.. i guess it's just a good excuse for me to go SR right away.

thanks for all the tips fellas im gonna look into all that was said and hopefully get it running a little smoother while i save up for my SR

[SpoolingNation818]

i went ahead and checked a few ground wires, both Fuse box grounds weren't ground nearly at all. i took off the bolts and it was like someone painted the engine bay and forgot to sand off where the ground bolts went and just took a screw driver and scratched away a little bit of paint. so i went ahead and sanded it down to bare metal and put them back on, started the car and it might sound od but just doing that i could tell somewhat of a difference, my idle wasn't nearly as rough. my knowledge isn't to well right now with motors but could those grounds have that big of an impact on the cars performance? i took the car around the block and through some fuel injector cleaner in it also. the cars idling at 1k with little to no Fluctuating. every minute or so it will drop down to 900 and then rise back to 1k and stay steady. is 1k alright? or is there a way i can adjust my idle to a steady 800 or so?

thank you for the help, very much appreciated guys

[i240sx]

THANK YOU FOR YOUR GOOD THREAD, WE HAVE BEEN HAVING FAIL THREAD LATELY THIS WEEK...+1 FOR YOU...YES GROUND IS LIKE THE VEIN IN A HEART.. AND AGAIN 1990 ONLY COME IN SOHC, LOOK LIKE YOU GOT A DUAL SWAP..

[Dill_XD]

YAY i was right!