my new ka is running really rough..

[thekage]

I bought a new 240sx las week. 121k on the KA. It idles really rough at around 500rpm.. kinda low. And every once in a while I have to pump the gas when cranking to get it to start. Planned for this weekend is an oil change and new spark plugs. Anything else off the bat I should think about with this engine? Clean this? Change that? kind of things?

[240sxHmooj]

I might be a tard but correct me, check your FPR. Since you doing a tune-up, might wanna replace your fuel filter with a z32 filter too.

[naed240sx]

Some of these might be unrelated, but you should pretty much get to work on replacing a bunch of minor things, since its an older car. Id say drain, flush radiator, new fuel filter, transmission oil change, diff oil change, seafoam car,o2 sensor, all that good stuff

[eds13]

you might want to check your timing. because you should be idiling somewhere between 700 and 800 .just my $.02

[lrb_2000]

you can always just unplug the tps sensor, and turn up the idle.... then check the timing when it's at 700rpm, or else it won't be accurate.

[tonynalli]

check to see if your idle air valve (i think thats what they call it) is pinched for some reason or make sure there is nothing pluggin it up. injector wires also, and mabey check your fuel pressure

[SOHCSE]

Not sure what year you have but if it has an AIV, clean or remove the sucker. I had the exact same issues with my pignose. (still have to pump the throttle to get it to start cold tho)

[thekage]

Ok so last night I changed plugs and wires. a couple plugs were kinda fouled up.. The car revs alot easier now! But the engine shakes.. and it idles smooth in park. But in drive or anyother gear it drops from 750 to 400-500 rpms and the shaking gets worse.

[SOHCSE]

Yeah, mine was like that. After a while I would have to put it in neutral when moving slowly or stopped to keep it from stalling. Since you didnt comment on the AIV I'll assume that yours is new enough not to have one.

[InsanityInc]

sounds like you may just have a transmission problem.

[thekage]

mine is a 91. so it has the aiv. I have to check that still. The transmission is going soon anyways so I hope that is it.. because I got 2 full 5 spd swaps laying around waiting to go in.

[NateDogg]

If you have to pump the gas to get the car to start, chances are you have a fuel injector leak. When you press the gas pedal down when cranking, more air is allowed into the engine and helps created a burn-able mixture, assuming you have too much fuel due to a leak.

You can tell which injector is leaking by looking at the spark plugs. The darkest ones (wet preferably) are the culprits.
Modified by NateDogg at 10:40 PM 8/28/2005

[thekage]

nate dog I think you are right. Apperantly overnight it has started missing really bad as well. I think ive got a bad injector or harness... I will let you all know what I find later today