Redlining

My 91 doesnt redline. When I step on it it goes up to 4000 then down to 3000 and just stays between. Changed: oxygen sensor, spark plugs (ngk) oil filter, oil, fuel filter, and air filter. Have any of you ever came across this problem?

is it a/t or m/t?

Manual

wow ive never heard of that. I mean if it can hit 4g then it should be able to go to redline. Could be your injectors but not sure.

I thought it was the injectors too, so I ran synthetic fuel injector cleaner in my fuel and I still got the same problem. My injectores are all working cause they're clicking the same speed. If I dont get any suggestions I probably will end up taking the injectors out and having the shop clean each one up. I need more info

mite wanna make sure the distributor is firing right. it could be that its ok for low revs because the timing is roughly ok, but theres a problem at high revs caus ur just a few degrees off or something?

My firing order is fine, but probably I am a few degrees off. It's not timed. Do I disconnect any sensors before I mess with the distributer?

www.240sx.org faq will help you.

changing your timing isnt hard but the way i did it i used a special tool thats like a light devise. you dont have to take off any sensors. there is a bolt that is in a slot around the distributor. Once you lossen that you can turn the assembly then you tighten it and check. If you dont have that tool then you might need to get it done by a mechanic. Hope i helped.

i experience that same thing with my car too! is it a ka24e or de? well i got the ka24e i could never get passed like 4000rpm on 4th gear it would probably go up to like 3900 or something like that i haven't figured out wha it was but yeah i used a timing light on my car and its perfect and i still get the prob.. i jus say F it i'm savin to do a sr swap anyways no need to fix the ka for now.. but yeah i was told it could be my injectors but i used an injector cleaner too and still nottin happened.. if u ever find out wut it is share the info and tell me too

Yeah my ka24de is still doing that shit. I had a friend come over and he said could hear a vaccum leak behind the intake manifold. He was going to spray the last of my starter fluid (cause it wont will not ever start without it) so I said hell nah. He's comming tomorrow with a stethescope and a timing light. It seems like whenever I hear 240 i hear sr20 comming just seconds later. HUH, WHAT ABOUT YOU!

Is there any vaccum diagrams for my engine on the net?

mine only revs to like 5k and like shuts down til i hit the clutch again and starts up again im gonna swap ecu's with a friend and see if that fixes it. i can see why your does that in fourth gear its called a speed limiter

It's not just my fourth gear it's all of them

Take off your distributor cap and make sure it is ok and clean the mafs with rubbing alcohol and a q tip.

yeah its on all my gears i can get up to 6gs on 1st and 2nd i think but on 3rd i get like 3500rpm, 4th i get like 4000rpm and 5th i only get like 4200rpm

I took off my MAF sensor to see if it was getting any power. I ran a continuity test (light probe neddle thingy) on the 3 wires running to the sensor and I noticed that the light would only come on when I attached the postive light probe to the positive on the battery and the negative to the black wire going to the MAF. The other two wires which I assume are the positives didn't turn on, so I'm gonna see if there is a break in between the sensor and the ecu.

Isn't the vacum diagram under the hood fo the car? I also had this problem (before my engine was messed up) I don't remember the specifics, but I remember not being able to rev past 5k in gear.

it could be either your ignition, or maybe your clutch is slipping?

I had a friend who's 84 z did the same thing they tried everything I think they finally fixed it with a new computer think under a hundred stock junkyard or $300 perf replacement. But then again something about a wiring harness rings a bell...

a slipping clutch overrevs and in a hurry courtesy my experience with my old escort beater haha, but at least it wasn't a civic

yeah, i agree w/ swimtx, a friend has 240 that had slipping clutch. barely made it out of a parking in reverse. the revs slowly went up and never passed 3 or 4k

If you can't get past 4000 or so in any gear without hitting the rev limiter, there are only 3 problems that it can be. Iv'e been through hell and back trying to fix that on my 89' single cam. I finally just got a Factory Service Manual and found out that the ECU is going into "safe mode." It said that when the MAF, Coolant Temp Sensor, or ECU malfunctions, it will go into safe mode and won't let you rev past 4000 or so. You should service your AIV and EGR if you have a rough idle. Good luck.

Now at idle when i give it gas it it just wants to die. It idles at 750.

I vote MAFS. My car would idle but when I tried to give it gas, it "just wants to die,". Try cleaning the prongs on it or get a new one. I warn you that these are expensive units. The cheapest one I could find was $265 at Autozone. Good luck