Ni5mo180SX

Well ever since I took the manifold apart (87 GXL, removed air pump, 6 port system, rerouted TB coolant mod, removed 2nd set of TB butterflies ), im still in pursuit of trying to get everything up to optimum performance. Before the ports were removed, the car ran like crap. I had the 3800rpm stumble, no power, the exhaust manifold would get amazingly hot (the manifold and O2 sensor glowing orange on a normal night drive) etc. etc. After cleaning performance did improve and the stumble was gone but it didnt feel up to speed. I also changed out the plugs, wires, tranny fluid, engine oil, oil/air filter, cold start sensor, belts etc. The manifold never got that hot again after cleaning the ports. Well, after messing with the crank angle sensor, it made a HUGE difference at first. The car didnt wanna stop pulling. Like someone mentioned, it was like a two stroke engine hitting its sweet spot. The car revved hard and willingly deep into 7, very noticeable making big power gains which would progressively increase after 5krpm. I then played with the CAS myself and since then have lost some of that power seemingly. It usually idles at about 1700RPM, which sometimes randomly drops to 450-600. My tps is correctly adjusted(I think). I tried to adjust timing but the needles won't line up unless I retard timing all the way and the car is on the verge of stalling. The idle adjust screw makes no difference whatsoever. I saw a post mentioning clogged cats make your eyes burn (?) and this FC really does that to you lol. I figured I had a vacuum leak from the ACV area and orderred the K2RD block plate which I put in this morning but it didnt help. Ive looked around the engine and can't find anywhere it would be leaking from. Could it be that a vacuum leaks causing my problem? Or clogged cats? Clogged fuel filter? Timing set way off? I really have no idea anymore. Hopefully this made some kinda sense (its 230AM right now) and you guys might have some idea of what it might be. Or maybe its just me?? Maybe the lack of torque from removing the 6 port system is making me "think" theres less power when its just been shifted to the top end area? I don't think thats it though because I recognized when the car was running at its peak that "this" was the way it was supposed to be and ive noticed when its been lacking. Thanks in advance to everyone who took the time to read this. Hopefully I got everything covered. Thanks again.

Ni5mo180SX

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blu_gxl

possible intake leak, if you used sealant or new gaskets and are sure it's sealed the continue. my car would idle high when i had one have you checked the tention on the throttle cable?

how often does it drop to 400 and for how long?
have you tried to adjust your variable resistor?
and your bac?
also, did you mess with the idle stop? it's on the side not the same as the idle set.
what you should try is make your variable resistor full lean, turn your bac all the way down, and your idle set screw all the way down. then see if the car will start, just adjust the idle with your idle set screw alone. once you get that set, set your tps again when you set the tps hit the gas a couple of times just to get is in. then you should be able to pull the bac screw out slowly until it's back out all the way. reset w/ idle stop screwif it get's higher (it should). then gas it a couple of times and it should be fine if it still is high then you might want to look for vacume leaks. i'm sure someone else will have a better(easier) way to help you but this has worked for me.

james

Ni5mo180SX

I havent checked the tension on the cable yet actually. It drops in the 400 region once it seems to hit a certain temp. It only happens to me during the days after running it hard, never at night even though I run it harder, so I guess its related to some sensor being really screwed up. Idle stop? how do I adjust it or my variable resistors and BAC? Thanks for the help.

Ni5mo180SX

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Ni5mo180SX

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No7Yet

Problem is, you changed so many things at once, and you were in so many parts of the engine bay that it makes it impossible to make anything but sweeping guesses.

I'd start at the simplest point first - make sure that the TB's not binding up. If that's not it, start going through every possibility.

Sorry that I can't be of more help...

Brandon

Ni5mo180SX

Yea thats true. Its kinda hard to figure out what it is considering we went through almost every sensor/line that has to do with the idle. When you say make sure its not binding up, how do you mean? Thanks, every suggestion so far (2 lol) has been great and im probably gonna end up checking them out.

No7Yet

Make sure that the throttle plates are closing completely.

Also make sure that the BAC plunger isn't getting stuck open.

Brandon

Ni5mo180SX

I see. The BAC plunger? Would I see that taking the BAC unit off?

No7Yet

Yup. http://www.1300cc.com has a decent BAC cleaning writeup - I'd write it, but I'm being lazy today.

Brandon

Ni5mo180SX

oh, got it. I'll check it out.

Ni5mo180SX

wow its amazing how much you can see with the car out in the sun lol. I checked it out and noticed 4 lines that weren't connected to anything. Two were behind the TB towards the firewall. It was two tips plastic nozzles coming from the side of the TB. Anyone have an idea on what those are for?? The other one I found was below the BAC. And last was one near the bac that looked like it was coming otu of the tranny

Ni5mo180SX

BTW - there was slack on the throttle cable

Ni5mo180SX

ok this is getting pretty frustrating. The one under the BAC is supposed to be open. The two plastic nozzles did nothing for the idle when I covered them neither did the one by the tranny, WTF, where am I getting a leak?? Is my only choice pretty much to tear everything down again?

No7Yet

Probably. You've just got to be careful. Do you have an FSM? If not, download it from http://www.fc3s.org . It's big, but worth its weight in gold.

Oh, and I'm probably the wrong person to ask about anything stock, sorry Especially emissions-type stuff.

Brandon

Ni5mo180SX

Yea this is so gay. Im getting pretty pissed off with the car. Like I said in the other thread, no matter how much **** I fix something else keeps breaking. The car wont even hold its idle!! Thats so fu**ing annoying. Theres a noticeable loss in power and its running like crap with the exhaust falling apart. The horn honks by itself so id like to destroy the part causing it too.

No7Yet

Don't get discouraged. Make a list of things to fix. No particular order, but try to mix them up in terms of big and small. Download the FSM and make it a goal to fix one thing per day. Every night, come here and ask questions about tomorrow's fix if you aren't sure how to go about it. For "big" jobs (like diagnosing the idle), get some input and break the item into diagnostic "sections" (say, first checking for vac leaks, then making sure the throttle plates aren't sticky, etc).

It's simply the nature of these cars that there's always going to be something that needs to be fixed, but you can minimize the effect of these things by taking it one step at a time. It'll build character, too

Brandon

Ni5mo180SX

Well, like you said, most likely im gonna have to take the manifold apart to find the leak. I dont think it should be too difficult to do its just that I need to find time to do it with work and shitty summer school. Since I removed my old sleeves do you think id get any gains from going with the pineapple racing sleeves? Im gonna order the CS cat. back on monday too.