89 s13 w/ s13 sr20 redtop wont idle!!

[240bryce]

Alright so i ordered a new (used) sohc maf and just put it on like 30 mins ago.. doesnt work. still has the same idle problem!
Iv gotta get this thing runnin and driving! any advice guys?
Its so frustrating!!

[PyR0NiAk]

Sadly this car sounds like mine... Check your compression. Mine had 80% compression loss on cyl 3...

[240bryce]

Oh no.. okay thanks for the help man! i'll let ya know what i get.

[kamilp1908]

Lately I have bought genuine RedTop MAF (52F00) and all my problems with idle have been solved.

[PyR0NiAk]

The KA-E maf will work just as well as the SR MAF at low rpms. The KA-E maf doesn't become a problem until you start trying to rev it out... This, obviously, is not the case here.

[240bryce]

could it be a huge boost leak or something?

[skyline084]

na, as long as there's no massive leaks before you throttle body it would still idle.
Do you have the service manual for the motor? and a multi meter?

[240bryce]

Alright, i do not have the service manual for the motor.. but i do have a multimeter.

[skyline084]

the FSM can be found on this site.. search "Sr20 redtop FSM nico" and I'm sure it will come up with it. Find the wiring diagram, and become very familiar with it. Once you learn where all the wires go, check em all. power, signals, grounds. The manual shows you how to test pretty much everything.
Once you figure the wires are good and get power where they are suppose to, start testing all your sensors

[240bryce]

Awesome! thanks for the help man.
I cant seem to find the FSM though. Can you give me a link?

[skyline084]

Np dude

http://www.240edge.com/manuals/s14-sr20det.html

While looking for it, I've heard there's no FSM in English for the s13 redtop sr20
It's for the s14, but still the same motor as yours though.
If you get stuck or need help.. post a question

[240bryce]

Okay so one of my buddies came over yesterday and we got all the vac lines right, re-adjusted the TPS, and messed around with the CAS a little.. and we FINALLY got it to idle!! ... but only when the engines hot.. lol
I tried starting it up this morning, and it just did the same thing as always.. but after i got the engine hot, it idled kinda rough, but still.. i could step away from the car and come back a couple minutes later and it would still be running. lol
so with that recent change in the idle, i was wondering if it changed anything in the way that it drove. So i hopped in it and tried to back it outta the driveway, but as soon as i would start letting off the clutch, the car just wouldnt have any power, and it would die.
If you guys are confused i can always post a video, cause i know its a lot easier to see whats happening in a video rather than me trying to explain it.

oh and also we figured out that the battery terminals are gonna need to be replaced, along with the 4th cylinder injector pigtail (broken clip), and the BOV isnt working.. at all.

[skyline084]

So what change was made to make it actually idle?
All you gotta do is adjust one of your sensors.. your motor runs so you're getting fuel and spark.. just not at the right time.
If it was my motor, I would first test all the sensors to make sure they are working properly. If everything is fine there, than do the timing adjustments you need to make on CAS, TPS..and I think you said your timing was good, right? As long as it's close enough to at least get it running. A how to on most adjustments can be found in the service manual. If not, Google search or ask.

[skyline084]

any luck with the car yet ?

[240bryce]

Nah man. well i have it idling.. but still, only when its pretty warm. And when it does idle, its REALLY rough. heres what iv done to the car...
set the timing, tps, CAS, checked the ecu, 02 sensor, maf, coils, injectors, fuel pressure, spark, vac lines, changed the coolant temp sensor, spark plugs, the iacv is getting continuity.. but i dont know if its operating. it seems like iv checked EVERYTHING lol im stumped guys.
i have no idea what to do anymore!
Well heres what happens when i take it out for a drive...
When im revving it, it revs fine but you can hear some hesitation. when im backing it outta the driveway, it has some serious power..lol. when i kick it in first and start going, its fine, but then when it starts boosting, thats where the problem hits. It almost feels like its hitting a brick wall! when its under load, it bogs down HORRIBLY and backfires and starts bucking. Its so bad, im lucky to get the car up to 30 mph. lol
But i have no idea what it could be. Got any advice??

[skyline084]

Damn man, so you're wiring is all good. All your sensors were sending out the appropriate voltage on both +, and signal wires?
didn't you say your bov doesn't work?
My car would stall whenever the car was under load, and couldn't even make it to boost when my BOV wasn't working..
I wish I had an SR and lived nearby, I'd just swap out every part till we got the thing running lol
I'll keep thinking about what to check when I go to work

[240bryce]

Thanks for all the help man!
Is there anyone here who lives in ATL that would be willing to swap some parts from their car into mine so i wont have to buy parts??
Thanks!!

[bossgt]

What 240bryce meant to say is.......

Is there anyone in the north ATL area that can do us a HUGE favor and ride out and allow us to try his harness and ecu on your car with the same s13 sr20 motor in it? I am his mechanic buddy and we have literally tested everything......the only two unknowns to me are his wiring harness and the cam angle sensor.....if we could just plug in our wiring and ecu into a good running car, and it works, we can confirm that thos items are good, i actually was able to test the ecu only on another running car and was able to confirm it is good.

I just dont know if his harness is good, i think it is, i just need to be aure before i can rule it out. then lastly, if we had another cam angle sensor we could test then we would know that for sure....unless someone knows where we can get one locally for not too expensive.....

You know how it is guys, budget is tight and we dont want to waste a bunch of $$$$ and throw parts at the car.....

if someone is willing to ride out we will of course pay for fuel expense and buy you dinner or whatever you prefer for being so kind. We are just looking for another enthusiast in the area who is willing to help......me maybe even just getting a LOOK at someones harness will help me out.

Anyone who can help, let us know or call me!! 678-362-5685

Thanks all!

Peter

[skyline084]

Damn guys.. the wire harness and CAS are easy to check.

Wire harness:
If you don't feel like tearing apart the tape to check every individual wire, than check continuity from before ECU, to connector. That ensures wire is still intact.
Afterwards, apply voltage, check the FSM, and check each sensor to make sure it puts out the appropriate voltage. Same with the sensor wires on each sensor.

Actually dude, pull your entire harness out and check every wire. It will show you how simple a wire harness is, and that will also let you know there are no wires that have melted to one another.

Oh and your CAS is pretty much ignition timing control. It controls when your fuel injectors are going off. You have to test it two ways. One is the voltage wire, and 2 signal wires. If those are both good, take the CAS out and turn by hand to see if your injectors click.(I've never done this because I don't want to screw the timing up.. If my spark plugs are wet with fuel, than I know they're at least working is what I go by)

[bossgt]

Damn guys.. the wire harness and CAS are easy to check.

Wire harness:
If you don't feel like tearing apart the tape to check every individual wire, than check continuity from before ECU, to connector. That ensures wire is still intact.
Afterwards, apply voltage, check the FSM, and check each sensor to make sure it puts out the appropriate voltage. Same with the sensor wires on each sensor.

Actually dude, pull your entire harness out and check every wire. It will show you how simple a wire harness is, and that will also let you know there are no wires that have melted to one another.

Oh and your CAS is pretty much ignition timing control. It controls when your fuel injectors are going off. You have to test it two ways. One is the voltage wire, and 2 signal wires. If those are both good, take the CAS out and turn by hand to see if your injectors click.(I've never done this because I don't want to screw the timing up.. If my spark plugs are wet with fuel, than I know they're at least working is what I go by)

\

Already checked the harness via the pinout.....i am just not sure about the way the wires should be pinned out on the brown and grap plug that go to the body.....

And from what i have heard, it is possible for the car to still run with a bad CAS, so i was hoping we could try someones to see if ours is good or not....i would buy one if someone had a good one locally....just looking to see if anyone local would be willing to help out a fellow 240SXer!!!

[spikey_mikey]

sorry for bump but did you ever find out what was wrong? this is my exact problem

[skyline084]

damn forgot bout this post. Hey 240bryce you get yours up and running yet?
Spikey Mikey- will the motor even turn over?

[240bryce]

Well I kind if got it running.. In a way lol
It idles fine but rough only when it's warm. But it drives now but the only problem is that when you floor it.. It starts bogging & backfiring like crazy. I have no clue what it could be!! But it drives great & pulls hard in every gear at about half throttle.... Lol
HELP!!!

[skyline084]

lol damn man, you're having more problems than I am!
My RB is doing the same thing, backfires and and cuts out at WOT.
After tearing everything apart, found out it was a stupid injector not giving me fuel.

Check all cylinders are firing, and color of the plug. Ensure you have solid spark, and fuel.

[240bryce]

all cylinders are firing, color of the plug is fine, my injectors are good. i have no idea what else to look for man.
Got any ideas??

[S-ICHISAN]

i posted on the first page way back
i read u checked for continuity to iacv
but u need to check for 12v
i had the same issue when i rubbed harness...
put iacv to 12v
its blk/yellow
and my sr20det idles perfect

[240bryce]

thanks for all the help guys!!
But yeah i went out & checked the iacv again and its already got the black/yellow wire goin to it.
But iv got another question.. the body is an 89 hatchback & the stock fuelpump for the ka24e is still in there.. could that be my problem???

[PyR0NiAk]

thanks for all the help guys!!
But yeah i went out & checked the iacv again and its already got the black/yellow wire goin to it.
But iv got another question.. the body is an 89 hatchback & the stock fuelpump for the ka24e is still in there.. could that be my problem???

YES. There's a reason most swaps are done with the walbro 255s, and you found it. You're most likely running out of fuel at WOT.

[240bryce]

thanks for all the help guys!!
But yeah i went out & checked the iacv again and its already got the black/yellow wire goin to it.
But iv got another question.. the body is an 89 hatchback & the stock fuelpump for the ka24e is still in there.. could that be my problem???

YES. There's a reason most swaps are done with the walbro 255s, and you found it. You're most likely running out of fuel at WOT.

Wow... i feel like such an idiot haha thanks for the help PyR0NiAk. im ordering my walbro 255 right now & ill let you guys know if that was it!

[PyR0NiAk]

Wow... i feel like such an idiot haha thanks for the help PyR0NiAk. im ordering my walbro 255 right now & ill let you guys know if that was it!

No problem. Let us know if it fixes it or not. If not, I'll do some back tracking in your thread and see if anything else catches my attention.