Knock sensor/timing

[armysweitzer]

Hey guys, recently picked up a 89 RB20 powered hatch. Well after several hours of looking it over ive come to realize 2 things.

1: my timing is advanced @ 40 degrees. If i set it correctly the motor doesnt run right, it feels like i have all turbo with no motor power at all its weird. 2: my friends think its the knock sensor(s). I just found a fsm on the r32 but it doesnt seem to have a wiring diagram.

I was wondering what you guys thought about the problem. With the timing advanced the car runs right but obviously is not happy (too much fuel+ lack of correct power) Any help is greatly appreciated on the matter

PS I also have an RB gauge cluster and everything works minus the tach and speedo, i was wondering if you had any diagrams of that or what you may think is wrong, i havnt looked too much yet. (jumps in flame suit)

Its an honor to be aboard the skyline powered crew and look forward to much learning...

Thanks a lot, Johann!

[WDRacing]

Wow, thats the most confusing thing I"ve ever read...

What motor is in the car?What is it like at Idle? What does it do at avrious RPMs?Does the motor have stock cams?Are they off a tooth?How do you know how much fuel your getting?

WD

[goofynick6]

Try switching around the clamp for the timing gun, the way the current feeds thru the wire affects the way the gun reads..

[armysweitzer]

ok sorry it was random, I know the timing is off 40 degrees, checked it with 2 guns. When the timing is correct it feels like im getting no power from the engine for what reason im not sure. When its advanced 40 degrees it feels fine. Im pretty sure the knock sensor is playing a roll in it.

Does anybody have the wiring diagrams ? Let me know thanks

1-RB20DET2-we have turned down the idle screw but its still around 1100 with the messed up timing3-car seems fine with timing advanced, with it correctly set it shakes/stutters4-yes5-no6-i shouldnt say getting too much fuel, not using it correctly due to timing problems...

thanks a lot guys

[eh?]

Redo your timing. When checking timing at the back loop it can read 2x the normal with different types of Timing lights. When you show 40 btdc it's really 20.

What you should do is removed #1 coil, and attach an old spark plug lead to it and plug. Check timing from there.

[BoostFab]

2-we have turned down the idle screw but its still around 1100 with the messed up timing

did you unplug the brown plug before adjust the screw?

[Carl H]

40 degrees eh?thats damn near impossible unless the cas is mounted upside down or something.it is possible tho that the driving dog in the exh cam is broken and when the cas was reinserted it was moved over a few notches.just a thought.

[eh?]

His timing gun is reading wrong. Common problem with RB's.

[Carl H]

His timing gun is reading wrong. Common problem with RB's.

i dunno man ive never had that problem with my engine and ive used quite a few diffrent guns on it.goofynick may be on to something as some guns the pickup is directional, so perhaps he has it wrong.

[Wulfgang]

Consider what is more likely:

1. He read the timing wrong. It's really at 20º, not 40º, so that when he sets it to what he thinks is 20º, it's really at 0º. That would make it feel very slow (like he said).

or

2. It was really at 40º and he set it to 20º. Somehow it runs really well at 40º of timing, which would blow holes through the pistons of most turbo engines (at least those built on Earth). But when he sets it to 20º, where it should be, some phantom problem with the knock sensor causes it to lose power.

Ok, so Johann, I seriously doubt you were running around with 40º (at idle!!!). Also, setting the timing incorrectly will not give you too much fuel. Find out how to do the timing correctly. It is pretty tricky on an RB.

Also, if you have a gauge cluster and the tach and speedo don't work, doesn't that mean that pretty much nothing is working? Or do you mean that you can tell when you are about to overheat or run out of gas, and that's pretty much everything you need to know while you're cruising along on the interstate at a speed you don't know and with the revs somewhere between zero and a gazillion? Just kidding. The tach fix is easy (search) and the speedo uses a speedo cable (which the previous owner must not have installed).

[WDRacing]

Setting the timing on the RB is simple....I mean, it's somthing my sister could do.

Pull off the timing gear cover, pull off the CAS (cam alignment sensor), pull off the CAS mount. Set the crank pulley to TDC (top dead center) This should be the mark that has an orange tint to it, the others should be white IIRC. (NOTE) It may take two rotations of the crank pulley to get the timing mark aligned at the same time the cam gear alignment marks are lined up. The two timing gears each have one indentation marking on a single tooth. This maybe a tad hard to see, but it's there. Once you find it, put a mark on that tooth with a paint pen for later use. When the crank is at TDC, like explained earlier, each of the marks on the timing gears will line up with a timing gear alignment mark on the cover directly behind them. Sort of at the 10 and 2 oclock positions IIRC. If you can't get the timing gears to both line up at the same time, then they have slipped a tooth on the belt or were installed improperly.

Once you have the physical timing set, look inside the hole on the exhaust cam, thats the one on the drivers side that the CAS mounts to. There is a dowel pin inside the end of the cam facing you that the CAS aligns with. Make sure it's not bent or broken. Broken usually means the car won't start. CAUTION, when reinstalling the CAS, if you break the alingment dowel you're buying a new exhaust cam.

Once all this is accomplished, set the CAS to thein the middle position with the bolts snug. This alone should be close your base timing.

Hook up your timing light to the #1 coil pack. Aim and shoot. Proper alignment should be the orange mark on the pulley. 2nd one from the right as your looking down at the crank pulley from the front.

Someone please review this and make sure I didn't screw it up. It's been 2.5 years since I had set the timing on a RB.

Best of luck man.

WD

[fly240]

hey, WDRacing, this is a very useful instruction. I've been asking for timing help for the past weeks. thanks, without timing tune, those SR motor still right behind the rb, I want my timing tune so I can smoke them like a yellow bird. If any one have any more detail please let us know...

[Carl H]

when i first put in my rb20 its base timing was at 30 degrees (or the last white mark on the crank pulley).needless to say it ran like a bat out of hell, amazingly it never detonated or knocked.put it back to 20, slower in response but safer.i was lucky that no damage had occured.

[eh?]

when i first put in my rb20 its base timing was at 30 degrees (or the last white mark on the crank pulley).needless to say it ran like a bat out of hell, amazingly it never detonated or knocked.put it back to 20, slower in response but safer.i was lucky that no damage had occured.

http://www.skylinesaustralia.c...iming

A lot more threads on SAU about that. It depends largely on the timing light. Your timing could have been correct when you saw 30. 30 would equal 15 which is the correct timing. Was your CAS in the middle when you saw 30?Like i said the best thing to do is use an old spark plug lead on #1 cylinder.

[Carl H]

no trust me it was at 30 degrees, i know the timing is in increments of 5.i dont remember where the cas was but i think it was nearly maxed out, but it had come that way.

[Bluefire]

Don't use the white loop to get the timing. Unbolt the first coilpack from its bracket. Then use a normal plug wire to connect the sparkplug to the coil pack. Now hook up the timing light to the plug wire. This way is much more accurate.

Also what is your idle rpm set at? What kind of timing gun are you using?

-Bluefire

[fly240]

how do you check your base timing.

[armysweitzer]

wow thanks for all the replies (lost power for 2 days) maybe i am wrong about timing but i would bet a good fortune my friends read it write (maybe not 40). I know the car is badly advanced but when its set right it doesnt run right, would that be a knock sensor problem.

1st of all, we did the timing using the 1st sparkplug method, however i will try everything again.

2nd I did hook up the speed sensor but still nothing, i did read something about that plugging directly into the vehicle speed sensor.

My highly experience ka-t, sr friends really think its a knock sensor problem but i could be off..

thanks again for the help, its got me pointed in the right direction. Keep it coming!

PS its nice not to be flamed for some stupid questions, thanks guys.

[Carl H]

how do you check your base timing.

the way i do it is set the cas to the middle, run the ecu thru diagnostics to clear codes and the learned maps and then set timing.i then check it to make sure its right and then go out for a few spirited blasts to get the ecu to learn the power curve.then i check to make sure its not some obcene timing and let it go.

[armysweitzer]

update, car is around 21 advanced timing. We attempted to set it near 15 but set there the car makes no power and drives like it wants to die.

any help is appreciated once again

[goofynick6]

A bad knock sensor will throw a code, so check for any that may be present.

Look for the silver tape on the CAS that was there from the factory. They tape the CAS to the timing cover to kind of show if someone changes it. If you can still see the tape on the CAS and timing cover, line the pieces up and that should be approximate factory timing. I did this and it was just about spot on for where I wanted it timed.

Don't forget to unplug the tps, and I think the problem you're having is that you have to time the car with it idling at 650-700 rpms. Do you have BOTH plugs of the tps plugged in normally? You must always always have the smaller plug that hooks directly to the tps plugged in, the other with the short cord going to it you unplug when you are timing it. This makes a big difference on proper idle and timing.

Also, the neutral switch is very important I have found. If I am cruising and push in the clutch with the car in neutral, it stalls, but if I do the same with the gear selector still in gear, it won't stall because the neutral switch changes the way it idles.

Nick

[armysweitzer]

there are no codes, they were all cleared so unfortunatly another dead end...

Yes we made sure we unplugged the shorter tps plug.

I will check the neutral switch.

[fly240]

how do you adjust your idle, my is at 1000 and above. my wire was done by mckinneymotorsports about 2 years ago.

[goofynick6]

there are no codes, they were all cleared so unfortunatly another dead end...

Yes we made sure we unplugged the shorter tps plug.

I will check the neutral switch.

The one you unplug is the one with the short 5" or so cord on it, not the one that plugs directly into the TPS. The one that plugs directly to the TPS is a switch to show that the throttle is closed and the car is at idle.

To set idle, you need the car in neutral, and unplug the AAC or idle air control valve, then adjust the screw in on the idle valve. There's a possibility your throttlebody plate is set too far open and letting in too much air. You can determine that by unplugging the aac and if that doesn't fix it, then there's either a vac leak or tb plate is open too much.

Nick

[fly240]

where can I find the AAC or idle air control valve, I know there is an adjustment plug that's located at the throttle. I want to make sure I know where it is and what I'm doing...Please let me know...thank you

[goofynick6]

IAC valve is located near back of intake manifold, it has a small gold cylinder and a brown plug coming off it.

[BoostFab]

look at the pic below

[rb240det]

I ran my RB20 ECU through a diagnostic check and it flashed the code for the knock sensor. Does anyone know what sensor is interchangeable with the RB20. It's really causing a loss of power after several minutes driving so I'm trying to source out the problem quick. Hopefully replacing that sensor will solve the issue. Thanks for any help!

[goofynick6]

I bet your wiring is just bad between it and the ecu..I can't see it going bad.

Nick

[armysweitzer]

ok well not to sound stupid but can someone walk me through checking the knock sensor(s) and wiring to see if thats the problem, any help would be greatly appreciated.

Thanks Johann