New to Ratsun

[logan66]

I'd say I'm right around 6 inches maybe a little longer with the bend in the stock pipe. My airflow meter sites right next to where the ax comprossor would be from a bracket I made to bolt in where it would be. I think I figured it out though. The plug for the MAS was really worn out and didn't lock into the sensor like it should so I soldered the one from my 77 in on it and I started it up 3 times with a good idle so that was good enough for me. Atleast not to give me headaches worrying about it throughout the week.

[logan66]

well the 1200 to 1500 rpm idle is back.  I have run out of ideas of what it could be.  I know i dont have any vacuum leaks, other than what i posted before nothing else changed except i forgot i put the msa downpipe on.  I check the o2 sensor was plugged in correctly so that shouldnt have anything to do with it.  would me shoriting out the coil have anything to do with it?? maybe with the transistor on the bracket or something else?  To me that doesnt seem like that stuff would effect the idle but im not sure.  Ive been reading online and have seen some stuff about the tps sensor, but i havent messed with that either.  It doesnt make sense to me why its so unpredictable.  sometimes it idles fine and other times it doenst but i dont change anything.  Im at a loss for what to do next so if anyone has any idea at all i will try it but for now i haven't found anything online that has fixed it.  I have continued working on the rest of the car, got the brake and clutch bleed ( after having to put on a new clutch MC from hours of failed bleeding)  and i also got these in the mail last week and got them mounted.

 

 

 

 

Needs lowered and flares put on, i have the flares and hopfully can get my fenders back on and seats put in the car and drive it soon..... but i really hope to get this stupid idle figured out before that.

[CGraves]

Have you checked all the couplers on your intercooler pipes? I've seen them rip in a way that sometime they overlap and seal the gap but sometimes boost would push it open again and when the rubber laid down again it wouldn't seal correctly. I'd pressure test your system and see if you've got a loose coupler somewhere.

[logan66]

I don't have an intercooler, I still have the stock j pipe. I'll check all the connections to that though.

[logan66]

Well, i gave up on the idle for now. I've been reading some stuff about adjusting it with the idle stop screw but need to look more into it.  Anyways I took out most of my interior and installed MSA's molded carpet kit.  It turned out alright beings its the first time I've ever done anything like that.  It's not completely buttoned down yet but close.  I put my old seats in and honestly I kind of like them with the cream colored door panels.  I just wish they weren't so disgusting haha.  I'm going to try and clean them up next weekend.  Here's some oics.  It looks 100x better now and almost like a real car again.

 

 

 

And about twenty minutes later I took it out for a short spin.  I almost don't want to put the fenders back on because it looks like a car out of mad max with the black front end.  Maybe it's just me that thinks that but it's one of my favorite movies.  It was crazy finally getting this car off my dads lift without pushing it.  I've also never driven a turbocharged car but just after a little half block drive I think I'm already addicted to boost.  Anyway here's a video of me driving it really quick.  ( You can also here the high idle at the end of the vid, but honestly I'm so happy to be driving this thing I could care less about it right now.)

 

[Slowpoke]

Good shit man!

[logan66]

Thanks!

[logan66]

Well, fixed the idle. Not really the way i wanted to but it was the last option I had.  After checking all vaccum lines and found no leaks I went with a ball valve idea I found from rickyellow zee on hybrids forum.  I just bought a barbed ball valve from home depot for 10 bucks, took off the air regulator and put in the valve and it works perfect! I can set the idlle to whatever I want now.  I have a feeling it might be running rich since i metered the air way down from what it was and I'm assuming its getting the same amount of fuel but maybe my thought process on that is flawed but idk I'm happy with it and the brass valve doesnt look too bad! (after i cut off the humongous orange handle.)

 

 

Then I worked out a trade for an intercooler and piping for my old n/a l28 with the guy I got the turbo motor from.  I probably wont put it on right away because I want to drive the car for now.  Im working on getting tags/insurance/ and inspected because its an out of state vehicle.

 

 

anddd here's some more pics of the car.  I take pictures of it all the time now :rofl: I'm a little obsessed haha

 

 

 

[Bleach]

That is a good idea. That valve you removed usually runs the idle high when the engine is cold and then closes to drop the idle down to normal levels. So for now you won't have that option but the car can still be used. I think its more important to have consistency when the engine is warmed up as you also know.

[logan66]

Yeah for now it works. Easy to adjust quickly with no hood on

[logan66]

Well, looks like the idle was the least of my worries. Took her out for a short drive, gave er the beans a little bit and looked up at the temp gage and it was buried. :( Gonna drain the fluid and check for any oil in it tomorrow.

[Bleach]

so sad. Overheating is one thing, but if the needle is pegged that is not good. I hope you caught it in time before damage.

[logan66]

Well, found out why my car overheated.

 

Put a new water pump on and Good news is I think everything is fine. For now.  

 

But I took it out for a drive and the acceleration is very rough after about 3000 rpm.  But it only gets rough under load and starts backfiring.  I can rev the car up all day to redline and it sounds perfect.  Maybe a fuel issue?  It has a new fuel filter on it but maybe the injectors need to be cleaned. Ill figure it out eventually but right now I'm just happy it still runs haha.

 

[Slowpoke]

That sucks. Check compression, and check for fluid cross contamination. The heads on these engines like to warp if overheated.

 

If you got a free pass, check out the entire cooling system to be safe.

[logan66]

Well I checked my coolant and it was clean and my oil looked good just dirty Ive read it's supposed to look milky if it has any coolant in it. Also looked for bubbles in my radiator for a Head gasket leak and so far so good. I did figure out the rough acceleration. The hose that goes from the j pipe to the intake was loose so I think it was leaking at higher rpm and more boost. I plugged off both and I got a smooth feeling and sounding acceleration all the way to almost the redline and felt really good. It dropped my idle quite a bit but I'm not messing with it because I will have a different setup with the intercooler this upcoming weekend. I'm going to do a compression test just to make sure but I think she's still alright but it'd be nice to know for sure.

[logan66]

Hey guys,

Well was gonna make a big post how my car was running awesome now even after overheating and now runs cool after I had done all this work too it but I came home today after work because my dad got my car inspected and tags so I can legally drive it. So I guess I'll start in detail of what I've done and what happened and what it's doing now. So I put the intercooler and while I was doing that I adjusted the throttle stop screw to set my idle that way instead of the hanky stuff I had earlier.Ran awesome no boost leaks still rough on the higher rpms. Then I checked timing. At 700 rpm I was almost off the end of the teeth next to the crank pulley that measures degrees. It was basically at 30 degrees advanced so I got it down to 20 at the correct idle rpm. I triple check this so I'm fairly certain it's not a probably anymore. After I got the timing the car revved insanely smooth all the way to redline. Then I installed a boost gage and manual boost controller played with it for a bit and set it to about 8-9 ish psi for now and ran awesome. Today my dad trailered my car to a near by town to get it inspected and get a tag and there was chance of rain so he put a tarp over my hood. I don't know how well he covered it and it poured on my car. He told me the coil got wet. So started the car just fine. Will rev all the way to redline not under load but when I went to drive it legally for the first time right when boost starts to come on if fell on its face and backfired. Now it can't even get into boost and does it every single time. My dad called his mechanic. Told me to check the fuel filter, clean as can be because I had already checked it about a week ago for the rough acceleration. So now I'm at a complete loss on what to do. If anyone has any ideas I'll try anything.

[Slowpoke]

Re-check your work with the intercooler piping, boost gauge and controller. Re-check all of your work. Specs for the coil are in the FSM.

 

Welcome to the Turbo datsun rollercoster ride!

[logan66]

This roller coaster sucks, but expected. I'll try to check that all tonight but it ran awesome after I did all that too it but I'll still re check it all. My dad drained my fuel today and it was a little foggy. Thanks for the suggestions. How likely is it the rain shorted or messed something ip in the afm? I'm not sure exactly how the afm works but as the flap moves it sends signals to the each for longer pulses for the fuel injectors right? Idk I'm just pondering over all the possibilities at work.

[logan66]

If I used the idle stop screw to set my idle and didn't adjust my tps could that be causing the issue. I read threads of people doing it but I've just been thinking about what I changed since the last time I drove it and I saw a thread that said it needs to be adjusted if you set your idle off of the stop screw. But I didn't think anything from the tps would make my car do that?

[Slowpoke]

Start at ignition. Check plugs, wires, dizzy cap, rotor, coil, ignitor, and all associated plugs. Check all vacuum lines, IC piping, intake boot, etc. Continue checking systems in this manner. Go from easiest to the more difficult systems and components.  This method may take a long time but it usually turns up something, and is faster than guess and fiddle.

 

Good luck homie

[datzenmike]

Water is not very conductive for only 12 volts, but the high tension voltage from the coil, wires, cap or rotor is a different story. Check clean and dry anything on the high voltage end of the ignition. Remember, the only thing that really changed was it getting wet. Voltage will ALWAYS try to find the easiest shortest path to ground. With good cap, rotor and plug wires this will make the easiest path to ground across the spark plug gap.

[logan66]

Well I made some progress, new coil made the car run a lot better still backfired a little bit but could kinda get into boost.  So I got new spark plug wires and spark plugs. NGK-R's but they really didn't change anything so I kinda took a break and stopped messing with it.  Saturday I got into the car and it ran awesome, out of know where.. so i thought.  Today my dad told me that he banged on my ignitor ( he doesnt know what it is but it also got very wet beings it was on the coil bracket so I guess that was what his primitive brain came up with lol)  but it worked? atleast for that little pull i did in the drive way.  Anyways today it ran a little worse but just like it used to with random misses.  I don't know why him doing that helped because my understanding of the ignitor is basically like a small transformer to hop up the ecu signal for the coil, but whatever it kinda worked but he said  he banged on it because thats what we did with the fuel pump to get it to work haha.  Anyways I got a no name gm 4 pin hei module to replace it because i think thats what causing my problems.  I was following this write up wiring it up.

 

 

So I wired it up just like that but it didn't work.  So I googled it and I didnt know the metal back plate of the ignitor acutally served as another ground so from my findings on forums if that back part isnt grounded then you fry the unit:/  lol i guess its my fault for not researching it more.  Anyways I was wondering if anyone had any other info i should be aware of so i dont ruin another one.  It was only like 20 bucks so its not a hige deal but id like this one to work next time.  Anyways with the knew one as long as i have a good mount for the ground on the back plate it should work?  Was that the only thing I was missing?

[logan66]

Well its been awhile since I updated this because I've been in school but i have the day off today for labor day.  I've made a lot of "discoveries" so far on why my cars not running right and hopefully enough to were someone could help me narrow down the problem.  I went through all of the ignition, converted to the hei module then back to the stock ignitor because it didn't change anything and looked ugly lol but now i have a back up if it ever goes bad.  But when replacing my spark plugs i ran the car a couple of times and pulled out cylinder #2's plug and it looked brand new and didn't smell like gas or anything.  So i grounded out the plug outside of the cylinder and it definitely is sparking.  So I thought that the fuel injector was bad on that cylinder or the plug from the harness itself.  So i swapped the 1 and 2 FI plug and the #2 was sending the pulses to injector 1 and it was firing so i took the fuel rail out to inspect the second fuel injector.  It was pretty clogged up so i clean it up and put it all back in.  Which at that point i thought i fixed the problem... for about 3 days then it went back to running terribly gradually.  Each day it seemed to get worse and I'm back to where i started.  Then messing around with stuff today i took out all the plugs just to see what they looked like and they all were very white/ lean looking.  So I remembered reading about the CHTS and that unplugging it would make it run super rich. So i started the car unplugged it and it definitely runs rich cause i could smell my downpipe during right underneath me.  But i took it out and it ran like a bat out of hell and was awesome haha. But it died after hard acceleration coming down in RPM.  So from what I've been reading this could lead to my AFM possibly has gone bad or the connections itself?  I wouldn't think the CHTS is bad because it would act as if it was unplugged all the time if it was bad right?  Then i also read it could be the TPS sensor and mine is definitely not set right, I tried to adjust it when i used the idle stop screw to set my idle but i couldn't read any continuity between the two pins no matter how i turned it.  Maybe thats not the right way to set it but from my understanding where the blade sits now it should be in contact with the other pin and loses contact when you give it throttle and then it switches to "off Idle".  I don't the the TPS is my problem because i changed the idle to use the screw like 3 weeks before it started running bad.  This is a pretty long post but hopefully the CHTS info might tip one of you guys off on what my problem is that i can't find.  I really want to get it fixed because it ran awesome with it unplugged, such a fun little pull haha.  But if anyone has any ideas I would really appreciate the help! Thanks!

[logan66]

Well I took my AFM back to school today and used our measurements lab DMM to test my AFM.  I found that it passed all the ohm test except one between pin 34 and 33 the specs of the manual say 280-400 ohms and the DMM read a solid 200.  Would the 80 ohms of resistance its lacking in those pins really make the AFM not function? I don't really know what those two pins are doing in relation to the meter but they are out of spec.  I'm going to call msa tomorrow and see about sending mine in to get a reman'd one from them and if they have any advice on the test I took, but I figured i'd ask on here too to see if any of you have any good info, thanks!

[Bleach]

http://www.bleachgarage.com/documents/280zfuelinjectionbook.pdf

 

http://www.bleachgarage.com/documents/280zx_EF_Engine_Fuel_System.pdf

 

http://www.bleachgarage.com/documents/280zx_FE_Engine_ControlFuelExhaust.pdf

 

download