stormhelix

Hey guys. I've got quite the strange issue.

My 1985 z31 turbo wont start. It ran great before I did this job. It is a 5 speed original from factory.

So a couple days ago I had the coolant bypass hose that is tucked behind the timing belt under the FPR start to leak hardcore. So I pulled the Distributor and moved the plastic piece that looks like a vacuum cleaner head. I unpluged nothing besides a vacuum line from the plenum to the AIV I think. (besides the Neutral side of the battery). Got the coolant hose and replaced it. I put everything back as it was before. I did accidently break the FTS (fuel temperature sensor) spade connector on the old FPR FTS sensor. I got a new one coming, But as far as I know, this shouldnt stop it from firing. Would only make it run rich. P.S my Z was running kinda rich before.

One thing i will say is that I forgot to mark my distributor timing, so I move my engine piston #1 to Top Dead Center, and Put my distributor hammer (whatever it is called) to Spark plug #1. Correct me if this is not the right setup.


So, as with any non-starting car, I checked for fuel, air and spark. I pulled #1 spark plug and cranked, It had a Solid Blue spark. But the plug was covered in gasoline.

Checked #4 also. Same case, Solid blue spark.

Spark is there.

So Next I checked fuel. I can hear the fuel pump work, and the fuel traveling through the fuel lines. There looks like there is petrol coming into the chamber because of the petrol on the plug, But also I could see a small pool on my piston head. (had some carbon buildup.) As well as petrol fumes. I have not been able to check pressure before and after Filter, But will try it soon. (One thing i will say is that when i let off the ignition, it stumbles and almost fires (engine vibrates as if it fired once).

So next I looked at Air, I took off my Intercooler and had my throttle just open draw through a filter. Still same no start issue.

So i started to turn to my Ecu. It gave me these codes surprisingly. I will say again, it ran PERFECT before I did the hose.

Name | Code #
_________________________|___________
Cylinder Head Temp sensor | 13
Neutral park safety | 24
Starter Signal circuit | 32
Load Signal circuit | 31
Ignition Signal Missing | 21
Air Flow Meter Circuit | 12
Crank Angle Circuit | 11 <---(this one i'm not sure it gave me the code for it.)

After I did the hose. My front headlights wont pop up using the button in the cockpit.

also, my Battery seems like it has been dying. I had my Truck charge it for almost 30 minutes, and tried cranking while being jumped (sat at 13.45+ volts connected. Still wont start. It wont hold at 12.3+ volts (could be wrong, have not gotten it to full. But will hold 11.6 volts easy. Could this be a battery issue?

Any help with this would be greatly appreciated. I'm very stumped.

rogerz

I've found the codes to be mostly useless in diagnosing anything. try this

When trying to start without success you can easily inject enough unburned fuel to effectively flood the engine (using old carburetor terminology). this then prevents you from starting the engine normally. If you have checked everything and still no luck try this. disconnect a wire from the fuel pump so it won't pump (on a z31 pull the fuse). you need a fully charged good battery for this. hold the gas pedal to the floor and give it a long crank. you may or may not get a few pops. Do it again. it may run for a few seconds. do it again. When you no longer get any action reactivate the fuel pump and try a normal start.

Get your battery load tested. Be sure you have clean, tight corrosion free terminals on both ends of your battery cables. Be sure the ground (negative) cable goes to a bolt into the frame before going to the starter. grounding through the starter is not a reliable connection. Z's don't like low voltage. causes the electronics to act funny. it is possible to have enough amps to crank but not enough voltage to run the electronics. If you have one size fit all cheapo clamp on terminals they are a problem waiting to happen. Usually on a rainy night around Oh Dark Thirty.

fuel temp sensor does absolutely nothing that I have ever observed after wasting the money to get one for my 85T.
called a rotor. there are two TDC per cycle be sure you picked the right one. Since it ran perfectly before you obviously did something wrong.

stormhelix

OK. I do not have the means to get it load tested right now. So i just hooked up my truck to it via cables.

So i did what you said. I undid my fuse for my pump, it was quiet as it should. I started cranking and nothing, But when I let off the ignition it fires once or just vibrates. Sometimes after i start cranking I can hear a mechanical grind noise on the left of my engine (from in the car driver seat, Sometimes it would happen and Id feel it in the clutch kinda, but not really. Sometimes it wouldn't happen and it would be a clean long crank.) Did that a few times til it would crank with no action. P.S I did depress the Gas Pedel as you said to do.

Redid my fuse, Turn to ignition, Fuel pump activated and pumped. Heard fuel injection, Cranked and Nothing. BUT, i noticed when I let off the ignition, i can hear my pump again, like it was pumping more into the cylinders. (I also smell almost pure gasoline when I crank after reactivating pump. Not exhaust fumes.

Long story short, It did not work, unless I did something wrong. But could you explain the 2 TDC thing? I do not quite understand fully. I know its a 4 stroke, But I had my timing marks (on cams, the little indent) lined up where they should be. I also checked my cylinder 1, by taking out spark plug and looking down #1 spark plug hole and seeing the piston.

Any more suggestions?

rogerz

4 stroke cycle. suck, squeeze, bang, blow. the piston reaches TDC on the compression stroke which is the one you want. It also reaches TDC on the exhaust stroke. if you used the marks you should be okay. Did you give it a long crank? far longer than you would need to just get it started. other possibility is that the fpr went south and your fuel pressure is sky high. you need to get that data. check to be sure your throttle plate is opening. no broken cables from gas pedal. you got spark you got fuel so next thing up is AIR. be sure you are getting it.

stormhelix

Ok. So i did some side testing. OK means in working order.

There was fuel in the lines all the way up to the injectors it seems. Does the fuel do through the FPR before injection? or after? Would a faulty FPR stop the fuel from being vaporized in the chambers?

Fuel Filter: OK
Fuel Pump: OK
Fuel Lines: OK (no leaks)
Fuel lines to rail: OK
FPR: Unknown
Fuel Pressure (psi): Unknown

Spark;
Plugs: OK
Wires: OK
Hard blue spark: YES

Air;
Throttle plate: OK
Plenum gaskets: OK
Vacuum/heater lines: OK (to intercooler piping into intake)

Ignition;
Engine crank position moves during crank: OK
Ignition coil resistance: OK
Spark to Plugs: OK

Timing;
Belt: Seems alright, Almost seems like a tooth off. Hard to tell.
Distributor: Seems on time also. It has a nice long crank, no hesitation.

Hose lines to carbon can;
Purge: OK
Fuel tank: OK

Is there anything between the FPR and the Injectors? Or what can cause the injectors to not fire? Ecu?

As far as I can tell, I am getting fuel to the rails and FPR (not sure if it is getting in cylinders), I am getting Air into the plenum, and I am getting spark on all cylinders.

What the Heck. All I did was move the distributor and move the FPR slightly.

Any help is much appreciated.

thanks.

rogerz

if your plugs are wet why would you think your injectors aren't firing. that is how fuel gets into the cylinder. download fuel injection bible from atlantic z. READ IT. you need to know how the system works in order to trouble shoot it. The FPR bypasses fuel from the fuel ring back to the gas tank to keep a constant pressure on the fuel ring. the injector pulse is designed to give x amount of fuel with the ring at correct delivery pressure. Too high you get too much fuel and the converse for too low. put a gage in after the filter and before the ring. you need a t and some tubing you can get at hardware store, Lowes, auto parts etc. any pressure gage will do. get a cheapo oil press from auto parts. a vacuum gage not a bad idea either if you ever get it running.

how did you move the FPR slightly? it is bolted to the engine. Moving the distributor probably fluffed the ignition timing which may be your entire problem.

if the timing belt jumped a tooth (unlikely) you might start hearing the valves getting hit by the pistons. timing belt should deflect one inch when depressed with a 20 pound weight applied to midspan.

you need to verify FUEL PRESSURE.

can you see the timing marks on the engine pulley? there should be a plate with notches attached to the engine and notches on the pulley. Use that for your TDC mark.

stormhelix

Hey, Thanks for the response, I am somewhat familiar with how EFI systems work, especially fuel return ones. But what I meant by firing is the time at which they fire, and or the vaporization of the petrol.

Also, To rotate my engine manually, Is it best to take out #1 spark plug and #3? or what else would I need to do to be able to rotate it by hand? (never had to do much with timing, never had to rotate.)

Does the Distributor run Counter Clock Ways or vice versa?

Also, like I said earlier, there is a little plastic piece between the FPR and the Distributor, what is that? it looks like a vacuum attachment you'd put on your handheld vacuum. Ive been scanning multiple diagrams and cannot find anything on it.

I will try to get a Pressure gauge today. I assume it would be best to get one that does 0-100psi?

With distributor timing, Even if the timing was off ever so lightly, wouldn't it still fire? just run a bit shitty?

Also, with belt timing, I do not hear the valve touching the pistons. But i do hear a mechanical like grind towards the end of a long crank near the left side of the engine. Almost feels like a flywheel or transmission, but I always put my clutch all the way in during starts. Also sounds like its coming from near the distributor or coil.

I really appreciate your help Rogerz. It is helping me a lot with diagnosing the issue.

thanks.

rogerz

what kind of z31 do you have? your use of the word petrol kinda looks limey, aussie or maybe s. africa. I just looked at my 86T car and my 85T engine and there is nothing between the fpr and the dizzy that looks remotely like a vacuum cleaner mostly just empty space. You can rotate the engine by turning the pulley nut. no need to pull plugs. it does make it easier but not necessary. How can you see marks on camshafts with the valve covers in place. with the valve covers off you might be defeating the maf by not pulling in any air (not sure on that just a thought). think the dizzy runs cw but not sure on that be sure your wires are running to the correct plugs.

depends on how far off the timing is whether it might or might not run.

you have to get it running to time it properly. Need a timing light only way to do it. rotating by hand won't cut it. remember air spark fuel needed to run you are missing one of those.

stormhelix

Hey Roger,

I am Ukrainian by birth, but I live in the United States. I have many Kiwi and Aussie mates and I pick up a lot of vocabulary from them. My z31 is a North American 1985 300zx Turbo.

When i said i can see marks on camshafts, I meant the gears. they have little indents.

Attached in a photo of my Bay, and that vacuum thing.

I've got a gauge that does vacuum and fuel pressure coming into my auto parts store later today. I should have the pressure tonight.

One thing I have been looking into is whether or not my Z has had the fuel injector service done. It looks to me like the rail is oem, same with fpr (looks older than the Rosetta stone), which would leave me with answers to why it failed at 130k. My wiring to my injectors is shoddy at best (looks like a 15 year old civic owner did it. (no offence to 15 year old civic owners and their wiring skills). not to mention my wiring does not have yellow or colored dealer ID tape. It seems like its 3 to 1 maybe, Batch injection. not sure.

Called Nissan and they are searching the older Nissan archives and will get back to me tomorrow morning.

Also, my apologies for the terrible photo quality. My phone takes 4K Ultra HD photos, 13M, or 1m. No middle. 4K wouldnt upload to here. so 1M it is.

rogerz

why is your carbon canister next to your battery? Something has been radically altered on that engine. I think you are using the wrong marks for #1 TDC. when you look down at the engine pulley you should see a metal pointer that points to notches on the pulley. that is what you need to see to get your timing right. whatever that plastic gizmo is it doesn't belong there. those extreme closeup shots are hard to see anything. trying pulling back and taking a wider shot. why is the timing belt tin off?

stormhelix

Hey Roger.

So I was not able to get a gauge today that went up to 100psi without spending close to $100. I'm broke as is.

I want to add one thing, my gas tank is at 1/8 (about a tick past 1/8 to the left). Dont know if they will help diagnostics.

I am ordering a Pressure gauge today.

What would be the next step if I didnt pull 37psi on fuel lines (next step for less, and for more pressure)? and what if I did pull 37psi?

Where should the canister be? by the Mast. Brake cylinder?

Also, Timing cover is off because It was difficult to get to the coolant hose without taking it off. Plus my friend had to hand crank my engine to check my TDC.

I think that this car MAY have been originally automatic. MAY have. Not sure. But it is Turbo from factory (says letter C as 4th digit/letter)

I feel like the reason its not starting is all fuel related. Since I litterally touched nothing but the fuel lines. Could it be Air in the lines?

I am going to test my fuel pump and see if it is even pulling up gas on 1/8 tank by unpluging my fuel line before rail and have it dump into bottle. Is there anything bad with doing this test?

thanks. That's all I could think of questions wise at this moment.

Extra Info:

So i tested the fuel by disconnecting fuel line to rail. Im getting a 1/3 -> 2/3 cup of fuel everytime the pump goes off. So the rail is getting fuel. The cylinders seem too be getting air and spark. So it must be the FPR? I will remove the distributor and re-time it tomorrow morning. ill also go back and trace my steps on the job and see if anything got plug in wrong.

thanks.

rogerz

you only need a gage that goes to 50 psi. your fuel pressure should be about 30 at idle. mine runs 20 at idle (because I changed the stock arrangement) and as high as 40 under full boost (which is 10psi as I am presently set up). carbon canister normally up front under the vacuum tank yours is where the cruise control normally is installed. someone radically re arranged things in your engine room. air in lines only affects diesel engine injectors. because the fuel system in a z31 works off of pressure on the ring and injectors open electrically not by fuel pressure as in most diesel engines air will be expelled through the injectors and you state that all your plugs are wet. means too much fuel being injected. my 86T also was converted from slushbox to manual so that isn't an issue. only difference is there is an oil cooler mounted inside the wheel well on the right side. those hoses tend to ooze at 20 years. just a mess not a problem. Ihad mine redone at a hydraulic place. 250 bucks but I stopped drooling oil every place I parked. pull the hose that returns fuel to the tank from the fuel ring and see if it is blocked. if your problem is too much fuel (which is what I think also) you should get some sort of running with the throttle wide open while cranking.

stormhelix

hey Roger. AGAIN sorry for the **** camera quality, I tried to take a big photo of my bay but because of the quality it is so blurry, that it was not even worth it.

So i was took some pictures today of the vacuum lines and such. I used this diagram (pictures) to help me.

One picture shows me pointing to a coolant bypass hose. That is the one I changed.

All vacuum lines are connected, clamped and sealed. Although I am having trouble locating my AIV solenoid.

ALSO. the golden elbow you see pictured is above my FPR solenoid. On one of the hoes to it. It has MASSIVE amounts of pressure. Couldnt even squeeze it at all, And i am quite a large guy. But the other one I had no trouble. Could it be a fuel shutoff valve? Both pipes go under the turbo side exhaust manifold and follow the same route, As if someone put a shutoff valve in.

Also, My Plenum vacuum is T jointed so I could get a post-plenum vacuum source for my BoV.

One thing I will not is that on the Diagram, there is a blue tube going from top of intake plenum Nut, looks like its at the elbow of the throttle body. My nut that is on top of my plenum has no nipple. And my AIV solenoid is gone as far as i can see.

rogerz

can't make head nor tail of those pics. doesn't look like a stock fpr. I think some meathead with little or no mechanical ability made a mess of the car. all that blue crap for what?

stormhelix

Ill try making better ones.

But I did take apart that valve and both pipes have nothing in them, Nor smell like fuel

-- Where are my return lines? are they the two coming out of the FPR towards plenum?

-- How should I go about checking if my fuel lines are blocked?

rogerz

read the private message I sent you. I can't post pics because it says I overstayed my welcome or something.

stormhelix

Hey Roger. i got no private message from you.

But anyways.

I did another test today to help me find out again whats going on.

I will add that after sitting for 5 days, battery got down to like 3.3 volts. I dont know how.

Also... My headlights wont pop up anymore, after this job.

So I rolled it out of my garage into my driveway. Put the timing marks correct, Put my distributor correctly. Started cranking WITHOUT fuel pump fuse in. Long long nice beautiful cranks, Get a ignition or two (didn't get one before). Constant light pops out of exhaust (in time with ignition). Do this 5 times. (with my throttle open with no filter.)

I think my timing may be off. On the crankshaft, is it the 1st from the right? or the 1st from the left? or which notch is the correct one.

Then I put my fuse back in, and this time, I pressed the throttle and cranked before fuel could get into the engine, Good cranks until fuel started to get into the cylinders, then it started to bog down like it was on low battery, when it shouldn't, since it was hooked up to my truck holding 13.86V for 30 minutes. (cables Red/Black battery truck -> red battery black ground). And i was cranking without fuse for like 30 seconds straight with 10 second rest.

ALSO. when I crank after taking my fuse off, I can smell gasoline in the driver seat area. it goes away slowly.

ALSO. First time I cranked after take out fuse, it fired 2 or 3 cylinders for a second and whiteish smoke exhaust came out my exhaust pipe.

Hope this can help us.

rogerz

tried sending you another message see if that got thru. if so contact me via email