Welcome to the SR20 Community Forum - The Dash.
Register
SR20 forum logo

Thread: Another car and what a mess

+ Reply To Thread
Posts: 1-10 of 16
2019-09-26 17:54:45
#1
Another car and what a mess
I wasn't able to give some feedback or tell what I have learned or have excluded. Since I had the oportunity to buy another Nx2000 for 200 dollars I did. There are also quite some good parts there.

So I drove about 500 miles with it and besides the rust, showing neglect all over the place besides fluids, filters and even a new clutch and so on. Not a car to expect to break down but it did.

I own two cars and this 200 dollars scrap car, it are a Nissan Micra March with a GA16DE and two Nx2000's.

So the main Nx2000 gave up on starting and does the click-click. To be investigated.

The other Nx2000 drove me back home and then a whining noise I heard. Trying to locate it, it was the green relay at the ecu. Doing my homework I wasn't able to figure out what it is used for.

Here is another youtube, it is the other Nx2000 and while not recorded it does the same click-click. I wasn't able to connect with Datascan. This car does have a working starter but the fuel smell tells me it has no spark.

Nx2000 relay at the ecu complaining

The relay starts complaining and it does so without the car key put in. When I set it to on position the complaining stops. However it cranks but no start, huge fuel smell.

What is that relay used for, is not being able to connect with Datascan a clue and what steps I should take to diagnose? Three cars and nothing that runs I did read fsm but it seems to be not helpful or I might be missing something.
2019-09-27 05:08:34
#2
My first post was at night and I was trying to fix my issue by using a fog lamp relay replacing the green relay located at the ecu. That might be not so wise to try it straight away so I took by hand the fsm and some terms that are confusing me showed up, ecm relay, fuel pump relay and by http://nissan4u.com egi relay.

I could not find a trouble diagnosis for car cranks but does not start, the only trouble diagnosis I could find is in EF & EC, but those only describe drivabillity issues, is it correct fsm has no trouble diagnosis for a cranking car that does not start?

For swapping a blue fog lamp relay for the green one at the ecu, a post on Nissan Titan forum confirmed that should work and probably it does. Not so willing to try this yet, the fsm tells on page EL-4 a blue or green relay is a 1M relay and are the same. I did read somewhere on the internet the blue relay lacks a diode to prevent spiking for the ecu but the fsm does not mention that and I did try a blue relay but the symptoms are still the same, so I expect it not being the relay but will investigate further.

But an egi relay, could you please tell me if I'm looking at the correct place at nissan4u, http://nissan4u.com/parts/100nx/el_b13/1990_12/type_9/body_electrical/relay/ it just shows a relay but it looks like it is held by a metal plate and I'm quite sure this only can be the relay on top of the ecu.

For Datascan, I can not let Datascan find the ecu and I did this succesfully before so that worked. Could you tell me where I can find this relay in the schematics, I'm a bit lost there, the symptoms tell me it is something different but with my electrical knowledge I can not think of a reason why that relay starts complaining, it stops complaining when the ignition key is in on position or started and why the ecu isn't to be found. I'll start to try to find more about egi relays from here.
2019-09-27 07:35:44
#3
My first guess is that relay is the fuel pump relay. However looking it up to confirm I'm seeing that it is the ECCS relay (or similar). Basically it is the relay to give power to the ECU. That relay is likely the problem.. If not, the ECU itself is probably bad. Those are your two main options in my opinion. That or a wiring problem having to do with the ECCS wiring.
Maybe re-seat all of the fuses while you're at it? The relay is switched through a 25A fuse and the power supplied through it is on a 30A fuse.

The ECCS relay is fed power from the batter to two terminals through a fuse. It then grounds through ECU pin 4 to then provide power to ECU pins 38 and 47. Pins 38 and 47 also provide power to the CAS and MAF. The car won't start with that relay misbehaving, that's for sure.

Yes, the FSM has diagnostic steps to take if the engine cranks but doesn't fire.

Last edited by BenFenner on 2019-09-27 at 07-39-00.
2019-09-27 07:45:24
#4
Oh, your battery is also very weak. That can't be helping the situation... It's not your main problem, but try to work with full power.

I like the blue relay swap idea. I'd do that first to help diagnose. Simple, easy, quick, and cheap. I confirmed the FSM thinks the green and blue relays are the same (or nearly so).
2019-09-27 10:16:22
#5
The blue relay swap gave a similar relay complaint. Hearable in the movie my newish battery drained way to soon. It's charging right now. However today it just clicked once which is a good sign and still the car acts like it has no spark. I'll study your information. Could you please tell me what page you have looked at?

Here is mine,

pdf page 927

First I'll sand the battery minus to the chassis, reading on the internet several people pointed out that was the problem. Now that would add up to the real bad weather, I had to speed down to half of the maximum speed and it still wasn't very safe. After a lot of rain the car started to run on three of it's legs. I brought it to a gas station close at my house and waited a bit and expected to find lot of water but the original spark plug wires and the coil wire and also that cap over the distributor all there, no signs of water though.

Then the car was able to run on all four legs again, slowly drove home. Parked my car, turned engine off. A complaining relay noise. This day, it doesn't seem to complain but still no ecu signs. And my other car I also have no ecu sign.

Is it possible the ecu isn't activated at all or is that not making sense with that relay clicking again. I'm still a bit lost. I'll post what I will find. That might be a better symptomps checking and I'll be after fsm cranking car not starting.

Last edited by richardwbb on 2019-09-27 at 10-23-06.
2019-09-27 10:22:11
#6
Oh by the way, did you mean that Diagnostic Procedure 4 - Hard to Start or Impossible to Start when the Engine is Cold, EF & EC 434, pdf page 897?

Oh and another thing I'm wondering, with a dead fuel pump it should give a working ecu?
Last edited by richardwbb on 2019-09-27 at 10-27-48.
2019-09-27 19:13:45
#7
I have narrowed things down. The story is heavy rain, car runs on three legs. A small amount driving back home, about two miles it attempted to run on four but not really. No traces of water found around the spark plug wires, coil and cap but then that complaining relay I posted in a youtube.

I sanded down masses, the two at the headlights and the two at the throttle body but I don't expect those do much. The grounding of the minus pole cable was quite bad. I sanded a bit with a powertool and it is a car that can not be saved and I did it quick without removing all the necessary parts for it.


The other bad ground or connection I also fixed


Now the car starts and defaults to the behaviour I got in the first place, it runs but it are three legs
Nx2000, starts after solving ecu not connected and relay sounds, but still doesn't run right

For the idling sound it isn't audible on youtube but a Sr20 running like this, what does that tell you? https://fotobakje.nl/map/nissan/b13-rough-idle.wav
2019-09-28 07:41:35
#8
That's good progress to get the car starting again. Was it just cleaning up the electrical connections that fixed it, or did you also have to replace the relay?
There are a couple more engine grounds you might clean up to help things along. And the grounds by the throttle body, do you mean the two on the intake manifold that ground the ECU? Because those would be important to check.

It sounds like it's running on three cylinders, like you said.

Next thing to check would be to figure out which cylinder is bad. You can do this by letting it idle and then removing the spark plug wire from cylinder 1 and listening for the idle to get worse, then plugging the wire back in. Repeat these steps for each cylinder and the one that doesn't cause the idle to get worse is your problem.

Once you know what cylinder is the problem, you can check spark at that cylinder. Do this by pulling the fuel pump fuse while the engine is running. This will kill the engine and drain the lines of fuel. Once that's done you can remove the spark plug in question and rest it on top of the valve cover while being plugged into the spark plug wire. Ground the plug to the engine with a short test wire with alligator clips. Then crank the engine over and watch or record the spark plug. Look for a strong blue spark on the plug. If you're getting weak or no spark there, swap the spark plug with one from a different cylinder and re-test. This will let you know if the plug itself is bad, or if it's the wiring.

If the spark plug is firing strong, then reinstall the spark plug and plug the fuel pump fuse back in. Next up is to check the injectors. Do this by removing the rail with the injectors still installed along with the fuel lines. Leave the rail resting with some rags by each injector to catch the fuel. Crank the engine and watch or record to see if each injector fires in the correct order, and with a good spray pattern. Pay special attention to the cylinder you think is bad.

If one of the injectors doesn't fire, then swap it with one of the other injectors and re-test to make sure the injector you think is bad continues not to fire, or if the one you swapped it for stops firing now. This will let you know if it is the injector itself, or the wiring.
Last edited by BenFenner on 2019-09-28 at 07-46-56.
2019-09-28 08:40:47
#9
That is genious Ben. It is quite a tip you gave there and I'll print it and have it handy with my car. Another friend let me know lacking an assistant, fixate the throttle to let it run. It did idle roughly yesterday but as it seems I made the part of the engine that still worked good enough better because now it won't idle. I'll also warm the engine, to see if that helps the bit that I need.

Here are some pictures, because of heavy rain progress is slow.

Cylinder 2 and 4 bad combustion.


Distributor cap has corrosion.


This much.


The fouled plugs and the outward connector points with the greater amount of corrosion relate. Car does start with open throttle but now I'll follow your tips over the tips from a former Nissan mechanic

I'm reluctant to swap parts from my other Nx2000 that won't crank and I also wasn't able to pin point the problem any further. The click-click I did hear with this scrap car that does start but misfires so I might get to a point I can search for differences by measuring for example. But first step is to get myself a running car that I need for my work. I sure do hope I do not have to swap parts with both cars not starting or not running.
Last edited by richardwbb on 2019-09-28 at 08-46-59.
2019-09-28 10:06:39
#10
You could try lightly sanding the internal posts of the distributor to remove some of the corrosion to at least get things working a little better so you can diagnose more.
Do the same for the rotor blade.

You can also hit the spark plug electrodes and grounding straps with a gentle wire brush to freshen them up a bit as well.

(When I mentioned swapping parts earlier, I meant from the same car. So just swap the plug(s) around and see if the problem follows the plug or not to determine if the plug is the problem or the wiring further up the chain.)

Good luck.
+ Reply To Thread
  • [Type to search users.]
  • Quick Reply
    Thread Information
    There are currently ? users browsing this thread. (? members & ? guests)
    StubUserName

    Back to top