SR20DET S13 - cannot connect consult.

87calais · Post by **87calais** » Wed May 20, 2009 9:28 am

Hi,
Helping a friend of mine with his S13.

Car was running rough and the mechanic put it down to leaky injectors. Since new injectors were on the cards he wanted to go bigger to support future mods. Got himself some Sard 550cc's and Nistune.

He has had Nistune installed (By Matt i believe), he had to wire in the consult port as it had been chopped from his harness. When he tries to connect to the ecu with the laptop, it attempts to connect on several ports, then says "consult not connected".

Checks done so far.

We double checked the wiring for his consult port, all connections are good from the pins in the consult port to the pins in the engine harness.

Checked that the PLMS consult interface shows up in device manager with no errors. (shows up as COM14)

When you turn the ign on the red light on the ecm lights up and stays on

Set nistune "nissan ecu communications port" from Auto to COM14 - no difference.

Wanted to rule out the ecu being in limp home mode, as i read somewhere that that will stop consult communications. I know the ecu side of things would be right as Matt would have tested it before sending it back, so we started the car, (old injectors still in) idle wasnt too bad till it warmed up a bit, then got pretty rough. I unplugged the AFM, the car spluttered for a second then idled nice, wont rev past about 2000rpm though. Plugged the AFM back in and we went back to the rough idle. So i guess its not in limp mode - actually runs better in limp mode!.

Tried to put the ECU into diagnostic mode, following a guide in a scanned copy of a factory service manual, it said to start the car, turn the diagnostics pot in the ecm all the way clockwise and the LED should flash 4 times, we did this and got no flashes from the LED. However that manual also talks about a green LED, and his ECM only has the 1 red LED.

Any ideas on why we cant connect to the ECM? tips or pointers?

I have been playing with VL's and RB30's for years, but these SR's I'm not so sure on.

Thanks in advance,
Scott.

XR Pilot · Post by **XR Pilot** » Wed May 20, 2009 8:54 pm

Have you tried connecting to the ecu with the engine running? I've had it happen once with an SR I wired in the consult port, must have grabbed a power feed that was only on with the engine running.

Matt · Post by **Matt** » Thu May 21, 2009 1:42 am

When you attempt connection, does the consult cable light flash during the COM port search and connect?

It must do this for it to write to the ECU

Is the RED led steady when its on? Does it flash or go off then engine started?

Trying to work out if its in limp mode

You can check the board is still installed okay (remove lid and check)

Worst case move CJ2 back to CJ1 jumper on reverse side of board without Type 3 installed and check then if it connects to the ECU

87calais · Post by **87calais** » Thu May 21, 2009 8:57 am

Have tried to connect with just ignition on, and also engine running.

I know the there is a red light on the consult cable, but I believe that its just a power light, and was on while ever the consult cable was connected to the laptop. He tells me that TX light flashes but no RX light, but i haven't double checked this for myself.

With the Ignition on, the red LED in the ECU stays on constantly, however with the car running it is off constantly.

I pulled the lid off and the board is still fitted nice and snug. I'm not sure if he has the factory ROM or not. Or do you mean to remove the Nistune board, change the jumper and see if it will connect with no ROM at all in there?

Thanks
Scott.

Matt · Post by **Matt** » Thu May 21, 2009 10:28 am

If the LED is off whilst the car is running then it shouldnt be running limp mode, which means the board should be running okay

If the light is flashing on the consult cable when the 'consult' button is pressed then it is talking to the computer so the PC is okay

That just leaves the consult plug hooked in ... if there is no response from the ECU

PL · Post by PL » Thu May 21, 2009 10:28 am

Hey Scott,

So the ECU isn't in limp home mode - tick. That's the main reson for not being able to connect. The USB drivers for the consult cable are installed correctly - tick. That's the 2nd main reason.

We need to be sure that the data is going from laptop to the ECU - so just check that the green LED does in fact flash. If this is happening then there must be some reson why the ECU isn't responding. I know you said that you checked the wiring to the consult port but I'd be double checking this cos it sounds like the problem to me.

If the engine wiring has been messed with then it also pays to check that your earths are good. I've seen engine conversions that have trouble with consult comms because of bad earths - although they can usually connect but then have troubles with noise when the engine is running.

Check the two earth lugs for the EFI loom on the rear of the inlet manifold. Also check that there's a good earth from battery to chassis and chassis to engine.

PL

87calais · Post by **87calais** » Fri May 22, 2009 12:39 am

Thanks for the quick reply's guys. He is away for the weekend, but when he gets back we will go over it and i'll double check the consult port wiring and all earths.

Will let you know what i find.

Scott.

87calais · Post by **87calais** » Fri May 22, 2009 1:10 am

Could you point me to a pinout diagram so i can check they are connected to the right places.

Scott.

Matt · Post by **Matt** » Fri May 22, 2009 11:29 am

its in here along with testing procedure

http://www.nistune.com/docs/Installatio ... ostics.pdf

87calais · Post by **87calais** » Fri May 22, 2009 9:57 pm

Thanks Matt.

87calais · Post by **87calais** » Mon Jun 01, 2009 10:11 pm

Just an update, He went over his consult port install and found he had messed up the power and Earth connections. Got it fired up and running, consult connected etc, all looking good.
He swapped his injectors over to the new Sard 550's, but the new plugs supplied with the injectors wont clip on properly, they hit on the fuel rail. Is this normal? He said it would be possible file a bit of the plastic off the body of the plug to make them fit, but it doesn't sound right to me. Is it possible they are the wrong injectors? They are a red injector, the stock ones removed were purple. The new injectors came with a small metal collar which he says he tried both ways with the same result. I would think that new injectors and new plugs should fit straight up!

Any suggestions or ideas? I just told him to ditch it and slot an RB in there!

Legionnaire · Post by **Legionnaire** » Tue Jun 02, 2009 2:42 am

You are talking about sr20 right?
Putting RB in there shouldn't help - unless you are talking about ancient RB20, price-through-the-roof RB26, or hard to find Neo 25, RB has exactly same sidefeed injectors, so instead of filing 4 connectors your friend will just have to work on six

Oh, and swapping to VG30 or VH45 won't help for the same reason

Seriously, though, I don't see any problems in filing of the connectors - actually, you don't unplug them often, do you? If done right, it's a fit and forget affair, so if filing does not cause short circuit, it will be okay. To ensure good protection from corrosion you can use silicone sealant on them.
Another approach is to try to rotate injectors to orient them such that connectors don't hit fuel rail.

My friend's sards (RB25 Neo/VQ35 set) bolted straight it.

PL · Post by PL » Tue Jun 02, 2009 10:55 am

Yes, Sard injectors are ALWAYS the wrong injectors on an SR. I hate them. They were obviously never designed for the SR20. All they've done is take an off-the-shelf injector and made it fit using a half-assed system of adaptor collars and oversized O-rings. Very nasty.

And to top it all off they use different connectors, so the std SR20 connectors are usually chopped off and Sard connectors fitted. That's why you can pick up Sard injectors cheap for SR's.

Unlike the JECS injectors which slot straight in.

PL

87calais · Post by **87calais** » Tue Jun 02, 2009 1:52 pm

Thanks guys. I'll pass on the good news. Tell him to get the file out and start modifying the new plugs to get them to fit!

Legionnaire · Post by **Legionnaire** » Tue Jun 02, 2009 5:01 pm

Maybe instead of cutting and soldering existing harness it is a good idea to acquire a spare injector harness off any SR20 and modify it if for example he desides to get rid of sards/car later