1994 Nissan Sentra SE-R going VEMS, then turbo.

[rob@vems.co.uk]

Remember to type byebye in the terminal program after the mde02 command or MegaTune wont connect afterwards.

Rob

[BenFenner]

What if I just hold the key in the on position for 60 seconds to warm the o2 sensor up, then try to start the car? Will that produce the same results, and allow the car to go into closed loop mode?

[rob@vems.co.uk]

The ecu doesnt drive the wideband until the engine starts to turn, from that point you have about 60seconds of sensor warm-up time so you need to set the Warmup time value in Settings->EGO Control screen, then set the Min temperature value accordingly.

Rob

[BenFenner]

I have idle good enough to where I won't be messing with it until I solve other problems.
I think I have cold start mostly taken care of. I had to up the idle at cranking to give more air, and upped the fuel during cold cranking as well. It's hard to get it any better with my starter the way it is, so I've gone and put in the order for a new starter again. We'll see if I end up needing a new battery too. =/

I'm also getting a random misfire at higher rpms. It happens infrequently, and I haven't found any way to reproduce it consistently, so I'm working on that as well. I've lowered my coil dwell time from 3.0 to 2.0, and now it's at 1.5 and it's still happening. We'll see.

[BenFenner]

About that random misfire at higher rpms...

It turns out I had wires in the engine bay I never really took care of, and they were grounding out causing the misfire. So, that problem is solved.

Things are looking up. We'll see how cold start works with the new starter.

I still have some VE table tuning to do, but once that's done I'll be posting my tables and settings for other people to use if they have a similar set-up.

Also the benchmark races I mentioned earlier should go up. And more pictures will be put in my previous posts to flesh them out.

I know I've said this before, but I don't foresee any more problems as long as I'm N/A. Once I go turbo, we'll see. =]

[rob@vems.co.uk]

I took delivery of an SR20DE last night which is going to be used as a stop-gap until my HUGELY delayed built engine is finished.
The engine came with a complete loom, ecu and distributor, so it struck me that I'm going to be able to use much the same setup as you've done here (unless I make a complete new loom for fun )

[BenFenner]

There are a ton of extra wires going to the distributor, [power transistor and that resistor] that can and should be eliminated. I didn't go into detail in my thread as the wiring kept changing, and it got pretty complicated. Once going COP it's all very simple. Good luck with that. You should have a lot less to deal with if your motor is RWD.

[rob@vems.co.uk]

The big issue is finding the damned wiring info.  The engine is from a 1997 180SX Type-S, which seems to be one of the great 'forgotten' cars because it was being built at the same time as the newer S14 200SXs but is the old shape S13

You didnt use the igniter transistor then?  Hmmm  I was planning on using a stepper driver on that to start with, all depending on the CAS disk of course, the easiest course of action might just be to make a custom loom.

Rob

[BenFenner]

First you'll want to see which distributor you have. This being a RWD engine, I'm not sure what you'll get. I'll tell you what I had. On the 1994 engine I had a distributor with a CAS inside, but the "power transistor", "resistor" and igniter coil are external. The newer style of distributor has the "power transistor", "resistor" and igniter coil built in. You're going to want to find out which you have, and wire accordingly. It should be very easy to modify the stock harness to work with the distributor either way. You'll just need the correct wiring diagram. It's more than likely you'll have the new style of distributor, and you'll need the new wiring diagram, which I think you've actually posted on these forums at some point. =]

I guess, at the end of the day it doesn't matter what you do. I know for sure you don't need the power transistor or resistor at all to make the coil work with VEMS. Just let me know if I can help you with anything. Hopefully you'll have the CAS separate from the distributor, so you won't have to go to COP. That is unless that engine had COPs to begin with. But then why are we talking? =]

[rob@vems.co.uk]

The distributor has the CAS, ignitor and it looks like the coil too!
I'll probably go to wasted spark coil packs and use the standard S14 CAS.
None of the new type schematics have a distributor on them
Only your ones do!
Rob

[BenFenner]

I could probably find the pin-outs or recall them from memory if you want to use the distributor. If it has the CAS built in though, I would jump straight to COPs. It might be possible to work it out otherwise on the RWD engine, but I don't think it's worth it when COPs are so cheap.

[rob@vems.co.uk]

I'm 90% sure that I'm going to bin the entire loom and use a V3 harness, then I'll have an unmolested stock loom

Rob

[BenFenner]

I'm still trying to diagnose a couple things.

I have random break-up (no spark), which goes away when I push down on the COPs. I'm pretty sure I've got this problem figured out, and the solution.

Also, cold start is still being a bitch. When I get the new starter, this should be solved quickly.

Next is an LCD problem, which I won't get into here, as Rob doesn't recommend the LCDs.

I had a question about the tach though. Both Dan and my installations have exhibited this behavior at one time or another. Mine is more prevalent, as I turn VEMS on and off very often trying to start my car when it's cold. Sometimes when I try to start my car and it fails to start I'll leave the key in the on position, and the tachometer on my dash will jump to a random position sometimes pegging the gauge. The tach needle will stay at that specific number until I hear stop hearing electrical buzzing (I'm pretty sure it's the fuel pump shutting off). What do you have to say about this Rob? I've sort of been worried about what electrical damage might be caused by this, or what this might be a symptom of.

[rob@vems.co.uk]

I'm still trying to diagnose a couple things.

I have random break-up (no spark), which goes away when I push down on the COPs. I'm pretty sure I've got this problem figured out, and the solution.

Also, cold start is still being a bitch. When I get the new starter, this should be solved quickly.

Next is an LCD problem, which I won't get into here, as Rob doesn't recommend the LCDs.

I had a question about the tach though. Both Dan and my installations have exhibited this behavior at one time or another. Mine is more prevalent, as I turn VEMS on and off very often trying to start my car when it's cold. Sometimes when I try to start my car and it fails to start I'll leave the key in the on position, and the tachometer on my dash will jump to a random position sometimes pegging the gauge. The tach needle will stay at that specific number until I hear stop hearing electrical buzzing (I'm pretty sure it's the fuel pump shutting off). What do you have to say about this Rob? I've sort of been worried about what electrical damage might be caused by this, or what this might be a symptom of.

Cold start is a pain to do as you only get one chance a day to make changes.
As for the tacho doing that... I've never come across that on a Hall trigger setup - with VR on unshielded cables I've seen ignition events cause that sort of behaviour, where is the buzzing coming from?

[BenFenner]

I'm pretty sure the buzzing is the fuel pump.