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Re: 1983 URQ Alpine White/Mocha 20VT / VEMS / EFR
Posted: Thu Oct 11, 2018 9:09 am
by Afterthought
Yeah I’ve basically been doing exactly what you described except a little more looking at logs and less doing it while driving myself since I’m alone .
I’m holding each cell for as long as possible then refer to logs , adjust, drive again. Using hills, brake, different gears , long stretches of road . Everything is good except the areas I haven’t been yet . Higher KPA and RPM cells.
Regarding the injector settings . The ECU was supplied by Marc and base tune was in there but I didn’t change anything besides the req fuel parameter .
Sent from my iPhone using Tapatalk
1983 URQ Alpine White/Mocha 20VT / VEMS / EFR
Posted: Fri Oct 12, 2018 4:33 pm
by Afterthought
With over 500 miles now on the car I put 'er back up on the lift and did a good look over everything.
Probably not necessary but I changed the oil again.
Re-torqued the head studs.
New Valve cover gasket. "new" (Less old) oil cap that hopefully wont leak.
New spark plugs. Old plugs look whiter than I would have expected.
I also tried to see how difficult it is going to be to make a new radiator shroud to fit with the radiator I have. Not easy , I don't think its possible to do with just bending, but I could make it in a few pieces. Made a little template that I can look at later and mess with a little.
This is what i have for now. It's trimmed to ensure it doesn't interfere with the throttle cam. The last thing I need is the throttle to stick open on this little go kart.
New tires.

Re: 1983 URQ Alpine White/Mocha 20VT / VEMS / EFR
Posted: Fri Oct 12, 2018 7:37 pm
by Afterthought
So I did drive while logging as usual but this time I tried recording a triggerlog.
If I analyze the triggerlog, what I'm seeing is no issue at times (at idle for example) but once I drive I am starting to get a "Missing tooth" . But its not repeating, it's like tooth 1 , 2, 77, 75 , 12 ... and so on.

I just put the flywheel in so i doubt any teeth have disappeared but I need to look in to what the causes could be for this alarm.
Crank sensor is brand new.
G28 is not new but I never hear of them failing (maybe they do?)
For starters I can pull the sensor easily and see if anything is stuck to it since it is magnetic.
Re: 1983 URQ Alpine White/Mocha 20VT / VEMS / EFR
Posted: Fri Oct 12, 2018 8:45 pm
by PRY4SNO
Any reason you're using a plug range colder with the 7s on spring pressure? What's not ideal with the BKR6E to not use them?
1983 URQ Alpine White/Mocha 20VT / VEMS / EFR
Posted: Fri Oct 12, 2018 9:28 pm
by Afterthought
Duplicate
Re: 1983 URQ Alpine White/Mocha 20VT / VEMS / EFR
Posted: Fri Oct 12, 2018 9:30 pm
by Afterthought
PRY4SNO wrote:Any reason you're using a plug range colder with the 7s on spring pressure? What's not ideal with the BKR6E to not use them?
Most likely just my mistake . How I ended up with the plugs is I just replaced what was in there with new set of the same . Somehow I had come up with the number BKR7E or EIX .
I had never had any issues with NGK whatsoever so I just stuck with them but I never run big power either . I do have a set of Denso plugs and I tried those and noticed no difference .
How’s your build going btw ? I was just looking through your thread .
Re: 1983 URQ Alpine White/Mocha 20VT / VEMS / EFR
Posted: Sat Oct 13, 2018 11:48 am
by PRY4SNO
Nothing wrong at all with those NGK plugs (that's what I ran religiously on my A4), just noticed that you were running the 7s where a set of 6s ought to be better suited to your (current) power levels is all.

The 7s should come in handy when you turn up the wick on your EFR.
Build's gone stale, been investing all my time and energy into the farm. Working on getting the cars, parts and tools out here so I'm not an hour away, which should help get me tinkering again. Thanks for the gentle prod though, a little outside motivation always helps!
Re: 1983 URQ Alpine White/Mocha 20VT / VEMS / EFR
Posted: Sat Oct 13, 2018 1:59 pm
by Afterthought
That farm looks like an incredible place to be .
If you want a gentle prod of motivation fly into battleborn and check out everyone’s car , ha. I did that a couple of years ago- since none of my cars ran, it helped.
As far as turning up the wick hopefully I will do that Soon. I have to put more miles on the car and figure out what’s up with the trigger error then I should be good to do. Driving with break it mode is like torture . Waiting until just when the car is about to come alive then shifting and having the boost limited.
1983 URQ Alpine White/Mocha 20VT / VEMS / EFR
Posted: Sat Oct 13, 2018 6:21 pm
by audifreakjim
Here are the things to check when you have trigger errors
-swap sensors
-swap sensor wires around. I know vems can be picky about this
-adjust sensor depth
-make sure the sensor wires are well shielded
1983 URQ Alpine White/Mocha 20VT / VEMS / EFR
Posted: Sun Oct 14, 2018 8:57 pm
by Afterthought
audifreakjim wrote:Here are the things to check when you have trigger errors
-swap sensors
-swap sensor wires around. I know vems can be picky about this
-adjust sensor depth
-make sure the sensor wires are well shielded
Thanks for the advice Jim.
Man this VEMS setup has been a pain.
I’m sure it’ll be worth it once I get it sorted .
What it’s doing right now is , VEMStune is only showing a red flag for “too many PR trigger” every so often . A lot less than every time I drive the car . But if I do a triggerlog I am a “missing tooth” message every once in a while . I believe it’s a certain RPM range .
So I pulled and cleaned the Crank & RPM sensor first , and that did not change the issue .
Second I replaced the crank and RPM sensors , again no change .
I also made sure that the wire is not running next to other wires. I could toy with the spacing or try and shield the wire .
I’m just wondering why I have this issue now , I’ve run VEMS in 3 other cars and never had it so I’m wondering what’s different .
Re: 1983 URQ Alpine White/Mocha 20VT / VEMS / EFR
Posted: Mon Oct 15, 2018 10:22 am
by audifreakjim
One other thing to try, maybe it's your plug wires. I always kept an old trusty set of stock wires around for troubleshooting. Maybe they are a little too noisy or something.
Re: 1983 URQ Alpine White/Mocha 20VT / VEMS / EFR
Posted: Mon Oct 15, 2018 11:35 am
by pilihp2
What kind of wiring harness are you running? Factory? your own custom? I had a ton of issues for a while with toomany pri triggers past like 3k RPM's at one point. I Replaced the shielded looms for the primary and secondary sensors all the way to the ecu and that resolved that issue for the most part.
Ground points are incredibly important too.
Where does the ECU ground to? where do the coils ground to?
EDIT: Please keep in mind, I just recently blew a motor from what I believe may have been trigger issues. Definitely a good idea to get these problems sorted sooner rather than later.
1983 URQ Alpine White/Mocha 20VT / VEMS / EFR
Posted: Mon Oct 15, 2018 2:07 pm
by Afterthought
The harness is one that Marc custom made for me so I would be more likely to suspect something I did, like how I hooked it up or grounded it .
The ignition ground is at the block (with my intake manifold I don’t have that factory location anymore) . Maybe I should try changing this .
The ECU is grounded in the car at the factory ground location for the ignition which is under the dash. Bare metal.
I will try and post a pic of the triggerlog. It doesn’t look like excess noise to me but I don’t know a lot about them .
Another option I can easily do is borescope inside the bellhousing and look at the ref. pins
Re: 1983 URQ Alpine White/Mocha 20VT / VEMS / EFR
Posted: Mon Oct 15, 2018 2:15 pm
by DE80q
I know your running VEMS, not MS like I am, but try adding a heavy ground cable from the block to the chassis, as well as the transmission to the chassis. This cleaned up guite a bit of odd issues I had with my setup.
Re: 1983 URQ Alpine White/Mocha 20VT / VEMS / EFR
Posted: Mon Oct 15, 2018 5:14 pm
by mr_aj_johnson
Afterthought wrote:
G28 is not new but I never hear of them failing (maybe they do?)
Can but rare. Like Jim said spacing can be an issue though noise or grounds are just as likely. Would be nice to see the log itself- make sure that the secondary trig isn't missing that cycle causing a too many pr trig errror. (been a while since I've played with vems but I think this can occur)
Re: 1983 URQ Alpine White/Mocha 20VT / VEMS / EFR
Posted: Mon Oct 15, 2018 5:20 pm
by alxdgr8
As I mentioned in a message, but I'll post here for reference too. Probably due to the 'small' reference pin on the 7A flywheel, you can weld on a larger one through the starter hole.
https://www.motorgeek.com/viewtopic.php?p=671478
https://www.s2forum.com/forum/technical ... heel-scope
http://www.theprojectpad.com/viewtopic.php?f=14&t=2423
Re: 1983 URQ Alpine White/Mocha 20VT / VEMS / EFR
Posted: Mon Oct 15, 2018 8:46 pm
by Afterthought
DE80q wrote:I know your running VEMS, not MS like I am, but try adding a heavy ground cable from the block to the chassis, as well as the transmission to the chassis. This cleaned up guite a bit of odd issues I had with my setup.
Man I got excited thinking maybe i forgot that ground but I popped the hood and its there. Body to the engine mount block and ties in with some other grounds.
I'm thinking about trying to move the ignition ground from the engine block to maybe a spot on the body, but the stock location would be block so I'm assuming there is a reason for that.
I may have to look at the pin like Alex mentioned.
Re: 1983 URQ Alpine White/Mocha 20VT / VEMS / EFR
Posted: Mon Oct 15, 2018 9:10 pm
by audifreakjim
So you are running Audi Trigger? I’m not a big fan of that, seems pretty prone to errors. Do you have an oscilloscope for your laptop you can use to make sure all of the pins and sensors are lined up? I was lost trying to get a car running on vems until I ordered one.
Re: 1983 URQ Alpine White/Mocha 20VT / VEMS / EFR
Posted: Tue Oct 16, 2018 11:19 am
by carl
I wouldn't move the coil grounds to body, old oem wires sounds like a good idea, shot in the dark but maybe lower ignition dwell a little.
If the sensor is aftermarket it could be giving you issues, I've tried one of those and the spikes were lower than oem on the scope, so pretty useless.
Like everybody else said, try getting them closer, pretty sure that's the problem.
Could also be some chipped tooth on your ringear.
I've had issues with hall signal window being too much at the edge, I'd get some random missed triggers due to belt slop. Doesn't seem to be your case but worth a look.
Another idea, unplug the alternator for a quick test, could be a noise source too.
Unlikely but have you talked to Marc about the reversed pins on sensor, just in case?
1983 URQ Alpine White/Mocha 20VT / VEMS / EFR
Posted: Tue Oct 16, 2018 8:42 pm
by Afterthought
audifreakjim wrote:So you are running Audi Trigger? I’m not a big fan of that, seems pretty prone to errors. Do you have an oscilloscope for your laptop you can use to make sure all of the pins and sensors are lined up? I was lost trying to get a car running on vems until I ordered one.
It’s Audi trigger yeah. I’ll have to look online and see what I can get . I see some oscilloscopes with probes that plug into USB.
carl wrote:I wouldn't move the coil grounds to body, old oem wires sounds like a good idea, shot in the dark but maybe lower ignition dwell a little.
If the sensor is aftermarket it could be giving you issues, I've tried one of those and the spikes were lower than oem on the scope, so pretty useless.
Like everybody else said, try getting them closer, pretty sure that's the problem.
Could also be some chipped tooth on your ringear.
I've had issues with hall signal window being too much at the edge, I'd get some random missed triggers due to belt slop. Doesn't seem to be your case but worth a look.
Another idea, unplug the alternator for a quick test, could be a noise source too.
Unlikely but have you talked to Marc about the reversed pins on sensor, just in case?
I have an LS engine in my shop with these same coils that I may be able to swap. I’ll look.
As far as moving the sensor closer to the pin. Since they both sit in that bracket , on the block they’re as close as they go , but I may be able to get creative with some sanding or something and reduce the thickness of that block . I’ll look at that. If I move them I’d have to verify that they are close but not hitting .
The Pins being swapped should be done internally to the harness but I can attempt to check .
Here’s the flywheel. I believe it’s stock on a 3B 200. Also says it can be used in RR.

If it is in fact the pin causing my issues I could consider modifying this piece to allow the sensor to sit closer to the pin.

Re: 1983 URQ Alpine White/Mocha 20VT / VEMS / EFR
Posted: Tue Oct 16, 2018 10:00 pm
by DE80q
From what I have read, it's not the distance of the sensor from the pin, but the diameter of the pin itself. I was sent an aluminum flywheel to repair once. The guy had attempted to weld a couple blobs onto the sides of the pin to make it wider, but ended up breaking the pin. I made a pin with a larger top and milled it to match the radious of the correct pin location. I haven't heard anything about if worked or not though. I'll try to find the pics I took of the "mega pin".
Re: 1983 URQ Alpine White/Mocha 20VT / VEMS / EFR
Posted: Wed Oct 17, 2018 12:06 pm
by varia
Sometimes a much bigger (ferrous) pin, and basically a zero distance wont fix it.
Few had luck with changing the firmware in vems....
Last resort a 60-2 on the rear
Re: 1983 URQ Alpine White/Mocha 20VT / VEMS / EFR
Posted: Wed Oct 17, 2018 8:26 pm
by 85oceanic
I hate dealing with trigger errors! I run the Audi trigger with VEMS in my 4k. I used to have severe issues with it at times and ultimately didn't get them fixed until I purchased a harness from EFI express along with switching out of the NGK to Bosch plugs. Before, I ran the NGKs with a modified URS4 engine harness to VEMS Econoseal.
Re: 1983 URQ Alpine White/Mocha 20VT / VEMS / EFR
Posted: Thu Oct 18, 2018 9:52 am
by Afterthought
varia wrote:
Last resort a 60-2 on the rear
I don’t have time to get and install a 60-2 [LOUDLY CRYING FACE][FACE WITH TEARS OF JOY]
85oceanic wrote:I hate dealing with trigger errors! I run the Audi trigger with VEMS in my 4k. I used to have severe issues with it at times and ultimately didn't get them fixed until I purchased a harness from EFI express along with switching out of the NGK to Bosch plugs. Before, I ran the NGKs with a modified URS4 engine harness to VEMS Econoseal.
Maybe I’ll change the plugs again . I have NGK , Bosch , and denso plugs I can try . Would be in interesting test to see if it makes any difference
Re: 1983 URQ Alpine White/Mocha 20VT / VEMS / EFR
Posted: Thu Oct 18, 2018 12:23 pm
by carl
Afterthought wrote: If I move them I’d have to verify that they are close but not hitting .
Yea, abit of playdoh and a cellophane cover or something similar less spongy, maybe clay, should do the trick. Cut off excess/sides with a razor and it should tell you your clearances you have to play with.
Ring gear looks good.
If you want to increase the tdc's pin magnetism effect you could always go through the starter hole and mig weld a blob at the back of the pin.
My experience with bosch triple plugs in the recent years has been terrible, they kept cracking, maybe they don't like solid lifters or are just made cheap now.