Help- 2TGEU stuttering/backfiring on brand new Haltech

[king-szeitszam]

Hi everyone.

Hoping someone can help me out with this problem before I lose my mind. For those of you who aren't familiar with the story, my TA22 has been off the road for six months for a 2TG engine swap and complete EFI install including sequential ignition. I've been screwed over left right and center by installers who had no idea what they were doing, but I finally managed to drive the car home today after paying my $7000 for all the work done.

No sooner than had I driven 10 minutes down the road and stopped at a set of lights did my problems start. First, the car failed to pull away when I tried to accelerate out of the lights- the feeling was similar to a carburettor spluttering when the car is stalling. I whacked her into second gear and gave her a bit of a kick in the bum to get her going- before I knew it she was stuttering and leaping all over the place- power on, power off, power on, power off very rapidly. Imagine tapping the accelerator on and off as fast as you can and you get and idea of the feeling. Then the car starting backfiring- not just little burbles but full on BANGS- enough to scare me, and I've heard more than my fair share of explosions. I thought I'd busted a hole in the head or something but the noise came from the exhaust.

By this point I'm rolling down a hill- car stuttering at random and losing power, I take the turn to my street and the car just dies on me. Zip, zap, zoom- gone. Revs to 0, electronics off, no indicators, no lights- dead. I roll the car to the side of the road thinking she was fried- turned the key again and she sputtered to life through some miracle- again the sound was like a carburettor trying to start cold and without enough fuel.

Now whenever she's under heavy load she starts sputtering and skipping and backfiring- it feels like I'm riding a bronco or some shit. I've got no f***king idea what's wrong with it- it's literally a 30 minute old install.
I called the installer and he said it could be the ECU plugs coming loose- but I double checked them and they seem tight- besides if it was that why am I only experience symptoms under heavy load?

Anyway, if anyone's experienced this before feel free to throw ideas at me, as I'm thoroughly over things going wrong.


Little info about the car:

2TGEU
Haltech Sprint 500 ECU
Four AEM smart coils, sequential ignition triggered by hall effect sensor and 36-1 chopper wheel
Lumpy exhaust cam

Cheers,
Frank

[allencr]

Revs to 0, electronics off, no indicators, no lights- dead.

Start at the battery.

[king-szeitszam]

Start at the battery.

Ignition off, ignition on- everything's there. Starts first time.

[king-szeitszam]

Took it for a diagnostic drive. Symptoms are as follow. Cold started car- idle was 500rpm if that- ran like a carby that needed the choke pulled out. Reversed it down the driveway (steep hill) stalled on the slope, had to roll it down and start on the flat again. Idle remained at 500rpm for 10 minutes before finally picking up to closer to 1000.
One thing I've managed to deduce is that the issues are consistent which I guess may make them easier to fix or find the source of. Car has issues accelerating out of 1st and 2nd gear, it seems like the engine is starving and there's not enough fuel getting in- similar to when a mechanical fuel pump isn't delivering the flow you need and you try to go full throttle and the car just sort of farts along.
Other consistent problem is stuttering/skipping/jumping in 4th and 5th. This has got me stumped as it could be so many things. Does it when the engine is both hot and cold, around the same speeds too (80km/hr for 4th and 70km/hr for 5th)- usually only occurs at 35% throttle or more (most frequently when going up a gradual hill).
Engine also seems to me misfiring regularly when just cruising in 5th on the flat (5-10% throttle)- can be heard in the exhaust note, goes from a humming 'voooom' to a vibrating 'voomvoomvoomvoom'.

The car will also now stall or very nearly stall after running it hard. (4k RPM and above then putting clutch in immediately).

This sound familiar to anyone? Lean spikes caused by ignition misfire.. thus injector duty ramping down due to decreased load? Base timing problem? Delayed enrichment problem? Asynchronous enrichment problem? I have no idea!

Hope someone can help.

[Dan_k36]

Have you had a taco installed or played around with coil grounds? Sounds like that
How are your coils wired up? I saw you had issues with one before hand

[allencr]

Ignition off, ignition on- everything's there. Starts first time.

WTF does that mean?
//
If it stops running, the tach drops to zero, everything electrical shuts off - dead indicator lights, then there is a major current interruption and whether it is intermittent or not, starting at the battery & working towards the ECU, fuel & ignition systems is the only way to find out what's doing it. Especially on a car that has been F'd over by a lot of hands.
//
You can wiggle all the plugs you wanna. Good luck.

[king-szeitszam]

Have you had a taco installed or played around with coil grounds? Sounds like that
How are your coils wired up? I saw you had issues with one before hand

Hi Dan,
Not played with anything like that to my knowledge no. There was an issue with the ones before hand and I still am not sure why there was an issue there- the installer has only speculated and not really given me any solid information regarding that. Coils are mounted on a bracket on the LHS strut tower and should be grounded perfectly. They are the so called 'smart coils' with inbuilt igniters and are controlled directly by the ECU which is given its trigger input references by the trigger wheels in the dizzy and crank.

Allencr- while I appreciate you taking the time to reply, there is no need to be rude. I was on the side of the road when I responded to you so my answer was brief.
When the engine stopped simply all I did was roll the car to the side of the road and turn off the ignition, then kick her over again and she started perfectly- like she'd just stalled or something.
As stated in my latest post, I took the car for a diagnostic drive and experienced none of the electrical issues, nor anything to indicate there was a current interruption intermittent or otherwise.

That said, if I had all the answers I wouldn't be on here asking for help- so I could be mistaken in my diagnosis and have missed something. I'm simply trying to get as much information as I can on the table- for both my reference in the shop next week and for anyone reading this.
The recurring issues are as per my latest post- so far after four drives the phantom electrical issue seems to have been a standalone occurrence and hasn't happened again.


Edit: I'm looking at the trigger wheel and pickup to see if that may be the issue- I'm going to adjust the clearance the pickup has from the wheel to see if that makes any difference. Current gap is 5mm, but I may take it down to 2mm.

Frank

[andrew_mx83]

Trigger wheel gap should be around 1mm or under?

I know f all about aftermarket efi but i would be checking ALL the earths by the sound of that. Battery, engine, body, ecu, sensors, fuel pump etc. Also the wires to the trigger wheel pickup need to be shielded, and the shield itself must be grounded (at one end only)


On the coil wiring note when i converted my car to waste spark i had issues with 'cross firing', although all the coil wiring was heat shrinked it all needed a second layer of heat shrink otherwise it would try to fire one coil and actually fire 2 or 3 together. Simply by separating the insulated wires to each coil it would stop misbehaving.
-it must be pulling some serious current through the 12v side of the coils.

[caam]

Yes get your trigger sensor closer and go through all of your grounds.
But $7000 wtf! Take it back get it fixed and name and shame! Too many professional fuckwits - I feel your pain

Cam

[king-szeitszam]

Trigger wheel gap should be around 1mm or under?

I know f all about aftermarket efi but i would be checking ALL the earths by the sound of that. Battery, engine, body, ecu, sensors, fuel pump etc. Also the wires to the trigger wheel pickup need to be shielded, and the shield itself must be grounded (at one end only)
On the coil wiring note when i converted my car to waste spark i had issues with 'cross firing', although all the coil wiring was heat shrinked it all needed a second layer of heat shrink otherwise it would try to fire one coil and actually fire 2 or 3 together. Simply by separating the insulated wires to each coil it would stop misbehaving.
-it must be pulling some serious current through the 12v side of the coils.

Awesome reply thanks for that. DIYautotune says maximum 5mm so I think the installer had gone the max- but now that I've looked at it I agree that it's way too far. The car is going back to the shop tomorrow (hopefully) for a check over. I'll mention all the earths and the shielding when I'm there. As far as I know there's definitely no shielding on the trigger pickup leads. The same with the coil wires. What's something good to use to heat shield it?

Cam- Yeah man I'm thoroughly sick of this shit. The reasons I forked out the dosh was because I didn't have the time to do it myself- but 7 months and 7k later I'm realising it would have been faster to do it myself, even if I was only doing an hour or two a week.
The problem I have now is that the installer is saying "well it ran fine when we did the road test". And he's right- it did. This was what prompted him to suggest the ECU wiring had come loose and to check how well they're seated.

Keep flinging suggestions my way, I'm taking note and I'm going to drop it all on the installers desk tomorrow with a big 'WTF MAN'.

[king-szeitszam]

Cold started her again- idled so low that the exhaust sounded more like a fart than the confident rumble of a 2TG. Twisted the idle screw on the ITB's a quarter turn for a temporary fix there.
Short drive after warming her up revealed that she's still skipping- exhaust starts getting choppy and intake noise starts skipping too at the same time, loses a bunch of power then picks up again, then drops off again and starts skipping all over again.

Also- weird thing; adjusted the spacing of the sensor to 1mm- she wouldn't start! Just turned over- no ignition. Put it back to where it was, tah dah- ignition. Why would how far away the sensor is matter?

[lilcrash]

Do you still have the capability to run a stock distributor ignition? I've installed a few ecus over the years and there is no way that is $7000 worth, did they fully rebuild your engine,gearbox, diff, give you a brake upgrade and give the car a respray for that price.

[king-szeitszam]

Do you still have the capability to run a stock distributor ignition? I've installed a few ecus over the years and there is no way that is $7000 worth, did they fully rebuild your engine,gearbox, diff, give you a brake upgrade and give the car a respray for that price.

Not without getting a new dizzy. I sort of shot myself in the foot with this one, the 4 teeth inside the dizzy that trigger the VR sensor have been ground off leaving just one to give a home signal.

Yeah I agree it's a rip off- but it was as it always goes with these projects- more and more shit just keeps popping up and causing problems.
The money included an engine swap, ITB's, injectors, coils (2 sets of those since one set busted), all the running gear, new ECU, complete wiring for the ECU and ignition system, all the plumbing done again, 2 new pumps, surge tank, new idler arm, bushes, brake repair and the rest was dyno time and labour time. The last two is where they really kick you in the nuts- 150 per hour on the dyno and 100 per hour general labour.

[lilcrash]

Looks like you need to find more useful friends. Be lucky if all that cost me more then $2500. And that allows $1200 for an ecu.

See if you can borrow a dizzy and test again. I'm pretty sure they just saw you as a young tool and bent you over.

I've got a 2t dizzy cant remember if it will fit though.

[king-szeitszam]

Looks like you need to find more useful friends. Be lucky if all that cost me more then $2500. And that allows $1200 for an ecu.

See if you can borrow a dizzy and test again. I'm pretty sure they just saw you as a young tool and bent you over.

I've hit up Anthony for a hand so hopefully we can have a gander at it sometime in the coming week- lots of things still not working such as the radio and most of the interior lights and the central locking.
I bought the ECU, ITB's, coils, injectors and most of the running gear myself to save money- even then it was still over $3000. The ITB's and ECU alone were $2100. Add ~$400 for coils and you've hit $2500 already..money gets you nowhere these days
Man hours and dyno time are universally ridiculous, and $150 an hour for the dyno was one of the cheapest I came across in my area. You're right in saying it's daylight robbery but I don't think they'd be kind enough to limit their greed to purely the younger generations, they hadn't even met me for the first two weeks of the three week project as I was busy and my old man took the reigns for that time, for all they knew they were dealing with a 65 year old VW mechanic.