82streetracer

iTrader: (1)

Recently finished up a 6yr rebuild of my TII swapped FB. I had this issue with my old setup, and it is still there, so I think I know whats up, but wanted to bounce it off some of the more experienced builders here on the board.

Old setup:
S5 13bT block. 550/1600 injectors, haltech E6k, factory TII igntion coils and TII CAS.

New setup
Same S5 13bt block, same 550/1600 injectors (sec now have resistors), haltech SPrintRE, AEM/Mercruiser smart ignition coils, stock TII CAS. Whole car has brand new custom wiring harness, built from scratch/kit.

both setups car runs and Idles great. No drive-ability concerns.

When cranking/starting the car (esp when hot), it can sputter and sometimes pop through the exhaust. It sometimes alsobogs like its firing too early. The tach can bounce all over the place during cranking at times.

My current thought is that this may be a starter issue. The starter is very old/high milage, and will pop a 200amp breaker if cranked for more than 10-15 sec. Could an excessive starter draw cause this issue???? The starter is one of the few electrical items that came over from the original setup.

Just looking for some input before I drop $150 on a new one.

gxl90rx7

iTrader: (1)

ive noticed sometimes old starters and put noise on your trigger signals. set your trigger gain to zero, and try increasing your filter

i would replace the starter, get the automatic model, they are 2kw upgrade

82streetracer

iTrader: (1)

I have a JDM S5 13bt, with a USDM S4 TII Trans. Is there a specific year/model I should buy. 2kw is like 200amps on its own? That is super high.

82streetracer

iTrader: (1)

Got a new starter (cheap O'reillys) model. No longer blows breaker Cranking is smoother and quieter and tach is no longer all over on cranking.

But it does seam to kick back sometimes, like its firing way too early. I changed trigger and home filtering to 1 from 0. There is 2 and 3. It did seam to smooth starting, but it was also a mildly warm engine and not a cold-soak; which is when its been most prevalent.

What are the side effects of this filtering?

Where do i find trigger gain?

Thanks again for any input

gxl90rx7

iTrader: (1)

haltech told me the filter setting is really just setting the trigger voltage threshold. so if filter is too low, it will pick up noise spikes instead of actual trigger signal.

the trigger signals increase voltage with rpm, the best signal is at redline, and the worst most noisy signal is during cranking. the best setting would be filters set as high as possible, as long as its not missing triggers at idle and cranking

82streetracer

iTrader: (1)

This is still an issue. Seamed to improve initially after starter replacement, but yesterday it was real bad. If it matters; it has been noticeably colder here. And I noticed later that the tech bounced less during a hot start. I took a video. I'm starting to think this is a signal strength issue rather than a starter noise issue. Any suggestions?

gxl90rx7

iTrader: (1)

just asking the dumb questions.. assuming you have tried the higher filter settings, have you tried a different CAS?

also you say you are using a custom harness, does it have a shield around the CAS signals? make sure this shield is grounded at the ECU.

as far as cable routing, you do not want the shielded CAS cable running nearby and parallel with the spark plug wires, starter, or alternator wires.

it would not hurt to do an continuity/ohms check from the CAS connector all the way back to the ECU connector too. check each signal continuity to ground also (shouldnt be any)

Aaron Cake

iTrader: (1)

Where are you pulling 12V power for your ECU? Sometimes people take it from the starter lug. This is BAD. Noise city.

82streetracer

iTrader: (1)

ECM has dedicated power/ground direct to battery (fused) it also has a shared ground with the Wideband (which I understand is important for datalogging). Coils are also direct to battery.

Main vehicle power (main fuse block) does come off the starter Lug. I have a rear mount battery, and 2ga cable (+ and - ) going from the battery to the starter. Vehicle has multiple redundant grounds. This was how it was shown on the AA wiring kit I used.

I was looking into adding a capacitor or something to the starter circuit to cut the noise. I could reroute this back the battery, but the harness is all loomed and that would be a lot of work to redo that correctly.


I upped the filter setting to 3 and that helped a lot but it still is erratic from time to time. But the Tach is not flipping out nearly as much. I'm starting to think it needs a CAS, but this motor has maybe 50K on it (used JDM) and was in pristine condition when received. Are they known for issues like this? Seams like a simple electrical device that would have a low failure rate.

gxl90rx7

iTrader: (1)

sounds like you have ground problems.. any long ground cable run acts as antenna for EMI, especially if it is a return for spark current

I would ditch the long ground cable from the battery to the starter. Instead, ground the battery with a short 2GA cable straight to the chassis. then run a short 2GA cable from starter mounting bolt straight to the chassis. Ground your ECU with a short wire straight to the chassis. That should be all the grounding you need. any more may be causing ground loops and more potential sources for EMI

your IGN-1A coils have separate ground for signal and spark. The spark ground should be connected to the engine somewhere near the plugs, like the starter mounting bolt mentioned earlier. The signal ground should be grounded through your ECU harness or straight to chassis ground

also on your CAS, make sure you are using a metal cap and not one of those aftermarket see-through caps.. the metal caps help keep out interference

C. Ludwig

iTrader: (27)

No. No. And no.

Battery negative runs to the engine block. Not to the chassis. This ensures a clean primary return for the ignition. From the block run a short cable to the chassis for chassis ground. That's all you need. More connections just create ground loops which create all sorts of havoc. Make sure to remove paint from the engine and chassis connection points. We also use some conductive grease to minimize corrosion.

ECU ground should go directly to battery negative. This is the only true 0v source in the car. The battery also acts as a capacitor to dampen voltage spikes. This gives the ECU a clean power source and a bit of protection.

Pin B and C of the coils can both be grounded to the engine block. Each coil should ve grounded to the rotor housing it's discharging into. We use the threaded bosses on the top of rotor housings. Pin D must go to the battery negative post. Short cuts here ensure poor coil performance.

82streetracer

iTrader: (1)

I have the coils grounded as you described. They each have a heavy Bat(-) ground, a chassis ground and a respective rotor housing ground. I am going to remove the ground from the battery to the chassis, leaving my direct block and block to chassis ground and see if I get an improvement.

One other note: on rare occasion, the electric speedo becomes frozen, but always resets with a key cycle.

82streetracer

iTrader: (1)

I removed the engine to chassis ground, leaving the batt to chassis ground (due to much easier access) and this seamed to solve issue but only temporarily. After a couple of drives it almost seams to be worse. Is it that big of a deal to have engine to chassis vs batt to chassis? I'm trying to find a local CAS to try swapping it out, thats an expensive part for a test swap.

82streetracer

iTrader: (1)

It would seam that the Batt-to-chassis ground was not tight. It is difficult to access the body side of it. But I thought I could feel it moving around and so I pulled the bin to gain access. Sure enough it was not tight, which explains a lot of other minor issues I've been having (fuel pump fluctuation). I've had about 6 successfully smooth starts since. Only time will tell.