I'm assuming you've exhausted most of the culprits for these problems already. But... What series PTU are you running atm? Hows your wiring loom? While running rough, have you tried wiggling any of the wires near all your connectors to try to either induce/fix rough idle? Have you tried cleaning your AFM Hotwire? I haven't ever had to look at one before, but as an experiment, last weekend i pulled mine off for the hell of it, ripped the engine side mesh off and cleaned the hot wire with a damp cotton wool ear bud. It surprisingly made my idle & reving smoother! So maybe something to try too.
Is this still going on? Mate hit up a dyno and check your AFR's. You may have a fuel pressure problem due to a bung regulator or an aftermarket chip in there that's overfuelling. Especially on a cold start where the ecu is adding extra fuel to get the ol girl going in the morning, if your fuel pressure is too high or your fuel map is wrong, then on a cold start you'll be very close to flooding.
Yeah but this issue developed on its own with no mods or changes to induce the change in AFR, unless like you say regulator. Can I test the regulator some how? It does run rich, you can see it on my last dyno, but that was before the problem started and I havn't notice any more black smole than then.
Yeah as you can see in my post below the TPS seemed to fix it temporarily and now it's back, not as bad as before the PP though. S1 PTU but the problem is months old now I would have expected it to die complety. S2 is next on my list.
This may not be relevant, but I thought it might help anyway. I discovered that the neutral switch was disconnected on my Zed (due to it originally being an auto a few owners ago). With my CAS Timing on 15deg, it was a bit sluggish and liked stalling when shifting from 3rd to 2nd. Anyway, adjusting the CAS timing to 25deg fixes that issue - a big thanks to zed4life for that one! Its now more responsive and doesn't stall
Are you sure that's what he did? Mark, can you elaborate on this please? Moving base idle timing from 15 degrees to 25 degrees doesn't sound like something that Mark would do...?? It actually sounds more like it may have been fixed possibly via neutral switch to let the ECU know when it's in gear which would then make idle at 25 degrees while in gear??
Not something he did, something he suggested. If the ECU thinks the car is in gear, it advances the timing by 10 degrees. If you don't have a neutral switch, the car always thinks its in gear and runs 10 degrees advanced. So, if your timing is set to 15 degrees and you don't have a neutral switch, its actually 10 degrees retarded (think about this for a second). So you need to set it to 25... Make sense? The other alternative is to rewire a neutral switch, but there's no real benefit doing so. Datascan tells you if you have a neutral switch or not.
Hey Mark, From my understanding of the whole Auto trans neutral switch is that it only works while in CTP, so when car is in gear but at idle, the timing is at 25 degrees instead of 15 (like in park - or same as a manual at idle) ... but while auto shifter is set to any gear other than park/neutral, as soon as you go out of CTP, the timing goes from 25 degrees back to the normal timing curve for the rest of the rev range. I've experienced these timing figures by having both auto and manual tunes in my ecu at different times. So from what i understand, if you actually physically advance the CAS from 15 degrees to 25 degrees, you're fixing the (in gear) idle timing side of things, but in doing so, making the rest of the timing curve advanced by 10 degrees throughout the entire rev range. The other thing is that Datascan doesn't tell you what your CAS timing is actually set at - only what timing is set within your particular ECU tune. Am I reading into this correctly or have I misunderstood?
I have noticed looking at mine(a/t) while in gear timing is set to 25deg, if the rpm is raised the timing will continue to advance through out the rev range. It does not seem to fall off once out of ctp. Datascan or any other will only show the commanded timing not the actual timing. If the cas is set to 17deg base, the ecu is unaware of this so still shows the timing value it has calculated where as the actual timing would be 2deg advanced. To get work out the actual advance you need to subtract your cas timing from the ecu calculated timing. Then add this figure to 15.
whats correct? The neutral switch idea or what I mentioned, vaccume, CAS, PTU and TPS? My neutral switch is only about 12months old (new from Coz)and works perfectly. Revs go up about 150-200rpm when in gear.
Cleaned my AFM hotwire the other day with Contact cleaner and OH MY GOD what a difference. The car is smoother, at idle and driving, definately worth doing, MattB
