James1436215376

Fixed it (seems to be OK) used contact cleaner on the igniter plugs and cam position sensor.

Ive a question or two about the LS# coils, Ive read on an AEM (gasp!) board that the later LS2 coils are 12v+ triggered not -ve triggered, is there any susbstance to this or can I go ahead and wire up the coils I have as per the link LS1 coil pinout picture? Heres the quote: "the truck coils will work...as long as they're the ls1-style.... The LS2 coils are different from the ls1's. Ls1's need a ground to trigger whereas the ls2's need voltage. The truck coils are supposed to provide a little hotter spark than the vette/f-body coils anyhow" and link: http://forum.aempower.com/forum/index.php?topic=21558.msg119628 Here are the coil part numbers: AC DELCO # D514A STANDARD # UF414 GM # 12573190 Cheers

Ive got a mercedes DOHC M119 5 litre V8 being run by a LinkPlus G1, Im having issues with really bad missing under all conditions, i.e both load and cruise and yeaterday while taking the car for a spin I started to drop 4 cylinders, F#CK!. The wires are arcing a little bit but always have, the coils are relatively new HEC 715's, I also have a new 4 channel igniter. I was playing around a few weeks ago with the dwell changing from 3.5 to 5ms as I found that the coil buildup was no where near saturation point, I didnt want to reach saturation because I dont need it to but I wanted to see if more juice would net me any results, didnt notice anything but since thn I started to have a little bit of a miss at around 4500-5000 RPM at speed, dwell has been put back to 3.5ms. I havent changed fuelling and spark or any other parameters, there is no water in the plug bores and the wire surpressors are OK. Have I stuffed the igniter eg. too much current or are the coils stuffed (checked resistance both are close to each other but I dont have the coil specs) Sorry for the rant but Im scratching my head here and will soon push the car off a cliff. Cheers for any help.

Thanks Simon, is there more value in running sequential with a G3 LinkPlus?

My engine is wired to run the injectors in sequential mode but it was tuned to run group, no real reason given by the tuner i.e. any issues with sequential vs group. The car will run in sequential with a noticable difference in power delivery on my but dyno. However there is issues with acceleration under medium to high load, there is a miss present at around 1500rpm. Also after the car is at operating temp I will come to a stop at the lights or whatever and the revs will stumble and drop to below 500 and if I dont take action the car will stall. Is this just a factor of fine tuning the idle values for inj and spark as well or are there other fundamental tune differences between group and sequential. Cheers

Thanks Simon ill give it a go.

Only ever happens after the car has just been started (cold). Ill start muck about for a few seconds then after Ive backed out and shift to neutral the revs will flare then drop and stall. Any pointers to possible causes in settings etc. Running Link Plus G1. Cheers

Just wondering, while monitoring the ignition I notice that the ecu always puts the ignition back to static timing (9degrees) mainly in the 2nd row from 750rpm to 2250rpm, even just a few minutes down the road from getting underway and even to a ignition cell with 24degrees? I havent pushed the engine to see if Im getting knock events under high load I cant see a point for doing so. So Im wondering if RFI can influence the signal or if the engine is striking something in the engine bay as its quite tight in there with a DOHC 5litre V8, BTW the fuelling/ignition in those zones has not changed since it was initially tuned just over a year ago. The HT leads are standard Beru Mercedes parts with suppresors in the plug ends, spark plugs are NGK BCP6ES (youre not supposed to use resistor plugs with these wires), I have changed the coils to HEC715's but the originals were low ohm as well but maybe these are a cause? The engine is standard N/A with 10:1 comp and I always run 98octane gas. At the end of a 20min deive I would have over 200 knock events recorded whilst only have driven the car normally as in not exceeding 3000rpm or putting it through high load. Can anyone help, the car is booked in at the dyno on the 29th but opinions would be appreciated.

sorry yeah LC1 is what I meant.

Thanks Ashley, my o2 sensor bit the bullet a while ago so im opting for an LM1 wideband + controller so I can tune that part of the table and have better Lamda mode running. Thanks for the help.

Thanks, I realise that the idle is hard to get perfect or close to with the G1. Ive fiddled with the fuel in the row to the left of where the car idles at and increased it to within 5 points of the idle cell, the idle cell is 115 and the box left of it in the 250rpm column was at 90 so now 110. To the right of the idle cell Ive matched the fueling to 115. Ignition wise the idle cell is at 9 and the cell on either side of it is also 9, should I increase these cells a few points and see where it gets me?

Thanks Ashley, so do you have any ideas as to why the engine will drop to such low revs when I lift of the throttle, this mainly only happens when your free revving the engine but the revs still go quite low i.e. dip below 500rpm if I lift off aburptly while the car is at speed regardless of engine temp. My MAP @ idle (op. temp) is a steady 30kpa, fuel clamp is 26kpa and overrun is 33kpa, I observe when I rev the engine to induce the problem that MAP only drops to ~40-45kpa at around when it stalls. When the link was tuned the value of the overrun was 20kpa but the probelm was still evident back then, I changed the overrun value after reading through the manual myself - the displayed overrun value is when the fuel cut is deactivated? i.e below this value fuel is supplied to enable idle should I have the oerrun around 40-45kpa? Theres no help in the linkplus manual that tells you how to setup the fuel cut overrun like there is for the fuel clamp value. Sorry about the 20 questions. Thanks again.

I tried emailing on monday and havent recieved any reply, id this upgrade no longer done?

Ive got the fuel cut option on, but I cant find (if there is even one)the fuel cut activation table to set the RPM level. The problem is when I rev the engine to anything above 3000rpm and then close the throttle, the revs will drop right down past the set idle rpm and the engine will stall. If the G1 LinkPlus doesnt have the activatoin table do I have to disable the fuel cut option to fix the problem, thus negating economy while at cruise and with a closed throttle???

Problem solved, added a battery back in factory position and got a 115amp (from 80)alternator to look after them.