Xtreme Posted January 25 Report Share Posted January 25 Hi all, I have just installed a MonsoonX to a freshly rebuilt 4age 16V smallport with large 284/278 cams, standard intake, standard distributor & igniter setup and have been unsuccessfully trying for a week to get it running. The engine started and ran fine (wouldn't idle because of the new cams) before I stripped out the original ECU and installed the MonsoonX. I am running the built in MAP sensor and not the original 4age one. The engine keeps kicking and wanting to fire up but just won't run. I got it running last night once with a heap of throttle but can't get that happening today. For some reason the rpm keeps jumping between about 180 and 0 on PCLink and I can't work out why it won't sit stable. I have checked the timing with a timing light (needed 15deg trigger offset), changed the trigger offset by 360deg which did not help. Can someone please have a look at these files and see if there is anything obvious that I have done wrong? Thanks 4age base map new.pclx Trigger Scope - 2024-01-20 4;18;30 pm.llgx PC Datalog - 2024-01-25 6;21;03 pm.llgx Quote Link to comment Share on other sites More sharing options...
Adamw Posted January 25 Report Share Posted January 25 You have a trigger issue. The RPM will drop to zero whenever the ecu has lost position. Your trigger scope hasnt captured the problem as it looks like you clicked capture before crank so it just shows a stationary engine. Since your RPM drops to zero about once every distributor revolution, my guess is the ecu is not seeing trigger 2. Try dropping your trig 2 arming thresholds to match the pic below, if that doesnt result in more signs of life then do us a new trigger scope, making sure you only click capture when the engine is cranking. Quote Link to comment Share on other sites More sharing options...
Xtreme Posted January 25 Author Report Share Posted January 25 Hi Adam, thanks for such a quick response. I just tried that trigger setting but unfortunately it didn't help. Hopefully this trigger scope works: Trigger Scope - 2024-01-25 8;05;47 pm.llgx Quote Link to comment Share on other sites More sharing options...
Adamw Posted January 25 Report Share Posted January 25 It is actually trigger 1 signal that is sometimes not reaching its threshold. Its already set to the lowest possible value so not much more you can do from an ecu point of view. Most likely you will be able to solve it by reducing the trigger 1 sensor air gap, Im pretty sure most of the 4AGE distributors have an adjustable pickup in them. Set it to 0.2mm with a feeler gauge. Quote Link to comment Share on other sites More sharing options...
Xtreme Posted January 25 Author Report Share Posted January 25 It is adjustable, I closed the gap yesterday to 0.4mm to get it to trigger but I'll set it to 0.2 and try that Quote Link to comment Share on other sites More sharing options...
Xtreme Posted January 25 Author Report Share Posted January 25 You're a legend, that got it running! It fires up straight away but won't idle at all. I assume it's because I'm running a MAP sensor with large cams? Have you got any tips on settings I can try to get it to idle before I take it to get dyno tuned? Quote Link to comment Share on other sites More sharing options...
Adamw Posted January 25 Report Share Posted January 25 No I wouldnt think MAP for load would be any concern in this case. More likely just a lack of air or fuel. Check the base timing again with the engine running. Adjust master fuel or fuel table values around the idle area so that the lambda is around 0.9 (too rich is usually much less fussy than too lean). I have enabled idle ignition in your map attached below which will help. Assuming you dont have an idle valve, you will also need to adjust the throttle stop when warm so that it idles near target idle speed with the idle ign bouncing around its target. 4age base map new + idle ign.pclx Quote Link to comment Share on other sites More sharing options...
Xtreme Posted January 29 Author Report Share Posted January 29 Hi Adam, After not touching the vehicle for a couple of days I went to start it and it is back to kicking buy not firing up. Is there anything you can see in this trigger scope or base map that could be c ausing the issues? Trigger Scope - 2024-01-29 5;25;24 pm.llgx4age base map + idle ign.pclx Quote Link to comment Share on other sites More sharing options...
essb00 Posted January 29 Report Share Posted January 29 You're having some noise spikes on Trig2 - enough voltage to be armed & considered as a tooth. Increase the arming for Trig2 500rpm to 0.3V Quote Link to comment Share on other sites More sharing options...
Adamw Posted January 29 Report Share Posted January 29 I will have to bounce this off the firmware guys tomorrow. I can see it is resetting or not happy about the signal about half a revolution after sync but I dont see an obvious reason why. However I dont know all of the criteria that is being tested on every tooth in this mode to narrow down what is not being met. It is possibly too advanced and a little kickback is extending the elapsed time between 2 teeth. As a quick test in the meantime, can you temporarily set ignition mode to off and do another scope and cranking log like that. Quote Link to comment Share on other sites More sharing options...
Xtreme Posted January 29 Author Report Share Posted January 29 Hi Adam, I can do that but it'll be after work tomorrow as it's late at night here now. I'll upload once done. Thanks for looking into it Quote Link to comment Share on other sites More sharing options...
Xtreme Posted January 30 Author Report Share Posted January 30 Here is the latest trigger scope (with ignition mode set to off) and a cranking log cranking log.llgxTrigger Scope - 2024-01-30 4;50;32 pm.llgx Quote Link to comment Share on other sites More sharing options...
Xtreme Posted January 30 Author Report Share Posted January 30 Here is another trigger log with the trigger sensor gaps adjusted again Trigger Scope - 2024-01-30 6;15;13 pm.llgx Quote Link to comment Share on other sites More sharing options...
Adamw Posted January 30 Report Share Posted January 30 In the cranking log and trigger scope with ignition mode off everything looks good, in the 2nd scope it is back to resetting again - was ign mode back on for that 2nd scope? If it was then it possibly is just kicking back due to incorrect timing. Does it sound like it kicks back about once every two revolutions? Quote Link to comment Share on other sites More sharing options...
Xtreme Posted January 30 Author Report Share Posted January 30 Ignition mode was back on in the 2nd trigger scope. It sounds like it is trying to fire but it just won't keep running. It doesn't sound like it is kicking back but I'll check the timing again. I'll also check to make sure fuel is getting through all the injectors Quote Link to comment Share on other sites More sharing options...
Xtreme Posted January 31 Author Report Share Posted January 31 I just fiddled with the timing and now it starts reliably, revs fine and idles with the TPS screw adjusted in a fair bit. Thanks Adam! Quote Link to comment Share on other sites More sharing options...
essb00 Posted January 31 Report Share Posted January 31 Have you verified the trigger offset? Quote Link to comment Share on other sites More sharing options...
Xtreme Posted January 31 Author Report Share Posted January 31 I had the trigger offset 180deg out Quote Link to comment Share on other sites More sharing options...
essb00 Posted January 31 Report Share Posted January 31 10 hours ago, Xtreme said: I had the trigger offset 180deg out That's quite unusual, but can be because of the way you have aligned the driven gear in reference to the rotor position when dizzy was pulled out and put back in. Normally close to 0° or close to 360° (depending if you used G2 or G1 for Trig2). Quote Link to comment Share on other sites More sharing options...
Xtreme Posted January 31 Author Report Share Posted January 31 My distributor rotor (and tooth for the trigger) was pointing at the other trigger sensor at TDC for the cyl1 plug lead. The one I've wired up is 180deg out in the distributor. Advancing the offset 180deg was the only thing that got it it fire and run Quote Link to comment Share on other sites More sharing options...
essb00 Posted January 31 Report Share Posted January 31 Your engine is on a dizzy, so at 0/180/360/540 it should fire. That you say 180° pickup (from #1 TDC) on the dizzy is G1 --- and that is actually approx. 360° crank angle offset. Did you actually verify the trigger offset using a timing light and the trigger offset calibration page? Later on, you'll need the correct trigget offset for proper sequential injection and setting up fuel trims, ignition trims, knock control, etc. Quote Link to comment Share on other sites More sharing options...
Adamw Posted January 31 Report Share Posted January 31 I was just typing a similar reply to essb00 when he replied but will leave it here as further confirmation anyway. With a distributor the coil fires every 180deg, the rotor sends the spark to the correct cylinder, so it will still start and run with the offset out -180/+180/360/etc. The only thing that will be wrong with the offset out by 180 is the injection timing which usually makes very little difference to start up. It just sounds like the spark timing was either too advanced causing the kickback, or too retarded causing the spark to jump to the wrong post in the distributor. Quote Link to comment Share on other sites More sharing options...
Xtreme Posted January 31 Author Report Share Posted January 31 So you think I should try again with an offset closer to 0 or 360? I have been using a timing light for every trigger setting I tried. I can set it close to 0 and put the timing light on and see what happens? Quote Link to comment Share on other sites More sharing options...
Adamw Posted February 1 Report Share Posted February 1 What you can do to confirm the offset is giving the ecu the correct TDC is temporarily enable Individual cyl ignition trims in single mode. With the engine idling and a timing light connected to cyl 1, then put 10deg in the cyl 1 cell (0 in all others), if you see the timing mark move 10deg when you do that then the offset is correct. If you dont see the timing mark move then change the offset by +180 or -180 and try again. Quote Link to comment Share on other sites More sharing options...
Xtreme Posted February 1 Author Report Share Posted February 1 Well I don't know what's going on.. I went out to start it up to check the timing and it is back to not firing. I can't even get the timing light to work on a plug lead (it intermittently picks up a signal on the coil lead but not a spark plug lead). Is there anything in this trigger scope that stands out? Trigger Scope - 2024-02-1 6;25;58 pm.llgx Quote Link to comment Share on other sites More sharing options...
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