First start up using megasquirt.. 1992 5.0.

Blucifer99

I only understand every 3rd word
Jul 15, 2018
466
35
38
Port Mcnicoll Ontario
Hey guys. Im having a hard time gettin my base timing set . the funny thing is that i can get megasquirt to match up with my timing set to fixed timing at 20° and it reads 20° on the balancer.. But when i switch back to use table its running at 16°.. I kno my dizzy is set to 10°.. So im tryin to figure out why its idling at 16° and 850rpm.. Shouldnt it be at 12° and 850rpm? Should i make my trigger angle offset lower then 10.00? Cause i kno the lower i go the balancer and tunerstudio doesnt match up with the 20° i set in fixed timing mode.. This is the base tune that came with the megasquirt.. Also when i fire up my car. It idles up to 3000rpm and drops down to 850.. I honestly think im missing something or doing something wrong. So if anyone can chime in about this. That would be awesome..
Another thing i just noticed is that my injector squirts per cycle is 4.. Shouldnt it be 2? Most basemaps ive seen that are for the 5.0 mustang is 2 squirts per cycle..
 
Last edited:
  • Sponsors (?)


It is going to idle at whatever number you have set in the timing table. If there is 16 on the table it will idle at that number, the timing offset is already taken into account in the table values.
 
It is going to idle at whatever number you have set in the timing table. If there is 16 on the table it will idle at that number, the timing offset is already taken into account in the table values.

Also another thing is when i fire up my car. It starts and revs up to 3000rpm for a few seconds and then drops down to 850... Any idea why the base tune on the megasquirt would do that? I havnt done anything to my tables. All i did was calibrate sensors and add my injector size and timing thats it
 
The idle settings have to be tuned. It's a base tune, not a runs perfectly on the first turn of the key tune. It's only meant to get you started. If you need a crash course I have tuning videos in my signature. I also do tuning classes and services.
 
  • Like
Reactions: 1 user
The idle settings have to be tuned. It's a base tune, not a runs perfectly on the first turn of the key tune. It's only meant to get you started. If you need a crash course I have tuning videos in my signature. I also do tuning classes and services.

Ok ill fire up my laptop and post my tune file. I really havnt touched anything besides the calibration and fuel amd timing so everything is still all the same. But ill post it in a few mins
 
Ok ill fire up my laptop and post my tune file. I really havnt touched anything besides the calibration and fuel amd timing so everything is still all the same. But ill post it in a few mins


heres my current tune for my car.. also id like to know more about your tuning classes that you do... id like to soak up as much information on tuning as i can before i do my engine build... basically its the reason i got the megasquirt.. i live too far from the nearest dyno shop lol so im doing it all myself
 

Attachments

  • CurrentTune.msq
    115.8 KB · Views: 427
I sent you a PM with the details.

well ive got the timing matching the 20* on megasquirt and it idles just fine... the only thing i cant figure out is why it revs up to 3k right after the engine starts... it hangs there for like 3-5 seconds then drops to 850... Now is it the idle cranking duty setting that controls engine idle on start up? cause ive noticed that all the fields in the idle cranking duty startup are all set to 25.1.. because the engine does the same if its at operating temp or cold.. this is really the only boggle ive got lol. cause there really isnt any info on fast idle on start up info on any of the sites..
 
Ok lets talk Idle settings for a minute...
The Cranking/Duty Steps is the position the Idle valve is going to move to as soon as the engine begins to turn over, so 25 = 25% open.. Now this runs on a curve with engine temperature, the car will need more air cold and less hot. the idea is to get the car to start and be just above target RPM then settle in to the correct idle.
Warmup/Duty steps this is the position the valve moves to after the initial crank to run taper time wears off.. [this is found in the idle settings] lets say the valve says to move to 15% full warm 200* engine temp and you start the car, the valve will go first to the cranking position then slowly move to the run position.

Now the idle valve is not the only thing that affects idle, timing plays a huge role in how a car will idle... too much timing and the car will have a hanging idle, or the idle will fall very slowly / surge.
There is a fine line when it comes to setting the idle up correctly for all conditions, and dont be upset when the idle is perfect hot but acts up when cold, the cold idle settings can only be tuned once a day, so they take awhile to get right.
AFR plays a large role in how well a car idles as well, leaner typically makes for a more aggressive idle with a chop. but the other way and go too rich and the idle is sluggish and boggy, this also causes the plugs to foul.

The Closed loop idle settings are too many for me too outline in text, that why i made videos about them.
 
Ok lets talk Idle settings for a minute...
The Cranking/Duty Steps is the position the Idle valve is going to move to as soon as the engine begins to turn over, so 25 = 25% open.. Now this runs on a curve with engine temperature, the car will need more air cold and less hot. the idea is to get the car to start and be just above target RPM then settle in to the correct idle.
Warmup/Duty steps this is the position the valve moves to after the initial crank to run taper time wears off.. [this is found in the idle settings] lets say the valve says to move to 15% full warm 200* engine temp and you start the car, the valve will go first to the cranking position then slowly move to the run position.

Now the idle valve is not the only thing that affects idle, timing plays a huge role in how a car will idle... too much timing and the car will have a hanging idle, or the idle will fall very slowly / surge.
There is a fine line when it comes to setting the idle up correctly for all conditions, and dont be upset when the idle is perfect hot but acts up when cold, the cold idle settings can only be tuned once a day, so they take awhile to get right.
AFR plays a large role in how well a car idles as well, leaner typically makes for a more aggressive idle with a chop. but the other way and go too rich and the idle is sluggish and boggy, this also causes the plugs to foul.

The Closed loop idle settings are too many for me too outline in text, that why i made videos about them.

Well i know my timing "mechanically" is set at 10° and thru the megasquirt its spot on 20° when i fix the timing table.. So hopefully thats not the cause... As for startup. It just revs high for literally 3 seconds then drops down to 850.. No choppy idle and no surge. It actually sounds like it should.. Its not boggy either when its running. Throttle is responsive actually really nice as a matter of fact.. And as for my afr. Im stuck with my narrowbands until my aem gauge gets here and i wire that up so i can make sure my afrs arnt the cause.. But it doesnt smell rich at all. Maybe a tiny hint of rich but then again it is -15 where im at in canada so that could be from the coolant temp/fuel mixture set up in the basetune in the ecu.. I honestly dont understand why a apparent "basetune" would cause my car to shoot up in idle.. My stock ecu when used never did that.. Not even now it starts normal as can be.. I just hope something isnt wrong with the car that i cant figure out..but my personal thought is something is set to high on the startup side of megasquirt
 
Well i know my timing "mechanically" is set at 10° and thru the megasquirt its spot on 20° when i fix the timing table.. So hopefully thats not the cause... As for startup. It just revs high for literally 3 seconds then drops down to 850.. No choppy idle and no surge. It actually sounds like it should.. Its not boggy either when its running. Throttle is responsive actually really nice as a matter of fact.. And as for my afr. Im stuck with my narrowbands until my aem gauge gets here and i wire that up so i can make sure my afrs arnt the cause.. But it doesnt smell rich at all. Maybe a tiny hint of rich but then again it is -15 where im at in canada so that could be from the coolant temp/fuel mixture set up in the basetune in the ecu.. I honestly dont understand why a apparent "basetune" would cause my car to shoot up in idle.. My stock ecu when used never did that.. Not even now it starts normal as can be.. I just hope something isnt wrong with the car that i cant figure out..but my personal thought is something is set to high on the startup side of megasquirt
Thats whay im telling you man you have to tune the idle settings, the base tune is meant to get the car started for the first time so you can make adjustments, thats all its going to do. If you want a base tune setup specifically for your application I can provide one but its not free and it wont act exactly like you want it too the first time, thats the nature of a base tune, its only to get you started.


Now if you want to fix the high starting RPM I can help with that, but i will need a datalog of the event and I need to know which megasquirt ecu you are running.
 
Thats whay im telling you man you have to tune the idle settings, the base tune is meant to get the car started for the first time so you can make adjustments, thats all its going to do. If you want a base tune setup specifically for your application I can provide one but its not free and it wont act exactly like you want it too the first time, thats the nature of a base tune, its only to get you started.


Now if you want to fix the high starting RPM I can help with that, but i will need a datalog of the event and I need to know which megasquirt ecu you are running.

Well to say the least. Im not askin for anything for free. Nothing in this world is free. Not even air.. And as for a basetune. I can work with the one i have in the megasquirt thats in my car.. And as for a datalog. Id have no problem sending you one once im near my car.. I just dont like the idea of a cold start shooting to 3k rpm. That :poo: does damage. So like i said im not lookin for a free handout. Im more looking for a kick in the ass in the right direction before i totally mess up my engine because of a high idle on a cold motor.. I understand it needs to be fine tuned.. I just need that idle to settle down because as of right now i dont wanna even start my car to do any tuning
 
I think you really just need a good understanding of the software, once you know what each setting does its much easier to make an informed decision about what to do. Im an instructor so i have learned to explain things in laymans terms so that its easy to understand. You would be amazed at how much you learn in an hour with the right help.
 
wel i may have figured out why the dam car starts at 3000rpm and settles down to 850... the idle control is set to inverted.. so at 25.1 would actually be 75% open.. and its allowing way to much air on startup. atleast thats my theroy.. when it warms up abit this weekend im gonna figure this crap out on my own i guess.. cause after spending 10gs on my motor.. i gotta save up to be able to take any tuning classes.. Gotta eat first apparently lol
 
Thats why I asked what MS ecu you were running. All the MS2PNP v3.57 boards the iac wiring is inverted, so your theory is correct if thats the case. Now that also means your warm idle valve position is probably wide open which explains why you have the idle advance set to remove timing based on RPM. Likely you are forcing the idle down by retarding the timing, check to see if your headers are glowing at idle, if they are your timing is extremely retarded at idle.

You dont have to use my paid services to get my advice, but in order to give you proper advice i need the pertinent information.
 
Thats why I asked what MS ecu you were running. All the MS2PNP v3.57 boards the iac wiring is inverted, so your theory is correct if thats the case. Now that also means your warm idle valve position is probably wide open which explains why you have the idle advance set to remove timing based on RPM. Likely you are forcing the idle down by retarding the timing, check to see if your headers are glowing at idle, if they are your timing is extremely retarded at idle.

You dont have to use my paid services to get my advice, but in order to give you proper advice i need the pertinent information.

ok well im running the Ms2pnp and the version i belive is 3.3.1v my ecu was made in october of this year if that helps.. if that doesnt sound right let me kno where i can find the version/firmware version number your asking about.. and sorry for the tardy response,, my work takes me away from the computer alot cause theres no signal up in the bush lol