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Old 10-16-2007, 10:27 AM   #21
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still no dice. thoroughly confused this morning, since it started up INSTANTLY this morning with 38deg coolant temp and 43deg manifold temp. so once it got over the initial quick stumble and started idling, i shut it down quick before the temp rose more than a degree or two, and tried to fire it again. zilch. nothing.

messed with it for probably ten minutes and couldn't get it to do a damn thing. like i said, confused...

though, once i got into work i did remember that i may have cooked my ignitor when i was doing the install, burning MSQ files (file->open->burn) without unplugging the ignitor. at one point right after i finished the install i had no tach signal to the cluster, so i know it's at least been less than fully operation at one point. it's acted fine since, but i imagine that could POSSIBLY have something to do with my cold start issues?

i have a replacement and am going to swap it in when i get home from work tonite and cross my fingers. thoughts, anyone?
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Old 10-16-2007, 10:33 AM   #22
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It's VERY easy to flood the engine when working with cranking enrichments, and in the scenario you presented (successful start, quick shut down to try again) adds to that because you likely have heavy afterstart enrichments kicking in immediately after that first cold start-- if the engine is under those heavy ASE when you shut down the cylinders may end up pretty wet and then not want to restart even though your cranking PW may be fairly close.

It's likely a combination of slightly less ASE, and maybe slightly less cranking PW needed at that temp. Also- check the priming pulse-- what's it sending in there? That's adding to it too.

A heavily flooded engine with wet plugs can be VERY hard to start-- you pretty much have to pull the plugs, let the plugs and the cylinders dry out, and then start over. Been there, done that a few times.
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Old 10-16-2007, 10:40 AM   #23
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yeah, i have thought of that, actually. no idea how to tell if i'm giving TOO MUCH instead of too little.
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Old 10-16-2007, 10:43 AM   #24
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mine started right up this morning, i basically divided my PWs in half.

Im sure i flooded it yesterday. I was lucky it caught at all. i guess all the backfires helped clean out the system :gay:
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Old 10-16-2007, 10:47 AM   #25
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divided them in half, huh? yeah, i noticed the map i got from you was REALLY high at the colder temps when i compared it to the DIY settings. i figured longer on colder starts was better. lol.

see, my problem is when it's not starting, i don't get ANYTHING, no backfires, no hiccups, nothing.

i did take a look at the flood clear setting, and don't know if it's right or not. since i don't have a linear TPS, and that's listed as a "raw" value (which i assume means voltage?) where would that be if i want to be able to depress the gas pedal to crank it for a bit in flood clear mode, with no fuel?
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Old 10-16-2007, 10:53 AM   #26
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mine are:

7.1
6.7
5.4
4.4
3.5
2.9
2.3
1.9
1.5
1.3

with 460cc injectors.
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Old 10-16-2007, 11:03 AM   #27
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Without a linear TPS you can't use flood clear mode. And in my experience it's possible on some engines to flood them bad enough that this doesn't always 'clear' everything very well anyways. It helps blow out the cylinders some, but it won't dry the plugs and some plugs don't like to fire soaking wet very well.

On another note mentioned above, the trend should be longer cranking PW at colder temps. What you're trying to figure out is 'how long?'.

With the engine clear (not flooded) try cutting the CPW back 20% at that 40* point and see if it still fires reliably. If so then you probably had more fuel there than you needed and you can likely scale some of the surrounding CPW accordingly too (TEST!).

Make small adjustments, test between each change, and save off .msq files with descriptive names so you can go back to a 'known good' or 'known best so far' setup until you get it perfect for your setup...
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Old 10-16-2007, 11:06 AM   #28
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yeah, mine are a LOT higher than your new ones, brain, since what i've had were damn similar to the ones you sent me in that msq. i think i'm around 8.2 at 40* and like 5, 4, 3 etc... below that.

another thought that crossed my mind was whether the injector size comes into play here. commonly i thought that ALL one should need to change is req_fuel, but these are millisecond pulsewidth values. bigger injectors, smaller values?
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Old 10-16-2007, 11:08 AM   #29
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i thought the same, but that req_fuel doesnt come into play.

since my injector is 50% larger than stock and i was using DIYs vaules. I divided them in half. seems to work out perfectly. since my larger injector will squirt about the same fuel as the smaller one now in the same situation.
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Old 10-16-2007, 11:09 AM   #30
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Quote:
Originally Posted by devin mac View Post
another thought that crossed my mind was whether the injector size comes into play here. commonly i thought that ALL one should need to change is req_fuel, but these are millisecond pulsewidth values. bigger injectors, smaller values?
Read the mspnp manual, and you will find that it explicitly instructs you to modify cranking PW with injector change. Not only that, it shows you, mathematically, HOW to change them Good stuff, that DIY!
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Old 10-16-2007, 11:11 AM   #31
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how did i miss that... i need to start having my coffee BEFORE i try to start the car... though, without starting it, how do i get to Dunkin Donuts? ;-)
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Old 10-16-2007, 11:11 AM   #32
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Quote:
Originally Posted by Braineack View Post
i thought the same, but that req_fuel doesnt come into play.

since my injector is 50% larger than stock and i was using DIYs vaules. I divided them in half. seems to work out perfectly. since my larger injector will squirt about the same fuel as the smaller one now in the same situation.
Remember that PW includes injector open/close time, so you'll get better results if done according to DIY instructions (essentially subtract out open/close time, change to account for injector change ratio, add back open/close time, voila!)
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Old 10-16-2007, 11:12 AM   #33
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Good stuff, that DIY!
i'll second that, though. can't thank Jerry enough.
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Old 10-16-2007, 07:31 PM   #34
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stock 1.6 blue tops are 203CC, right?
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Old 10-16-2007, 09:34 PM   #35
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230cc I believe...
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Old 10-16-2007, 10:19 PM   #36
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Well, I two was experiencing the no restart problem....but mine is turning out to be a heat soaked AIT sensor and bad clt-related air density corrections.

after about 3 secs of the engine being cut i begin to heat soak. by the time im about to start the car the sensor is reading 100*. my density correction values were screwing it up somehow, im not even sure the are good now. but once (if) it cranks over it's incredibly lean.

MY cold start seems perfect now, so it's on to troubleshooting this. What seemed to work was using DIYs density corrections. I let it sit for a few mintues, verified a 100* intake temp and it started right up and was rich for a few seconds before it quickly dropped down to 70*. Hopefully some sort of heat sheilding or wrap will help....
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Old 10-16-2007, 11:00 PM   #37
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Quote:
Originally Posted by Braineack View Post
Well, I two was experiencing the no restart problem....but mine is turning out to be a heat soaked AIT sensor and bad clt-related air density corrections.

after about 3 secs of the engine being cut i begin to heat soak. by the time im about to start the car the sensor is reading 100*. my density correction values were screwing it up somehow, im not even sure the are good now. but once (if) it cranks over it's incredibly lean.

MY cold start seems perfect now, so it's on to troubleshooting this. What seemed to work was using DIYs density corrections. I let it sit for a few mintues, verified a 100* intake temp and it started right up and was rich for a few seconds before it quickly dropped down to 70*. Hopefully some sort of heat sheilding or wrap will help....
I never had a problem with IAT heat soak the whole time it was mounted in my plastic stock crossover tube. Now that I've got higher underhood temps with the turbo, and the IAT is mounted in a piece of steel, I get pretty bad IAT heat soak.

I wish there were startup-only IAT-based corrections.

-Mike
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Old 10-16-2007, 11:10 PM   #38
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Quote:
Originally Posted by grippgoat View Post
I wish there were startup-only IAT-based corrections.

-Mike
Isn't that what "Cranking Pulse Width Temps" (MAT Only) under Cranking Prime Table is for?
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Old 10-17-2007, 06:40 AM   #39
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Originally Posted by FoundSoul View Post
230cc I believe...
that's the 1.8 browntops 1.6 bluetops are 205cc
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Old 10-17-2007, 09:48 AM   #40
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Quote:
Originally Posted by grippgoat View Post
I never had a problem with IAT heat soak the whole time it was mounted in my plastic stock crossover tube. Now that I've got higher underhood temps with the turbo, and the IAT is mounted in a piece of steel, I get pretty bad IAT heat soak.

I wish there were startup-only IAT-based corrections.

-Mike

yeah, i dunno what the deal is now. even without heat soak it wont restart without tons of effort.

this morning i stopped by Rosenthal, intake temps of 50 coolant at 190. stopped for about 3 minutes and came back out. Tried to crank it and no go, all temps about the same as when I left it. :(
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