Help! CAN NOT START/eratic timing/rpm spikes during cranking

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58Ratt
MegaSquirt Newbie
Posts: 5
Joined: Fri Jun 09, 2006 6:39 pm

Help! CAN NOT START/eratic timing/rpm spikes during cranking

Post by 58Ratt »

msII, v3 board, MSD 6A w/probillet dist., VW 2017 turbo port inj, 397cc inj,

OK here i go....... started "tuning" a few days ago. The first day i played with the cranking pulse widths practically all day and i was getting a few blip here and the but that was it, the only way i could actually get it started was to put it in flood clear mode and turn the key. it would start, but it was missing, backfiring, and smoking bad. The only way to keep it huffing and puffing was feather the throttle. I was also getting tons on kickback and stalling.

so i started looking for other things that may be wrong, and the next day i grabbed the timing light.....now, i had locked out my MSD billet distributor to 0* and when i got the timing light on there my timing was all over the place,anywhere between 10* and 60*. So i swapped my VR wire from the dist. and re-routed my power and ground wires as far away as possible.(although my pos. VR wire is still pretty close to the MS POWER). timing did get better, it was at a solid 55* BTDC(although i caught a few erratic sparks) so i went back and set the offset in the trigger wizard.

now it was closer to starting, but still, when in flood clear mode is the closest it comes to starting.

just checked my logs and there are spikes in the 4800rpm range. i am planning on playing with the 2 VR pots tomorrow, i suspect false triggering.

what constitutes a safe distance from noisy power wires?

i don't know where to go with my cranking pulse widths. they started as 12ms at -40 and 4ms at 160. i suspected i was flooding the motor so i took the numbers down and started working my way back up with no luck.

what are other 2litre engines running for this field?

please help, i have very little direction for tommorow!

here is the URL to my log file. the starts after the first three, are all in flood clear mode.

http://www.filelodge.com/files/room38/1 ... SDfix3.xls

thanks,
chris
Last edited by 58Ratt on Mon Aug 14, 2006 8:58 pm, edited 1 time in total.
PSIG
Experienced Squirter
Posts: 201
Joined: Fri Jun 11, 2004 11:02 pm
Location: Poulsbo, WA

Post by PSIG »

58Ratt, perhaps you can post your .msq - but you're getting large variations in pulse width and enrichment. Try turning your Acceleration Enrichments off (set the threshhold real high like 50 for TPSdot or 200 for MAPdot) to see if that helps. We need more info...

David
58Ratt
MegaSquirt Newbie
Posts: 5
Joined: Fri Jun 09, 2006 6:39 pm

check this out....new datalogs and .msq

Post by 58Ratt »

ok, so i got back to it today. first thing, i grabbed the timing light and set the timing to about 10*btdc using the timing wizard. as i was doing this i was catching random blips at 20* 60* etc just like before but not as consistantly.
so i decided to cut the MS power wires out and reroute them as far away as possible from the VR wires and the MSD white wire. I then turned the r52 pot clockwise about 3 turns.

then i went into MT and turned my pulse widths to 7.3 at -40 and 1.7 at 160, and ASE to 15%
Then like david suggested, i went to accel enrichments and adjusted TPSdot to like 75%

the result: had the closest starting attemp to date the first time i turned the key, but after that it seemed like i was back to where i started but this time putting the ECU into flood clear would not start the car(must be close to correct pulse width for cranking). however i now noticed something new. as i was cranking i could hear what i believe was the FP relay turning on and off, and after watching the rpm i noticed it was spiking from 0 to 600ish to 0 and then back up, over and over.

let me know what you think. i read something about this awhile ago. i will continue to search.

check out my msq and logs:
PSIG
Experienced Squirter
Posts: 201
Joined: Fri Jun 11, 2004 11:02 pm
Location: Poulsbo, WA

Post by PSIG »

The fuel pump pulsing on and off means a configuration error. That could explain a lot but I haven't seen these specific electrical traits personally - so I'll default to someone who has. I don't want to keep you hanging but would rather you get a specific answer than a good guess or wild goose chase. :?

David
58Ratt
MegaSquirt Newbie
Posts: 5
Joined: Fri Jun 09, 2006 6:39 pm

Post by 58Ratt »

so i have been researching for the past 4 hours and found that, after inverting my VR wires from the probillet i was suppose to change some ignition settings......INPUT CAPTURE to FALLING EDGE and SPARK OUTPUT to GOING HIGH.

i also completely spaced on the "max spark duration" it was still set to 3 ms or something stupid like that.
58Ratt
MegaSquirt Newbie
Posts: 5
Joined: Fri Jun 09, 2006 6:39 pm

Post by 58Ratt »

yup that was it!!!! cleared it right up! even got it running and idling.
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