Pulswidth spiking, i r confused

Buddyworm · Post by **Buddyworm** » Mon Jun 23, 2008 10:18 am

Earlier this week a friend and I went out and fiddled around datalogging in with my CA. (Didn't have a wideband yet so that's absent.) Anyway, we did a 4th gear pull from a 50km/h roll and I'm getting injector pulswidths that spike and/or don't match up with the cells the ECU is accessing in the fuel table.

I'm unable to discern any cause-effect relationship for the spiking as there doesn't seem to be any corresponding change with any of the other sensors.

Also, my pulsewidths are a helluva lot shorter under higher load than what's on the fuel tables, yet the engine feels like it's running great.

Would it still be running in closed loop down lower? But even then the O2 sensor doesn't budge from 0.3volts.

Any ideas?

Thanks,
Kenji

kenbam · Post by **kenbam** » Mon Jun 23, 2008 11:52 am

Pulsewidth spikes are probably just load enrichment, dont want any flat spots under acceleration.

Actual pulsewidths will never match exactly whats on the fuel tables. Fuel table settings are simply a starting point, ecu then looks at a myriad of other inputs and then TRIMS the base settings to end up with actual pulsewidths. Engine temp, air flow (which includes air density changes through air temps) and so on.

I would advise getting a wide band asap.

Buddyworm · Post by **Buddyworm** » Mon Jun 23, 2008 12:13 pm

Yep, I'm now in possession of an Innovate LC-1 so tomorrow we shall see the real goings on.

Matt · Post by **Matt** » Mon Jun 23, 2008 1:09 pm

Try using the S13_CA18_256_E_fix.adr file in the misc directory and see if this fixes the injection reporting guage at all.

Earlier boards had the wrong memory address programmed in the board, so we put together this address file to enable an override with the correct injection (verified by measurement on the scope)

Buddyworm · Post by **Buddyworm** » Wed Jun 25, 2008 10:18 am

Well the pulsewidth spiking I was seeing seems to be normal behaviour. Though I may have mitigated it somewhat by replacing the FPR vac line that may have begun to leak. At any rate my AFR's are looking good. I had no idea the stock maps were so conservative though, 9.5 to 10:1 AFR's at the top end? Good grief, that's piles of room for improvement.

I'm pumped to get started.