MSefi.com read only forum (Jan.15,2018)

I recently have been having issues keeping my 16v VW running on MS-II... I've been using the system for over 2 years now with no issues thus far...

Before I get into everything, all engine timing marks line up and engine will start, but will not stay running...

Symptoms:

Engine will start fine, but immediately peg rich (9.0:1 on my wideband) and simply dies...I can keep the pedal pinned in clear flood mode but it does not seem to help...
I have reloaded my *working* tune countless times but to no avail...I am leaning towards a stuck open injector for three reasons...
1) After turning the engine off after starting it, my AFR will hoover around 10:1 for about 30 min before it returns to AIR...
2) On a datalog of the starting, my inj pw is around 17ms and duty cycle is around 5% (a good datalog shows pw should be around 8ms cranking and 50% duty cycle)
3) Before she shut down on me, my idle was beginning to hunt and the engine was bogging down while leaving stop lights (AFRs were ever so slightly getting richer as the problem got worse) (gas mileage also went from 28mpg to 19mpg in a matter of days, no change to the tune)

I have attached a log of the problem. Does anyone have any insight? I can't really perform the injector flow test b/c of the way the harness is routed in the engine bay...I am going to throw another set of injectors on it on Wednesday night to see if that helps...Any insight/help would be greatly appreciated.

I am also aware that I can test residual fuel pressure after key up to look for a drop in fuel pressure to see that I do in fact have a leaky injector but I do not have a FP tester at my apt and cannot perform the test...

TIA!
-Jayson

bd,

About #2 - the log shows what MegaSquirt is commanding the injector to do, it is NOT measuring what it is actually doing. So if you are getting 17 millisecond cranking pulse widths instead of 8 milliseconds, either the code is corrupt or something is your settings is causing this, not a stuck injector.

Looking at your log, though, reveals the answer. You cranking pulse width is just 0.3 milliseconds (not 17 msec) because your TPS is nearly 100%. You should only have have you foot on the gas pedal while cranking if you are trying to clear a flood condition. So that's the first thing to fix. Then work on the cranking pulse widths: http://www.megamanual.com/ms2/tune.htm#crank

The 17 millisecond pulse widths you are seeing is because of the afterstart enrichment adding to the normal pulse width. If you need to reduce this fuel, work on lowering the afterstart enrichments.

Lance.

Lance,

The reason for the TPS near 100% was because I had already started the engine a few time before and the only way to get it started is in clear flood mode...I have had no issues getting the car started and running over the past 2 years...

I have not touched the tune in the past 6 months as it has been running great...the pw I am getting is NOT normal and none of my settings have changed...is it possible for the code to become corrupt just like that?

bd,

I haven't had a single instance of corrupt code in several years of running megasquirt, but I change my code often (for testing) and have always had good serial comms. Those that have had comms issues seem to have a better chance of corrupting the code (the values burnt from the tuning software get written to the wrong spot in memory). Since it's free and easy, reloading the code is the first thing I would try, if this was mine.

Lance.

Lance,

Rewriting the code did not help...engine is still pig rich, but it's now 300 miles away so I won't be dealing with it for another couple of weeks. Thanks for all your help and insight tho.

-Jayson