Board logo

Random/instantaneous flooding
Chaz - 4/7/21 at 08:11 AM

Hello!

I seem to have a problem with my MS2 setup (zetec, ITBs) and wondering has anyone had similar?

I have managed to get megasquirt up and running, started the autotune etc so all going well. After an unknown amount of time, sometimes 1 min sometimes 15 mins the injectors (definately 2 but possibly all 4) dump a mammoth amount of fuel in which immediately stalls the car. Fuel then spills out the ITBs (yes!) and begins to boil on the closed valve heads and in the cylinders. Once it set fire to the exhaust!

Anyone else had this? I think its an earthing issue, the problem is i dont know which earths i need to be checking? Inside the ECU or outside (wiring). The fact its intermittent and only when moving could mean wiring external to ECU.

Some help would be appreciated thank you!

[Edited on 4-7-21 by Chaz]


coyoteboy - 4/7/21 at 09:30 AM

Since it's repeatable, I'd be logging it to see what happens!

Never heard of this problem specifically but it could be a combo of a few things happening.


obfripper - 4/7/21 at 01:00 PM

I have had injectors locking open due to the u4 fet driver chip failing, however this was with an 2004 ms1 with the original MC34151 chip which has been superceded to a IXDI404 which is pretty reliable. The fault was also permanent, instantly flooding during the priming pulse before cranking at every ignition on.

Your situation sounds like it could be linked to an incorrect setting in tunerstudio triggering massive acceleration enrichment. It may be worth starting a new project in tunerstudio from scratch, using only your engine details to calculate req_fuel and fuel maps. You should be safe to export the current ignition map to the new project.

Dave


number-1 - 4/7/21 at 01:36 PM

It might be worth seeing if anyone else runs the same ECU and can send a base map to you. Just out of curiosity....What fuel pressure reg are you running at at what PSI? I had similar fuel spillage and it was the FPR running too high a pressure


Chaz - 4/7/21 at 05:44 PM

I think my fuel pressure is fine, static it’s about 3.3 bar but drops to 3 bar in dynamic flow. Thanks for the idea of someone running my tune but I doubt anyone would want to put this tune into their car!

I have checked acceleration enrichment but I actually have it turned off because of this. The other part of ‘acceleration’ enrichment is the VE table as I’m using the combo of TPS and MAP for ITB tune. I didn’t press the accelerator quickly as I want tuner studio loop to be able to learn before it stalls.

Yes I will try logging it, think I tried last time but didn’t spot anything unusual. Will try again


coyoteboy - 5/7/21 at 11:35 AM

Share your logs, I can take a little scout about too.