Jump to content

Welcome to the brand new 205GTIDrivers.com website! We hope you'll enjoy it! Read the full notice here.

Sign in to follow this  
Rob Turbo

New Megasquirt Problem!

Recommended Posts

Rob Turbo

I've been making progress with the mapping but I'm now stuck at 4k rpm, it just doesn't want to rev over it, or even up to it sometimes, it just starts popping and banging, I adjusted the VR pot before, which was stopping me reving over 3k rpm, but then the rev counter was bouncing all over when it got to about 2800 rpm, now the revs stay about where they were but it won't go over 4k, could it still be the VR pot? If so, is there any way to set it properly, without having to hold my foot on the accelerator while I turn the screw slightly?

 

How big is the "sweet spot" on the vr pot? 1/4 turn, 1/2 turn, or less?

 

Also is there any way of setting the knock sensor circuit without making the engine knock? The knock light comes on around 3-3.5k rpm, just flashes for a second then goes off, I'm sure it's not a real knock, so I let it idle and turned the spark advance up around idle until the engine started knocking (then quickly turned it back down!!) but the light didn't come on once, so basically at the minute my knock sensor is useless :)

 

On the plus side, I got up a bit earlier this morning and tackled the cold start cranking, starts much better, still not perfect but it will do for now, also made a slight adjustment to the warm up enrichment but you don't get much time to play with that!

Share this post


Link to post
Share on other sites
Rob Turbo

Ok, after a lot of driving up and down a back road with the top off the ecu I've fine tuned the vr pots and can now rev freely!

 

So, just the knock sensor to tune now!!

Share this post


Link to post
Share on other sites
M@tt

nice work rob!! you'll have it nailed in no time!!

Share this post


Link to post
Share on other sites
madspikes

Sounds like your making good progress. Its a good feeling once you get the car running on the MS.

 

Once I got the basic map, every time I drove the car I had the data logger on and made mental notes of any issues so they could fixed later.

 

I miss driving my pug. :)

Share this post


Link to post
Share on other sites
Rob Turbo

Well the fuel table is about set, all the way up to 6000 rpm and 15psi boost, it's all still slightly on the rich side of ideal but I'm not aiming for 100% perfect just yet, I have a set of saab turbo injectors to fit at the weekend, apparently changing the req fuel value will keep my table somewhere near but will need tuning again, so there's no point doing it perfect twice!!

 

I also think I need another very slight adjustment on the vr pot, there's a bit of a splutter and pop at around 5500 rpm and all of my other pops and splutters have been vr pot related and changing tables around where the problem is hasn't made any difference, so out with the screw driver again.

 

Most of the time I'm out I've got it logging as well, it's just on my way to and from work that I don't have the laptop with me. MegaLogViewer is a great help, it's no good at adjusting the table for me but it puts everything I need to know right in front of me so I can work out what needs doing.

 

Does anyone have a spark table they could send me, preferably from a boosted xu engine, just so I can see roughly what I'm aiming for, an n/a xu would be a start even, at the minute the whole table is around 8-10 degrees advance, which I'm guessing isn't exactly ideal ;)

 

Thanks,

Rob

Share this post


Link to post
Share on other sites
Sign in to follow this  

×