MX5Ireland

Got this the other day to try and solve a problem, which it didnt so back up for grabs!

PWO, with leads, want what I paid, €40.

Call me on 086 8463532

Tim

Wanna expand on the problem?? Maybe we can help

J

When the car comes on boost it dies, its like its hitting a limiter at around 5k.

Drives fine when the boost dialled down to around .5bar, but any higher and it hits this dam wall!

Changed plugs, fuel pump, coil and no change.

Have you changed the plug gap? Mine used to blow out the spark above 8psi until I regapped them.
I've just put in new plugs recommended by Frank, NGK ZFR7F-11 I think, they are slightly longer, they made a big difference.

See here

Which ECU are you using?

Think they were Denso ones, the guy mapping it gapped and fitted them, which made no difference.

He thought it might have been the tps, but Ive been told that it isnt that, as its not needed at all, and some dont even bother using one.

Played around with the boost, and if i dial it down to .4/.5 bar it runs fine, and revs the whole way through, but once I go any higher it hits this dam wall!

Really confused about this...Bit of a pain, as I just want the car finished!

Still great fun at low boost all the same.

And im running a megesquirt pnp

What size injectors have you? Can you datalog and see what your injector % usage is when in boost? You just might be running out of head room or something.
whats your overboost protection set to?

Ive 550cc and a walbro 255 so im not running out of juice!

NOt overboost preotection either!

Whats your REQ_FUEL set to?
Have you a WBO2 sensor?

Steve wrote:Whats your REQ_FUEL set to?
Have you a WBO2 sensor?

Think its 5.6

And Im running an lc-1

If I back off it will rev through, but not on wot.

And as I said, with the boost lowered, it will rev through most of the time.

When its set to .8bar It was spinning up forth in the wet as it was coming on power......It will be fun when its right!!

sounds about right actually with 550s?

Steve wrote:sounds about right actually with 550s?

Yeah so I'm really confused about this! Quite annoying, as it's so close to being finished!!

what is the LC-1 saying when it does this?
Any smoke? (possible you have too much fuel? 550s are big enough)

The airfuel isn't changing when it happens, stays the same, around 12 or so. Going to change the fuel pressure regulator and see if that helps.

Just checking... if not fuelling... Max boost limit cut?

Nah Ive checked the overboost and it aint that..