(T) mpi sei ecu problem? / remap time? / Virgin Ecu?

Well, got 99% of the sei's problems sorted now - just one major one to contend with, which is the flat spot (Some of you may have read about this in my other thread) which has cropped up at 3.5k.

Normally mpi's don't seem to have this issue...

Anyway, it rears its ugly head most noticeably @ 60mph in 5th @ 3.5k.
Does show in other gears at other speeds but this is where it's really a problem (think country lanes etc...).

Got Alan (my mechanic) at woodcocks Fiat, in hull, to take a drive in her and have a poke around to see if he could determine what was going on, and we came to two conclusions (which in fairness I'd already concidered - but it confirmed my suspicions).

#1 - Duff ecu: Not really a common fault as such with the mk2 Seis, but a possibility all the same.

#2 - Ecu original map not suited to my driving style: Again, not likely, as she seems to be under-fueling at that rev range at that speed - And with the ecu having a (if somewhat limited) learning function, I would have thought the problem would have only been temperary. Obviously can be looked into further with a remap...

What I'm wondering is what's a better plan of attack?
Remap the existing ecu vs buying a virgin ecu, and with a virgin unit would I be able to keep my existing keys etc...

Anyone got any idea of cost on either option? (bearing in mind I'm based in Hull, and would prefer to to travel too far for remapping).
Anyone else suffering similar symptoms?

Just use 4th if your on the twisties


Remap is about the £200 mark from GSR. So use that as a rough idea.

I am sure this isn't an ECU issue so i think a virgin ECU will leave you out of pocket.

Looking on ebay a 59F virgin ECU is about £120, lot cheaper than dealer. There was a 4AF ecu on there the other day, but it's gone now and I can't remember the price. Probably similar though.

//edit - there is a 4AF ecu for a panda on there, will probaly work. £145. Just depends what ecu is in your engine bay.

Kristian

I can't see this as being ECU related.

As for driving styles, the car was designed by Italians, built by Poles........

No ECU warning light? Always suspect the crank sensor or the wiring..........

Ah yes the crank sensor.... twas suggested to me previously... will investigate 1st before I start ripping the ecu out

The crank sensor may be rpm related but you'd have that problem in all gears at said rpm, not just 5th gear.


Kristian

But he does have it in all gears -- I guess because he drives slowly he just finds it more often in top at 60 on country lanes.

Could be the wiring is chaffed, too, showing up only under a particular harmonic.

Or Knock sensor?

cheeky - but yeah it's in all gears, but most noticeable @ 60 in fifth.

main example would be slow motorway traffic or round here there are some dual carriageway sections set at 60.
Twistys get done in 3rd and 4th, but on the straights on the back lanes 5th is useful...

Wiring all seems good - infact the whole car is almost there, it's just sooooo annoying about this flat spot!

ok so, crank sensor and knock sensor.... where did I put my haynes...

Engine transplant and aftermarket ECU

It's MPI, isn't it. So, Haynes fine for crank sensor, but not for knock (not fitted to SPI).

The knock sensor is on the back of the block, so inacessible that I believed that MPI Seis didn't have them until me and Aaron found one on Emma's old engine. I doubt the knock sensor has gone, but if the wiring has been disturbed......... off to garage now so can tell you the colour of the wires.

forgive my ignorance / inexperience, but where does the crank sensor live on the mpi engine?

its the thing that point at the tooted wheel, near where your oil filter is

excellent

ALso, the knock sensor is on the back of the block, beneath the plastic air intake, sitting in the middle of cylinders 2+3, between the starter and alternator.

It's held on by one bolt, and has a two wire plug. Sure the knock triggers the EM warning light though, so prob not a problem.

KRistian

Mines a little lumpy up to 3k and then up to 5.5k, max horses or not some times. Half or full throttle at 3.5k, then off the gas pedal produces a major judder now and then so I think it's just a program thing on the MF59's on MPI Seicento's.

For what it's worth, there are two wires from the knock sensor, as Kripit says, 1 blue, 1 brown. They connect to the big black multipin connector (which I think has the injector cables, too).

Never noticed any hesitation/misfire on my MPI Sei............