sc400 Rev cut a 3750 RPM HELP URGENT

[Buttocks]

I've tried everything i can think of, anyone know of any genius's aroung Qld??

[madmont]

There was a suggestion that the speed sensor wire from the speedo to the ecu was picking up interference from another source possibly the tacho wire going to the instruments. You could try cutting the wire from the speedo close to the ecu and see if that makes a difference. You can always reattach if necessary. Does your cruise control work properly?

[sideshow]

bring car to sunshine coast around nov 10 to 14th and i can look at it for you

let me know will cost abit thou

i have had my snap on scanner talk to my 1uz its does sort fo ok job lets u see main things

but most of the time i use a multimeter for testing

did the scanners show much data

[wa5]

As I asked before. is it possible that the speedo has been flicked (odometer mileage turned back) as most jap cars have a 180 km speed limiter and any damage to the speedo may be interprated by the ecu as an attempt to bypass the speed limiter..(not being an expert on these things) I believe that the ecu goes into a safety mode when it 'senses' that the speed limiter is being bypassed and wont let the engine rev any harder than it would at 180 in top .

Perhaps one of our Northern Territory members can tell me what revs an SC400 is doing at 180 in top (my guess is somewhere around 3800)

Does the SC400 have a transmission position inicator in the dash? If so are all the lights for all the positions working? If not perhaps the ECU cant tell what gear the car is in. (which may also bring in the speed cut)

[Buttocks]

I've had this car on 2 different Diag units and one was a snap-on so i can't imagine that doing much good.
As for the car been wound back or played with i'd say 100 percent not.

[NeoNasty]

I guess.

Fuel pump controller computer. Fairly common problem I believe.

check out soarercentral.com for more info. Read through the forums.

[Buttocks]

Done that already

[Vios-GT_07]

erm..

edit : sorry u've already done that

i did mention coil packs.. so did u get to check that? could be one of the packs are fucked and can't support spark up till certain revs.. best to get it out and bench-tested.. i know a place that can do it but it's in VIctoria though..

[Buttocks]

I have also done that

[Vios-GT_07]

my u're in a pickle...

sorry i can't help much

but did you check fueling as well? i know u did the pump, but fuel filter, fuel lines, injectors?

yea i see why you need the diagnostic tool as well.. it's a bitch coz u've pretty much done everything i can think off..

anyway.. jsut to recap.. here's a checklist

spark plugs regapped and correct heat range
coil packs bench tested
ignitor bench tested
ECU bench tested
Injectors flow tested
fuel lines
fuel filter
fuel pump
AFM
Throttle cable??
TPS??

and with electronics
Speed sensor
Rev cut
Knock sensor
ingition timing check (what's the max ignition timing and is that right for the rev cut?)

anyone else got anything to add?

[thechuckster]

you forgot:
remove all electrics & looms, check, re-install starting with engine & gearbox.

or

park at any westfield shopping centre, leave keys in ignition and a window down, use insurance payout to purchase another car?

[gianttomato]

3750 is a wacky rpm to be cutting out. 3750 x 2 = 7500. Is that the rev cut for a 1UZ??

Could the ECU be "double counting" the ignition signal for whatever reason? Maybe check your earthing and make sure the coil plugs aren't loose.

[Vios-GT_07]

erm.. it's 7000 rpms for the 1UZ.. pretty sure...

and if the whole car is stock, it'd be a long shot if the ignition signals are scrwewd up.. but didn't he mention that he's checked all the coils and ignitors?

earthing is a good point... but if it's completely stock it'd be a hard one to find..

[thechuckster]

7000 might be a soft cut - buttock's description is a hard cut.

Something is either wired up wrong or has the wrong kind of sensor - perhaps this was the reason it was exported/sold in the first place (undiagnosable fault)?

[CrUZida]

1UZ hard cut is 6500 afaik.

I've hit it once and it sure didn't feel like a soft cut.