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The mkiv Supra Owners Club

SAFC, big injectors and startup


eyefi

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aye it is, we where trying to solve a boost issue but never got chance cos the bloody thing would not start. in the short time we had we swapped out the FPR and monitored pressure, checked & cleaned plugs and all that was fine. we were gonna have another look when he had got his new pressure tank on.

 

i'll swap the o2 and see what it does. its strange that the car started not starting immediately after injectors, pump, SAFC and FPR. and it really is a bastard to get started.

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I've got 650's on my car, (although I'm using the E-manage, the principle is the same), I have no start-up issues at all. It barely needs much adjustment to get it to idle properly (about -8% get's me an AFR of around 14.7). On a cold start, the AFR drops to about 10.5 for around 2 minutes, but that's never caused me a problem.

 

However... Before we did the single conversion, I new I had an inlet air leak. This played havoc with idle and cold start. I had to back the E-manage off by about 25% and cold starts were unreadable on my AFR guage, but I knew it was stupidly rich due to the black smoke it would produce at idle.

Obviously the stock ECU was trying to hard to compensate. :conf:

 

Might be worth checking the inlet for leaks. Mine was a poor screw thread/fitting of an external pressure sensor, and leaky trac removal kit.

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Originally posted by eyefi

its strange that the car started not starting immediately after injectors, pump, SAFC and FPR. and it really is a bastard to get started.

 

mine started playing up after the injectors were changed. I knew the air leak was there, but it had not caused me any real problems before.

 

Once the plugs get fouled up, especially after a few continous cold starts, it's PITA to restart. :(

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Guest Terry S

Eyefi the narrow band will be trying to bring the AFR to stoich. If it's fubar then it can't, where as the stock 440's should be almost there on the map. The SAFC only starts at 1000rpm from memory so can't affect the idle. You could raise the idle to 1100 and see what happens.

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its running rich, the plugs where brown after only a few hundered miles. it started ok after cleaning no1 plug, but that was probably just coincidence.

 

nah, didnt get to check AFR, no bung and im not sure how to get a good reading up the tail pipe (so to speak). looking at my wideband info it doesnt look like a very accurate reading can be acheived from the tail pipe, the further in the better.

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Guest Terry S

to get a decent reading you need to be 500mm up the tail pipe.

 

Do you understand what I am saying about the narrow band mate?

 

BTW how did the aeromotive go?

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Originally posted by Terry S

Eyefi the narrow band will be trying to bring the AFR to stoich. If it's fubar then it can't, where as the stock 440's should be almost there on the map.

 

so the o2 is trying to adjust before the engine fires?

 

Originally posted by Terry S

The SAFC only starts at 1000rpm from memory so can't affect the idle. You could raise the idle to 1100 and see what happens.

 

yeah, it does. while cranking and watching the adjustment value in monitor mode it is adjusting the fueling by what is set at the 1krpm point. so i thought it actually used this value while cranking, it would make sense. my powerFC has bloody loads of settings for cranking fuel adjustments, i'd expected the SAFC to have something for cranking, but i could'nt find anything.

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Originally posted by Terry S

BTW how did the aeromotive go?

 

still not got a running motor mate, so no joy yet. it could still be a month or so before it is rebuilt. if u need it back just let us know and i'll post it on for ya.

 

my posting has been a bit out of sequence.

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Originally posted by Terry S

so the engine won't actually catch on the 650's?

 

it wont for ages, then it just does out of nowhere, after its been left for a while. it just cranks, it doesnt even try catch, but when it does it just starts. we have fuel pressure and dry plugs. i expected to pull a plug and see it wet through. the coil loom isn't in great shape which also doesnt help, but it seems to b making good contact. when its running its fine (except for no number2 turbo occasionally), no stalling or hesitation.

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just a bit of an update. the car starts fine first time if the SAFC (LO 1krpm) is set to +20% when starting from warm. the car also has a MINES ECU fitted, this seems to have some different coolant temp vs enrichment map than stock ecu. we r trying a stock ECU this weekend (cheers terry).

 

still cant make the sequental system work correctly though, bastard.

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Originally posted by eyefi

just a bit of an update. the car starts fine first time if the SAFC (LO 1krpm) is set to +20% when starting from warm. the car also has a MINES ECU fitted, this seems to have some different coolant temp vs enrichment map than stock ecu. we r trying a stock ECU this weekend (cheers terry).

 

still cant make the sequental system work correctly though, bastard.

 

That's odd, I've found that the idle and warm-up needs serious leaning-off of the airflow to work properly, yet you are boosting it by 20%? Hows that work? Those MINES ECU's are a pain in the ass for piggyback tuning IMO...

 

What's up with the sequential system then?

 

-Ian

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Just out of interest how much stuff was actually swapped on the car in the period of reliable starting to unreliable starting?

 

650 injectors

Aeromotive

Fuel Pump

SAFC?

 

No flat battery or jump starting or anything like that?

 

Anything ignition related like plugs or coli packs? Have they been disturbed at all? Disturbed/damaged any wiring at the ecu connector if/when SAFC was installed?

 

Are you getting reliable spark when cranking 100% of the time?

 

SOunds electrical to me, any fault codes from the ecu?

 

Ian - what issues have you had with the Mines ecu?

 

Dudes seems fine with his piggybacks and Matt only seems to have that rich point at seq changeover point with the EManage on board, no start up problems.

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terry, i'll give him a ring.

 

ian, yeah it seems weird. richard just tried it randomly and it started. we thought it was just coincidence, but it works every time. it hasnt been checked with the wideband yet, but its almost a stock start, probably about 1.5 crank rotations.

 

the sequential system is playing the old run ok, sometimes late no2, sometimes no no2. it has new turbos (hybrids), we have swapped the 3 main vsv's (air/exhaust/ prespool) and actuators (air/exhaust). cant find any leaks in the pipework and it has a new pressure tank.

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dan,

 

starting to not starting when hot (starts fine from cold), things that changed:-

 

plugs

pump

FPR

650cc's inj

SAFC set to -18% in general

 

none of this has been done by me. the ignition loom has some broken connectors, so is not in great shape, but runs fine once started. spark is regular (at least on no1). plugs where dry but a bit brown (rather than buff) after a few hundred miles, a bit rich and cans of octane booster crap. no errors in ECU. no jump start that i know of. i havent checked the loom yet.

 

is the same thermostat used for the temp gauge and ECU?

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