Tiger running poorly - things to look for please

[ChazzyB]

:idea: what alarm are you running

Alarm; what's that? There was one on a Speed Triple I bought. I soon removed it.

[Bixxer Bob]

Don't forget to check the ECU relay first, it's only a 3 second job and you might be lucky!

[ChazzyB]

Don't forget to check the ECU relay first, it's only a 3 second job and you might be lucky!

This is the main power relay - 71 in the factory wiring diagram?

[ChazzyB]

There's an audible click from one of the underseat relays about 3 seconds after power off. Dunno which one - there are two identical jobs next to each other.

[metalguru]

If it does turn out to be the stepper motor I have been looking around and a renault megan looks similar but have not compared yet. They are only £20 new! French made efi so could be similar cos stealer is bound to be £80. Just a thought there is another of your favourite o rings between the stepper motor and the body if that has gone on holiday or somehow escaped or even worn out it could give problems.

[Bixxer Bob]

There's an audible click from one of the underseat relays about 3 seconds after power off. Dunno which one - there are two identical jobs next to each other.

That's the one.

[ChazzyB]

I fitted a different IACV stepper yesterday morning. Initial results seemed good (several start and stop cycles standing on the drive and no probs). Went out to get some petrol and guess what, on restarting, the problem's back again. I rode home with it in a dreadful state and it died as I turned into my drive. I can't remember if I switched off at that point or just clutch-in and restarted. Whichever, I restarted and it was fluffing off tickover. Anyway, after a few seconds idling, it seemed greatly improved, so I went off for a prolonged lanes ride (30 miles, 45 minutes). A couple of times, I stoppped, checked how it was responding coming off idle (fine), let it idle for a few seconds more and then switched off, waited 30 seconds and restarted. Both times, it started on the button, but immediately was fluffing at small throttle openings off idle, almost dying unless I gave it a handfull. I found that if I let it idle for 10-20 seconds, it would gradually improve and become usable. This has been repeatable, pretty much every time this afternoon, too. Once the bike's settled into a usable state, it seems to be fine, barring the usual, somewhat rough, gentle on-off throttle transitions at 2.5-3K RPM.

What's going on????

[metalguru]

Sounds at first like a big air leak but presuming all the IACV pipes have been checked for leaks, I would be inclined to reinput a tune, BBs got a good one, as I have learnt on starting, these cycle through the warm-up map till they figure out how warm they are and settle down, usually high idle for a few seconds then settle down. Might be wise to check the air intake and engine temp sensors for correct voltage (can do on tuneECU). Or it is going through the startup but the map is not supplying enough fuel, again a reload. I am assuming the TPS was reset when replaced, Have a look at ECU settings on this site for voltage comparisons as just got mine right and it may help you.

[metalguru]

Going back a while, you have reported good IACV connection and good excerise on the stepper motor, none more about the scotty. Is the diaphram in the scotty working and sealing ok? Best way to check is with a hand vacuum pump with a guage but if all else fails suck it and see. An air leak here would certainly confuse the ecu (not difficult). Or disconnect it and plug the pipe engine side and have a try.

[ChazzyB]

The Scotty was checked early on. Neither putting a brand new Scotty reservoir on (I just happen to have one 'on the shelf') nor bunging a finger over the end of the pipe wearing my favourite nitrile gloves made any difference.

Current thinking in one quarter is that it could be a ECU fault; not storing trim data at power off. This vaguely ties up with my discovery that if left to idle for a minute or so after a restart, the problem settles and goes away. However, if you grab the throttle immediately after the restart and try to stop it fluffing and choking by giving it *positive* throttle input, it doesn't go away; oh no.

I ran the bike this evening after work. Five minutes or so from cold, without touching the throttle. On the face of it, a perfect start and warm up. I then switched off, waited about 30 seconds and restarted (on the button, no throttle). After another 30 seconds, I tried a throttle blip - a slight fluff, let it idle for another 10 seconds or so and tried again; it kept on improving over the next 30 seconds or so until I reckoned it was as good as ever. After letting it idle for another period, I switched off. After 30 seconds or so, I turned the ignition on again (no lights, didn't start it) and measured the voltage across the battery terminals - 12.3V. The battery's a Yuasa of indeterminate age. It was in the bike when I bought it three years ago. Given that a faulty main power relay can prevent long term trim data being stored on power down and that 12.6V at the battery is the minimum for a successful tune flash, I'm wondering whether a weak battery may be behind my problems?

[metalguru]

Hope the gloves are nice pink ones..lol.
best to check charging voltage aswell if kept on a battery tender.

[iansoady]

After 30 seconds or so, I turned the ignition on again (no lights, didn't start it) and measured the voltage across the battery terminals - 12.3V. The battery's a Yuasa of indeterminate age.

That's really low - I'd expect far more than that even with the lights on.

I find modern batteries don't last long at all - I'm on my 3rd with my 2004 (including the original) - the second one barely lasted 2 years.

As you will know, weak batteries cause all sorts of problems. My current one is a Westco from Tayna which seems pretty good so far.

[ChazzyB]

An ECU bought from a breaker on eBay, £66 delivered next day, has fixed it. Got a VIN and serial number in the ECU again to boot. Not my VIN, but it's a VIN. It even came preloaded with the right tune.

So, what else has been done to get to this point? New TPS (throttle bodies off twice), 4 hours dealer "diagnosis" (Ha bloody ha)! New battery, swapped idle steppers (twice), replaced oxygen sensor. Much gnashing of teeth and wailing. I have learned a lot though.  :roll: Thanks all.

[iansoady]

Glad to hear it.

I know this would be tempting fate but I'd be tempted to try the old ECU again now everything's working just to confirm that's where the problem is. Although the lack of VIN etc is probably evidence enough.....

[ChazzyB]

Glad to hear it.

I know this would be tempting fate but I'd be tempted to try the old ECU again now everything's working just to confirm that's where the problem is. Although the lack of VIN etc is probably evidence enough.....

Nah, I've spent too much time on this problem already. It wasn't just the missing VIN, it was the serial number that had morphed into "FFFFFFFFFFFFF" as well. I keep going out to the garage and starting it as I can't really believe it's sorted. Everything I've tried so far, I've thought "This is it, sorted", but it hasn't been so.