2007 phazer - cold start ECU (UPDATE)

[stingray719]

Re: Phazer Update

hi folks, i just picked up a 07 MTX Phazer a month or two ago and now that the weather has become WINTER it is a bugger to get going. actually when it's this cold it won't start at all. even if i boost it and get it turning over quick, she won't fire. warm it up and no issue at all.
it only has 1300km on it. i am thinking i really need this Cold Start ECU that i keep reading about.

it was just at the shop for a oil change and some warranty recalls but the ECU one has expired of course. any options on where i can get one? i assume the MTX is different than the GT??

thanks for any help.

I bought two for my Phazers on Ebay....paid 50 bucks for one and 125 bucks for the other. Supercharged Phazer helped cold start and idle, Turbo Phazer helped cold start idle and low speed...odd huh?

 

[rocklong]

Mine was the same way. I changed the plugs and it a lot better.

 

[Ruggybuggy]

Re: Phazer Update

hi folks, i just picked up a 07 MTX Phazer a month or two ago and now that the weather has become WINTER it is a bugger to get going. actually when it's this cold it won't start at all. even if i boost it and get it turning over quick, she won't fire. warm it up and no issue at all.
it only has 1300km on it. i am thinking i really need this Cold Start ECU that i keep reading about.

it was just at the shop for a oil change and some warranty recalls but the ECU one has expired of course. any options on where i can get one? i assume the MTX is different than the GT??

thanks for any help.

I found a kit on Ebay for $150 shipped. I save around $100 from buying it from the dealer. The Yamaha part # is 90891-50146-00. Most who install the kit never put in the decompression spring.

Please fill out you location for your profile. I figured i'd tell you before a moderator does and welcome to the forum.

 

[swixtt]

Great. i have got new plugs in and that didn't seem to make one bit of difference. in fact after fuel soaking them i pulled them and went to a fresh spare.
i am hoping to get just a ECU, no Spring.
so is the MTX the same code ECU as the others?

found this...
ID MARK:

FOR MOUNTAIN
LITE MODELS

(90891-50145-00):
ORIGINAL: 8GP-00
NEW: 8GP-10

FOR OTHER MODELS
(90891-50146-00):
ORIGINAL: 8GC-00
NEW: 8GC-10

 

[Ruggybuggy]

Great. i have got new plugs in and that didn't seem to make one bit of difference. in fact after fuel soaking them i pulled them and went to a fresh spare.
i am hoping to get just a ECU, no Spring.
so is the MTX the same code ECU as the others?

found this...
ID MARK:

FOR MOUNTAIN
LITE MODELS

(90891-50145-00):
ORIGINAL: 8GP-00
NEW: 8GP-10

FOR OTHER MODELS
(90891-50146-00):
ORIGINAL: 8GC-00
NEW: 8GC-10

Is that for a new ECU and what was he asking? I personally wouldn't by used considering you can get on for $150.

 

[swixtt]

i found one for the MTX model. hopefully i see a change in it.
that info came from the Service Bulletin from Yammy...i will post back when i know. it is a new one.

 

[Mountaintech]

I have a 2007 MTN LITE in the shop with the cold start problem. It has the original 00 ECU. 20 seconds of cranking before it starts to sputter and eventually catch. Tried an experiment this morning. Disconnected the fuel pump plug. Cranked it about 5 revolutions and reconnected plug for 6th crank and it caught right away.

 

[swixtt]

Hmmm, that is good to know. Where is this plug? Can u snap a pic of it?
I want to try that on mine tomorrow a.m.

 

[Mountaintech]

Hmmm, that is good to know. Where is this plug? Can u snap a pic of it?
I want to try that on mine tomorrow a.m.

Easy to find. Take off the shroud that covers the fuel tank. You'll see the gray plug immediately, right beside the fuel line connection.

 

[swixtt]

Great. Thx.

 

[Ruggybuggy]

So your thinking the sled is over fueling when it cranking while it's cold? Unplug the pump, crank it a few times to "wake up" the sled before dumping fuel in the cylinders.

I just put the cold crank ECM in my sled and about one out of ten times it will still crank for a prolong time.

 

[Mountaintech]

That's exactly what I'm thinking. When it finally does start it's like it is clearing itself out from being flooded. I spliced into the red wire that goes to the fuel pump and am adding a weatherproof Normally closed spring loaded push button switch. Then the procedure to start when cold would go as follows.........Push down on switch, turn key to start, let go of push button switch after 5-6 revolutions and engine starts.

 

[Mooseman]

From what I remember, it apparently has something to do with oil pressure. The old ECU would wait for oil pressure to register or build up before letting the engine start. Even when it wasn't that cold, it would take like 6-8 revolutions before mine would start. It was cut down in half after the update. I think the replacement decomp spring helps it kick in at lower cranking speed.

What we have to remember is that it's always harder to start any engine the colder it gets. The battery has less power and the oil is thicker, sometimes like caramel, making it harder to crank. At some point, it can be so cold that it may not start unless some extra measures are taken, like a block or oil heater.

 

[Mountaintech]

From what I remember, it apparently has something to do with oil pressure. The old ECU would wait for oil pressure to register or build up before letting the engine start. Even when it wasn't that cold, it would take like 6-8 revolutions before mine would start. It was cut down in half after the update. I think the replacement decomp spring helps it kick in at lower cranking speed.

What we have to remember is that it's always harder to start any engine the colder it gets. The battery has less power and the oil is thicker, sometimes like caramel, making it harder to crank. At some point, it can be so cold that it may not start unless some extra measures are taken, like a block or oil heater.

I agree. Seems to me that with the old ECU that fuel is introduced as soon as cranking begins, but ignition doesn't start till a certain amount of oil pressure is reached.......a recipe for flooding.

 

[Ruggybuggy]

You could confirm your theory. Crank the motor over 5 times as normal but turn the key off before it starts. Pull the plugs and inspect to see if they're fuel soaked.