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Discussion Starter · #1 ·
I have a T5 equiped 900 with a cold start problem. Cold temps (below 15 C) and there is no cold start. If it is below 0 C. I have to use starter fluid to get it to fire. (Car fires right up). Have to crank the engine 2-5 attempts before it will start barely. Warmup after that is fine. Coolant temp sensor is working as it is verified by display panel. Fuel pressure is good, manifold sensor is also working. TPS switch displays 0-207 on the display panel. Voltage is 10.2 volts during cranking as displayed on dash mounted volt meter. My before start parallel injection (before start) settings are 9-156. It is getting colder and I would really like to figure this out. The car does this with both ECU's that I have tried. (stock '94 auto and JZW tuned '94 manual).
 

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i love post like this, i make ones just like this when i am overly frustrated an have tried almost everything.

do you have an aftermarket fuel pump, or injectors?

have you pulled the injectors out and watched them fire?

mike
 

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Discussion Starter · #3 ·
Checked more things out this morning.

Great idea about pulling the fuel rail and watching the injectors. I have always felt that I was just not getting enough fuel. The car always fires briefly on the the second or third crank attempt but never stays running. Yesterday when it was 10 degrees C I had to crank it 6 times to stay running. Like I said previously, It will not start without starting fluid when it is below freezing. This morning I checked fuel and the injector firing at start. All my injectors are definately NOT parallel firing when I crank the engine. I watched the injectors and they don't fire together. I did get fuel but it was a small amount for a cold start. Tested the fuel pump for output. Holds 80 plus PSI for five seconds with the return line clamped. FP gauge on the fuel rail shows 40-42 psi with the fuel pump jumped to run.

Mike...you find anything in the bin that I sent you?

Grrrrrr......vexing problem. Car runs great otherwise.

Gregg
 

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Try pulling your fuel pump fuse. I had this problem last winter before I tuned it, all I had to do is pull the fuel pump fuse and crank it until it fired and ran for a second. Then put the fuse pump back in and it would fire right up and run with no problem. mine was getting way to much fuel and flooding out in the cold weather.
 

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Discussion Starter · #5 ·
Mike D played around with my bin and sent it back to me. Going to try and add fuel to the cold cranking settings and see if that helps. He made some other changes that made the car go like a scalded dog...Wow....thanks for that. So cool....email the bin to Mike, get it back and download it (T5 automatically asked if I want to synchronize the bin that Mike sent with the one in the ecu.,, yeppers) in about two minutes and go for a drive. T5 suite is awesome. Now that I can communicate with the ecu and getting a handle on T5 suite, I am impressed with what a great engine Management system it is for the C900. Will give feedback when I have tried a few cold starts with the modified bin.
 

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im pretty sure the injectors will never fire all at the same time on a T5 car, they are sequntial which mean they fire based upon which cyl is up next.

Jetronic is batch fire, so they all fire together, T5 it should never fire all at once

Stupid question, are you positive each injector wire lines up with the corisponding Cyl number??

if it is getting to much fuel, try turning off the "erichment during cranking" setting in the firmware. OR altering the settings in the

Startvev_fak!
map
 

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im pretty sure the injectors will never fire all at the same time on a T5 car, they are sequntial which mean they fire based upon which cyl is up next.

Jetronic is batch fire, so they all fire together, T5 it should never fire all at once

Stupid question, are you positive each injector wire lines up with the corisponding Cyl number??

if it is getting to much fuel, try turning off the "erichment during cranking" setting in the firmware. OR altering the settings in the

Startvev_fak!
map
I recall a conversation with Rob Walden from Scanwest and he mention during start up the fuel batch fires the injectors and the DI fires the plugs on the power and exhaust strokes so it can sync the cam via the ion sensing in the DIC. Once it "see" that it goes to sequential fueling.
 

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ive heard that about the DI fireing all at once, but never the injectors...

i guess somebody would have to test this
 

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Discussion Starter · #9 · (Edited)
Parallal injection....

Started great this morning. Maybe all I needed was more fuel. Glad to know that there is not a problem with the hardware and sensors on the engine. Will keep playing with it to get it right. If you install T5 you really need to be able to get into the ecu and make changes to the software for the c900. I have been trying to solve problems without any information. Plus, there are a number of settings that work better for c900's when they are changed. Looking forward to getting a wide band and tuning for the larger turbo on my car.

Congrats to Dennis (Squabb) on being a first time Daddy!! You must not be getting much sleep right now!

All the injectors hooked up correctly??? Hmmm...Pretty sure there are no mistakes with my harness :) Will check it when I have an extra set of hands.
 

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Greg; did it start up good with the changes i made? or were there more changes needed t make it start ok??

mike d
 

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Discussion Starter · #11 ·
Started great twice...

This morning and after work. Did not act starved for fuel and fired up quickly both times. You may have nailed it right the first time. If not it will be easy to add small increments of fuel to the startvev.fak map. Thanks for doing that Mike. I have been thinking it was a hardware problem with the car when all I needed was a tweak to the software......
 

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Started great this morning. Maybe all I needed was more fuel. Glad to know that there is not a problem with the hardware and sensors on the engine. Will keep playing with it to get it right. If you install T5 you really need to be able to get into the ecu and make changes to the software for the c900. I have been trying to solve problems without any information. Plus, there are a number of settings that work better for c900's when they are changed. Looking forward to getting a wide band and tuning for the larger turbo on my car.

Congrats to Dennis (Squabb) on being a first time Daddy!! You must not be getting much sleep right now!

All the injectors hooked up correctly??? Hmmm...Pretty sure there are no mistakes with my harness :) Will check it when I have an extra set of hands.
Thanks Gregg, Yep the Sleep Map is running a bit lean, but it is so worth it. Kinda like this Engine management stuff. A lot of work to get up and running. Soon I'll have her changing my oil and being a brake bleed helper.

Your injector hook up should be fine. Since it runs sequential the engine would run lean on any type of load or even idle. If they were mixed up, the injectors would shoot on any other cycle besides the intake and it would run like ass.
 

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Your injector hook up should be fine. Since it runs sequential the engine would run lean on any type of load or even idle. If they were mixed up, the injectors would shoot on any other cycle besides the intake and it would run like ass.
Hey maybe thats my problem with running lean at any start but not in close loop!

Cold start is okey but after 5 seconds it start running very lean (leaner than AFR19.5!) with a stock bin. When its on close loop it runs okey but not in open loop (very lean).

I adjusted the VE scaling map 4 point higher than stock (21 to 25) but its drinking fuel now like i normal only do in a bar on Saturday night!!:mrgreen:

So i tryed it with the Batt_correction map but same high fuel consumption:-?.

So Cilinder one is at closed to the firewall right?

And right next to it Cilinder 2 and so one?

Cilinder one-injector one.
Cilinder two- injector two??
Ect,
Ect,

Thanks!;)
 

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Discussion Starter · #15 ·
error message

I keep getting "sond_error" with a value of 44. This is under the DTC (error code) tab in T5 suite. I still get a reading from the o2 sensor on the real time panel. Should I be concerned about this?
 

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Yeah....whats your AFRs?

Mine had the same problem, but I still got an AFR reading, either wicked rich, or wicked lean.

New o2 fixed it.
 

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Discussion Starter · #17 ·
sond_error

Drove around with the lap top and the a/f ratios are all over the place. Varies from 12.7 up to 15.5 at idle. Is not consistent. Same for driving around, varied a/f even though it is in closed loop. Ordered a new O2 sensor. Have a wide band coming as well to try and get a reading via pin 69. Slowly getting there......
 

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Now am starting to think that the preheater may not be powered correctly...and or, youre using an OBDII harness and didnt ground out the O2 reference ground.

When I said it was wicked rich or lean, I'd only see like an AFR of like 10.2 or 20.something.
 

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ive heard that about the DI fireing all at once, but never the injectors...

i guess somebody would have to test this
You are right. It would have to be only cyl 1 and 4 or 2 and 3 injector batch fire on both the intake and power stroke. After is see what stroke cylinder 1 is on it switches to sequential injection, and of course spark.
 
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