cold start

[dizzle]

I'm having issues starting. Generic Ms2. When I try to start it I have to try several times or I have to hold the key forward for several seconds. When doing so, it sounds like the car has to build up before it starts. I know that isn't a good description, but its like it has to build up rpm's.

42 lbs injectors
Gutted intake
Bigger turbo
Spearco intercooler

Thank you for any help.

[Stinger]

At minimum you'll need to post your msq and a datalog during startup would be ideal.

[dizzle]

data log: sorry its so long. I thought the more that there was the more info you could help me with.

Thanks Curtis

[dizzle]

msq.

[dizzle]

I am not sure these files uploaded correctly.

I didnt know how to add both to one post either. Thank you for any input.

[dizzle]

Just curious to see if I'm heading in the correct direction?

[wesk]

Do you understand the starting and afterstart strategy?

[dizzle]

As much as I hate to admit this, I realy don't understand a lot of this. I have read the mega manuals about 3-4 times and stingers sticky threads lots of times but when it comes down to doing any tuning I get nervous and unconfident. Back to the question you asked, I believe the procedures for tuning the after start involves adding and removing timing and fuel to reach a Target afr reading. My problem is I don't know when it is necessary to do so with "fuel" or "timing". The cold starting functions I am kind of lost on. I did all the start up procedures but I feel that I am missing some thing very important.

I hope this answered your question, but if not I will say the easiest way to explain my understanding of these functions would be to just tell you I have no idea. This way we just start from scratch. I am trying to learn as I go so please forgive me if I ask any questions that seem stupid. Thank you for any advice that you have.

Curtis

[wesk]

I pay no attention to lambda values for afterstart. Prior to tuning afterstart, your warmup enrichment tables need to be dialed in (as those values are also factored in). If (after it is already running for 20 seconds or so) you are happy with the way the engine runs while in warmup mode you can move on to the Afterstart values. When I ask do you understand the strategy, I don't mean how to adjust it, I mean how it works.

There are several components to the starting and afterstart stategy:

1) Cranking fuel PW vs. coolant temperature. When cranking the engine (as defined by rpm<cranking rpm setting) this AND ONLY THIS defines how much fuel is injected. Adjust this if the engine doesn't "catch" quickly at a given coolant temperature. If the engine "catches" rather quickly and then dies, move on to afterstart enrichment.

2) The afterstart enrichment is the additional fuel (expressed as a %) that is added in addition to the normal running and warmup table adjusted fuel. Increase and decrease this value and see how the engine responds. Typically if the engine runs for a few seconds and then dies it needs more. If it dies immediately after "catching" it likely needs less.

3) How long the afterstart enrichment is applied is defined in the ASE taper table. This is expressed in cycles. At time = 0 (as defined by the instant RPM exceeds cranking rpm) ASE fuel is equal to the full ASE amount. At time= ASE taper table value no additional fuel is added based on afterstart (and only the warmup fuel vs. coolant temperature is added). If the engine runs for several seconds afterstart and then dies, try increasing the taper time.

When making these changes, make a large enough change to gauge direction.

[Stinger]

Thanks for the post Wes, sticky created with this info.

[dizzle]

Thank you wes. One question I have now is, if its having difficulty "catching" at a particular temp should I raise or lower the pv ( in Cracking Pulse)

[wesk]

If it isn't flooding raise. Is it establishing sync quickly (displaying rpm in TS)? You can also ctry increasing the priming pulse a little to get an initial shot of fuel, but be careful with priming pulse and relatively large injectors (can flood in a hurry).

[dizzle]

Thank you, I will give that a shot and see what happens.