Need some help please. My motor cranks over about 5 seconds to long only when cold. I don't have any mecanical problems just to rule that out. My question is what tables can i use to start up my motor with an Ideal mixture( also increase or decrease number by how much?). See I'm running lean at startup/idle accourding to datamaster. I'm about 10 degress advance in my low RPMs and need that extra bump of fuel.

 

Well, you will have something to do with afterstart enrichment.

Might matter some here if your car sputters and then cranks or I wouldnt worry about it yet if it just cranks however.

Look for an open loop vs. table.

Prolly have one for temp and a second one for load.(laptop temp dead or I would look at my TC)

Add some fuel at lower temps this is occuring at and see how it goes.

edit: Great link in the stickies up top I believe its called "cold starts" has lots of good info.

Also sometimes playing with them in tandem with IAC settings can help, but if u do this go slow, too far and its all messed up again.

later
Jeremy

 

cool I'll check out the stickys too.

 

Well When it startup it's running pretty good, just fires up. doesn't really sputter or anything it just take to many cranks and logging says she's lean. This all seemed to happen after my porting job. I'll still need to ajust my MAF tables too because she's lean in closed loop too when idleing.

A while ago I had a Burnoff code, but since then it's not come back. I think it was a fluke.

So the open loop are really the best place to make ajustments huh. Asking best i see a few tables labeled start up or crank fuel. Just want to make sure i get the correct area.

 

My start up even takes longer than that when cold. Hot its fine. I had modified the crank PW, and start up tables in the AUJP. The only thing I can think of is the initial timing set at 6* in the eprom. Maybe it might need to be more, say 8*. My C/R is 11.2, on my 436, but it did this on any engine I had the S/R on. I can try the additional timing, but if it fails, then I dont know what else to try.

 

Crank PW vs Coolant temp if it's hard to start when cold.
You might compare the s/u fuel tables from different bins too and try a different bin's settings.

 

Is the oil pressure switch bad??

 

The oil pressure switch? No it's fine. w ould that cause hard start if bad?

I'll mod up them table later today then data log it. I think after porting my intake the A/F mixture changed a little. so i need to bump fuel more.

 

Thanks Scott. Good idea about the other bins. I'll give it a try.

 

Also, the VE tables/OL stuff has no effect till immediately after start up.

 

I might be imagining things, but isnt there also a DRP based delay that delays the injector firings when the engine initially starts cranking cold? Ill have to go back and look.

 

Yeah, the stock table that I used had 8 DRPs (2 revs) of delay built in. I changed it to 2 DRP delay, and it starts with a bump of the starter almost.

There's probably reasoning behind delaying it, such as making sure the operator really wants to start the engine vs. electrical noise or someone turning the engine slowly with a wrench; and maybe to get the oil circulated just a tad more before it starts.

It could be a problem with the fuel pump relay, and it's relying on the oil pressure switch to power the pump. Does the pump turn on for two seconds with just key on?

 

Where is this DRP table I'm using a 6e?

 

Check out your Crank Fuel PW Multiplier vs. Ref. Pulse table. Stock 6E bin will have the first 8 Ref. Pulse set to 0.

 

Could be your battery does not have enough cold cranking amps. For harsh winters you need a battery that has the most cold cranking amps that you can get. Check out how many you have and see if its low. It could also be a combo of that and your starter going (slowly.) I had the same problem and i got a new battery with hella cold cranking amps and replaced my starter with a new one. Mine works fine now no matter what the temperature is. First turn starts motor in less than 2 seconds

 

nope battey is good same with starter. yeah the first 8 Ref. Pulse set to 0 thats true. the rest are set to .25 and .20 what should i set it too and which ones should i change?? what does it do going higher or lower please.

 

ummmm
if you change those it affects the starting hot, cold, and in between. Read the sticky. Plenty of info... and the answer to your question.

 

RednGold86Z can you show me the light on this Crank Fuel PW Multiplier vs. Ref. Pulse. i find nothing about it in the stickys.

Whats it do when i increase or descrease? 1-8 is 0 and 8-24 is like .50 .25. 20. rather not f it up.


Thanks

 

Just "shift" them all down to the earlier spots (cut and paste basically). This should NOT fix your problem though actually.
Sounds like you're having some other problem.

If it's just cranking too long, and you want to add some more fuel to the cranking PW, just raise the "Crank Fuel PW vs. Coolant Temp" values at the colder parts only. Cranking fuel can be changed by 15% or more at a time, if you want to see results. It may actually be getting too much fuel, though, so if 30% more doesn't fix it or at least improve it, try the other direction.

How are you deciding that it's running lean at idle according to datamaster? Are you using a wideband? Is AIR still installed and enabled?

If it fires right away, but flares and stalls, you might want to try the afterstart fuel tables (03ED, 14 rows, .390625*X), and maybe the afterstart spark, but spark should only be a very minor help.

 

OK I think i got it man. Might be lossing you here. Sorry let me explain. First off it's a 88 vette with the silly 9th injector. I was using 32b chip until i started having issues with the ninth injector. So i disable the ninth injector and slapped a 6E chip it helpped a lot but still cranked a little to long. So i've learn to deal with it until lately it's been kinda pissing me off. So i did everthing this post last night and fired it up. It cranked for maybe like 2 seconds and it fired up nice. but it ran rich as hell. So what i'm going to do is just ajust the Crank Fuel PW Multiplier vs. Ref. Pulse and try it again without adding fuel. Then if need be i'll add more fuel as needed.


I'm dataloggin with DM, and i found that it's running lean at idle and startup but i think because i 'm runing a little to advanced on my timing. So i've totally went back to stock on my chip and kinda starting from scrach. only mods i'm making are TCC,coolant temp. So i can figure out whats going on with it. Thanks for all your help everyone.

 

Are you using a Vette 350 L98 .bin? Which one?


Have you done other mods to the car?