I have many issues..lol. I'll check the pump indicator in megatune...it thats correct its a output (transistor) issue. The injectors are bran new so they shouldnt be leaky. I went with the 720's knowing it could cause idle issues. If I went with 550 primaries I would need 1600cc secondaries or close to it. Injectors are like diamonds the bigger they get the more they cost. Just one pair of 1600cc injectors is usually around 300.00 thats if you can buy just 2. I will eventually change to 550 primary and huge secondaries,but right now I have these new 720's and want to see how well I can get them to work. Im use to lumpy idles as this is a ported engine and my previos engines have been as well. Anyways thanks for the tips guys headin back to work.

 

Ok once again you guys were right. I adjusted the req fuel in the constants settng ..no problem there....it almost started. The cranking pulse widths from what I can see is a series of several values according to temperature. I have no clue what to enter. Unless theres a seperate feature Im not getting into? I have megatune 2,25b514 and MSNS extra 0249s. On the fuel pump indidator it is working properly. Upon booting it stays on for a couple seconds and when cranking it stays on..it goes off when theres no RPM's. With that problem I must have a bad transistor somewhere. The fuel pump never worked from day one so either I have a defective part or ESD zapped a transistor on me. Thanks again,Shawn

 

well it's either wiring or the transistor...

next time you go to start it, try cranking for a few seconds, then push the throttle down while cranking... see if it starts once you do that.

Also, if you're using the cranking pulse-widths from the FAQ, they're ALL going to be much too high... I'd subtract at least 2 ms from each value... (remember the values in the FAQ are only tuned down to 60 degrees F... I never tuned below that).

Ken

 

Thanks for the tip on the values. I'll adjust those now. Ive tried cranking and holding the throttle slightly open...no go. Its definately not the wiring or a code problem so that leaves a transistor or other output component.

 

don't hold it open until you've cranked for a while... otherwise you won't get any fuel...

Crank it for like 2 or 3 seconds, then open the throttle while cranking....

I've had 2 or 3 MS installs that wouldn't start the first time without doing that. Once I got the idle and everything tuned, I went back and adjusted the amount of fuel going in, and now I get the engine to fire up first try every time no problem.

Another thing you can do instead of lowering each value is you can lower the priming pulse width... That will have the same effect as reducing everything in your cranking table a bit.

 

Well I reduced all the values in the cranking table by 2 ms. I tried cranking for a while before opening the throttle. I think its flooded. You know how stubborn these engine can be to get unflooded. The battery also is run down a bit. I charged it overnight. I will remove the spark plugs and crank it to help remove excess fuel today and unhook the db37 on the ms so theres no spark. Im also thinking of getting a can of starting fluid although I hate using it. Any other ereas I can adjust the fuel flow? I wasnt sure if the fuel or ve maps were into affect while cranking? Thanks again Muy Im almost there.

 

if you're getting flooded and the engine isn't starting, your CAS could be misaligned... If the cranking spark advance is too retarded, the engine will act like it wants to start, but will never quite get there.

Also, to unflood, it should be as simple as holding the pedal to the floor (and looking for the FLOOD CLEAR indicator in the bottom right corner of megatune), then cranking. If your leading plugs are sparking while doing this, it might even start the car once enough of the fuel is gone (assuming the CAS is aligned properly).

 

Good call on the CAS. Its simple yet easy to screw up installing it. I followed the same procedure as installing a dizzy. I turned the front pulley clockwise until the timing pointer lined up with the yellow mark. Then on the bottom of the CAS there is a dimple and a mark on the gear just like a dizzy. I lined up those marks and carefully stabbed the CAS in . Yea I see the flood clear indicator when I give it full throttle. I just like removing the plugs because the fuel likes to puddle inside them. Ive noticed in the past when having starting issues that removing the plugs cleaning them with a shot of carb cleaner and blowing them out with compressed air seems to help a lot. I do not have trailing spark yet. Its all wired in but not working. Either my version of firmware dosnt support it or I have a bad coil pack. Megatune 2.25b514 and MSNS 0249s. I installed a fuel pump cut off switch and Im calling that problem fixed. I also noticed my ztx688 ckt is not opening the BAC valve. When installing the ztx688 I did get 12 volts from one side of the PMOV,maybe that not a good source? For now I just wired the BAC to ground and the other side to switched power so when the key is in the run position it opens. With it wired like this is when the car really wants to start. Before I was holding the throttle 3% open after cranking a bit and building oil pressure. Do you see a problem with the BAC being open all the time with the engine running? I can try advancing the CAS next and see what happens. Its ok if my timing is way off Im not going to attempt driving the car in the snow. And before and engine running above idle I'll get my timing light on it. Without it running tho its kinda tough. I have 2 kerosene heaters in the garage and I always warm it up thinking it will help the engine cough to life. Om cranking I get a max of 250 RPM and 95 to 97 KPA and the AF ratio gets all over the place. I think once I get some exhaust blowing past the 02 sensor it will read more steady. Time to get the heaters goin and get this thing running. Thanks again.

 

trailing won't turn on until you get to 800 rpms... it's working as intended. You should be using one of the 026 series if you want trailing to work. I have a version of 026i with my staged injection transition code that I created since 027/028 have a problem with tach spikes and bad ignition at 4000 rpms.

I'm not sure what's causing your BAC valve to not work... if it's wired with +12v on one pin, and the fast idle output on the megasquirt connected to the other pin, and you followed all my circuit advice, it should just work.

As for the timing, you don't have to get it perfect before it'll start, just try advancing it a bit to get it started... then set the timing on the MS to -5, and turn the CAS until the timing lines up.

 

kewl thanks for the timing tips. Do you think having the BAC open whenever the engine is running is a problem?

 

I advanced the timing a small amount and still nothing. Its not even stumbling or wanting to start any longer. My narrowband 02 sensor ir reading full rich. I have a display for that on the dash. Something is way off. Im trying to walk away from it and think.

 

yeah, I mean at that point you're probably flooded.

Having the BAC full open will just make the car run at like 3000 rpms....

 

Ok I thought the BAC was either open or closed. I didnt know it partially opened.

 

you can set it up to use PWM Idle control... Higher duty cycle will open it further... lower duty cycle will open it less. Mine is fully closed between 20 and 24% duty, and I have it set to be at about 46% when the car is started cold. It gradually closes as the temperature goes up.

You can also set it up to control the idle speed all the time for use with things like the AC for idling up when the AC comes on.