FC / E6X - Hard to start
 

I am looking for some help with my car as it is often very hard to start. I am wondering what I can adjust in the Haltech settings that might help. Once the car starts, it runs great.

When I try to start the car, I crank it for a few seconds. Then wait about 20 seconds. Then crank it for a few seconds. Then wait about 20 seconds. Then crank it again, it stumbles then finally starts (I usually have to hold the pedal to the floor). Sometimes it stumbles for a good 5-10 seconds before it will finally start.

Also, what should I set my fuel pressure at when the pump primes? 40psi?

Any advise would be appreciated. Thanks :icon_tup:

EDIT: MAP attached

40 PSI is good base pressure

Assuming all electrics/mechanics are 100%, excessive cranking during start up means you are too lean. Add fuel to the primer map. You should NEVER have to press the gas pedal during cranking. All engines are different, but I found on mine (turbo 2, mild street port) I needed a lot more fuel under 70 degrees than above.

Overall, add more fuel to the primer map.

PS
I haven't looked at your map because I am at work. Try not to use too much timing at cranking either. I only use 3 degrees.

Thanks, I will give that a try

I agree that you should try adding more fuel first.

If that works on your engine that's cool. But 3 degrees is actually less than stock:

https://www.rx7club.com/attachment.p...1&d=1308022874

OP's cranking timing map is this:

https://www.rx7club.com/attachment.p...1&d=1308023037

if adjusting the fuel doesn't help enough, I would add 5 degrees across the board. OR just set the entire map to a fixed 20 degrees at all temperatures. I know that sounds like a lot but I've seen it help on a lot of engines, especially ones that don't have the fast idle/thermowax installed.

thanks a lot, i'll give it a shot tomorrow and report back :icon_tup:

i changed the timing and it didnt help. which fuel map are you talking about? the post start enrichment map? i put each bar up 4 "clicks" and it didn't help either. what should i set it to? i have 720/1600's and the tb mod done.

Fuel primer map

thanks, ill try that tonight

When I start my car, I put the key to on and let the engine prime. You will hear the pump run for 3 seconds or so. Right when the pump stops I crank. My car starts consistently. I haven't had a problem yet.

well i went home on my lunch break and it will not fucking start at all now. :mad: i tried changing the fuel priming and ignition cranking maps and it cranks and cranks but wont start. i am going to check/change the plugs when i get home later and try again.

can you send me a screenshot of your fuel priming and ignition cranking maps? what injectors are you using?

i am wondering if maybe my battery is the issue? it sounds like it is cranking well though. i think it said 188rpm on the haltech while cranking. is that fast enough? i also tried jumping it with my DD and it still would not start. what do you think?

When I get home from work I can post specifics regarding my map. I have the older E6K, but fuel is fuel. When cranking I only see 180 on my screen, but the older E6k only displays RPM in increments of 60. I replaced my aging starter a few months ago and it does sound strong(er). Again, I have ZERO trouble starting.

i swear, i have never not had trouble starting this damn thing. i just had my battery and alternator tested and both are good. battery put out 207cca.

OK like I mentioned, I have 3 degrees in my ignition cranking map all across the board. I say try doing 5 across the board like the stock engine/ecu does.
I am running 550x1600 injectors, so you probably don't need quite as much fuel as me.

At bar 9 of the primer map (72 degrees) I have 65.5ms. You have bigger injectors, so I figure you can try 53ms. At bar 25 (185 degrees, fully warmed up) I have 24.6ms. That's probably overkill, you can probably use 10ms there. Then select bar 9 to bar 25, and linearize. If it's even cooler than 72 degrees out, just add more fuel to the bar before that, try increments of 7 or 8ms.

Of course, always double check you stabbed the CAS properly.

Like I said, I have no problems starting my car. When I was setting up, if it didn't start within 3 seconds, I just added 5ms to whatever bar I was on in my primer map until it worked.

I think I'm getting the hang of this :)

i havent touched the CAS...i will go change the plugs and try those settings. thanks

I would also verify your leading coil is working. Mine was on the fritz for nearly 1 year and eventually crapped out. However, I never knew that it was my problem. Some days the car ran perfect, others I could not get it to start, or it ran like total shit. leaning out all over, or running pig rich. I kept playing with the tune and finally realized something is wrong besides the tune and was able to diagnose that my leading coil was kaput.

what would be the best way to test it? just aim a plug towards the chassis to see if it arcs? i've got a spare i can swap.

What I did was disable my injector outputs (so I can't hear the injectors). Then I took the CAS out, but left it plugged in. With the key to ON, I would spin the sensor by hand as fast as I could (so the ECU sees a speed signal). It will fire the coils. You can hear the leading coils ticking. You may want to unplug the trailing coils so you have a clear ear just for the leading (which is what you really need).

It's crude, but it works.

i think it wasnt starting because the plugs were fouled. i swapped them out, pulled the fuel pump fuse and it caught for a sec and shut off.

why do you say 3 or 5 degrees, but arghx recommends 20? isn't that a big difference? my numbers on the fuel priming map are different than yours, i need to look at that for a few minutes. can you post a screen shot of yours if its not too much of a pain? i can send you my email address so you dont have to upload it somewhere. are you using degrees C? or F?

I use 3 degrees because hey, it works. Honestly, I could probably change it to 15 and it would still work, but I don't need to find out. Stock is 5. True, none of our motors are stock, but it's a starting point.

I only have minor porting done. I don't know what you have done. My 900RPM idle pulls 17/18 inches of vacuum for reference. I am not too extreme, so I don't need to stray too far from stock.

ArghX knows his shit, so if he says 20, it probably does work. However, I think you can/should start low.

It's a PITA for a screen shot as the E6k uses DOS, but I suppose I can whip out the camera!
Be back soon!

if you send me your map i can load it on my computer. i have an atkins "streetport", nothing crazy. i'm waiting for my battery to charge and will try to start it again in a bit.

Primer:
http://img.photobucket.com/albums/v6...le/primer1.jpg
http://img.photobucket.com/albums/v6...le/primer2.jpg
Cranking:
http://img.photobucket.com/albums/v6...e/cranking.jpg

cool, thanks

any news?

i literally just walked in from the garage. i didnt have a chance to mess with it last night because i was waiting for my battery to charge and i had to work at 6am.

i set the timing to 5 and raised the fuel a couple clicks. it cranked for a second or two and started right up. it felt like it was running on one rotor for a few seconds and then was fine. i think i need to keep tinkering with it but that's the name of the game for rx7's i guess.

i'm still not sure what to leave the timing at but whatever works i guess...

ive got it dialed in from ~70 to ~200 degrees...my fuel maps are higher than yours but im trying to use 20 degrees of timing across the board to be consistent. it's been starting right up. ive probably started it 25 times today alone. :icon_tup: