RX7Club.com - Mazda RX7 Forum

RX7Club.com - Mazda RX7 Forum (https://www.rx7club.com/)
-   Microtech (https://www.rx7club.com/microtech-111/)
-   -   Microtech E85 cold start popping issues (https://www.rx7club.com/microtech-111/e85-cold-start-popping-issues-659591/)

takerwolf 06-05-07 06:46 PM

E85 cold start popping issues
 
Starts up fine when already warmed up, had no problems on gasoline. Just does not want to start when cold, lots of backfire and popping after the engine tries to fire once or twice with some throttle input at times. It takes many tries to get her going and this morning at one point it sounded like someone fired off a gun almost. When she does start up it really rough for a half a minute or so.
Is this a sign of too much fuel, or not enough fuel? Should the timing be changed? Since I've got the water temp timing map, crank map, and water temp injector map, I don't know what to try. I tried adding some more fuel and I thought it got better but that was during warmer weather. Also, the timing split under 1k rpms is 0 for better burning and I did a trim setting of +3 timing to be conservative (compared to gas) with the 105 octane. I tried taking 3 degrees back out at cold temps too but not sure if it helped.

RotaryEvolution 06-11-07 05:06 PM

try changing the plugs, if your plugs are too cold they could be fouling out too quickly.

rx72c 06-11-07 07:46 PM

whats your cold start map look like?

it sounds too lean.

takerwolf 06-13-07 06:23 AM

I've got a new problem to work on :( After a drag run she's only pulling a 9" vacuum instead of 13 or 14" with a bouncy idle 500-600. Was at 900. Then the next day it was back to normal again, now this morning back to the bouncy thing, but the funny thing is the cold start is no longer an issue I did make a few changes though.
Need to check compression I guess, not sure if fouled plugs could have anything to do with it. Before the drag I put in 4 gallons of 110UN (thought they'd have ethanol at the track) then drove back 20 miles to top off with E85 and didn't premix with MMO on account of the gas, hope that wasn't a mistake.

Thanks for all the help, I'll do some investigating later. She seems to daily drive with no power problems or odd behavior aside from the idle.

RotaryEvolution 06-18-07 04:26 PM

let me know what you find, i have the same issue with my car from time to time and haven't had the time to really investigate it. i was thinking the trailing coils are not firing intermittently since i can't find any vacuum leaks whatsoever but i'm leaning towards an ignition issue.


All times are GMT -5. The time now is 12:18 AM.


© 2024 MH Sub I, LLC dba Internet Brands