Problems with Cold Start

For discussing B&G MS-I/MS-II set-up and tuning of fuel parameters (including idle valves, etc.).
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xpernet
MegaSquirt Newbie
Posts: 1
Joined: Mon Oct 13, 2008 4:09 pm

Problems with Cold Start

Post by xpernet »

Hey guys,

Ive had my car running on megasquirt during the summer with no problems. Now as its getting colder, the car is getting progressively harder to start. It runs on 2-3 cylinders and backfires pretty bad. I have to hold the gas pedal while starting the car to keep it running. Once it warms up, car runs on all cylinders and its like as if nothing happened.

The car is a 1977 924, and used to have the CIS crap along with the Bosch air bypass... which doesnt work. So i dont have any form of idle control but the car had no problems starting and idling in the summer.

I tried playing around with WUE & ASE but i still cant understand why the car is misfiring pretty bad.

What am i overlooking?

Sal
stevemgb
MegaSquirt Newbie
Posts: 11
Joined: Tue Dec 23, 2008 9:22 am

Re: Problems with Cold Start

Post by stevemgb »

It could be too weak/too rich at the new colder temps.This could be too little wue/too much wue or, as I found out by trial and error , my car was too rich not due to too much fuel but too little air,which could be your problem as you say you need to open the throttle(I to use a bosch extra air valve but it was too small for my car so now I run 2 of them as I could not easily find a bigger one) Steve.
EWflyer
Helpful Squirter
Posts: 40
Joined: Thu Jul 30, 2009 12:00 pm

Re: Problems with Cold Start

Post by EWflyer »

I think you're right about the "needs more air" side of the cold start issue. I'm dealing with a similar issue on my little Kawasaki EX-250. After messing with the fueling until I'd tried everything I realized I needed better control of the air for cold starts. I need to switch from a simple FIdle to something like a PWM Ford valve that can vary it's air input.
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