how do i make my car start and idle (cold) without IAC?

87_7MGTE · Post by **87_7MGTE** » Fri May 26, 2006 6:11 pm

hi,

right now, I dont have a IAC, or fast Idle valve or anything like that hooked up to my MSII for cold start. When I start the car (cold) I have to crank it for a few seconds and once it fires, i have to keep my foot on the gas and vary the rpms, or it will die immediately. is there a way to avoid this startup procedure, but without using a IAC or similar valve, so that i can just crank it over and it will idle? i dont really care if it idles really high or low during the warmup period, i just want to avoid what im doing now.

i hope this all makes sense

thank you,
Jason

PSIG · Post by **PSIG** » Sat May 27, 2006 5:46 am

87, all you need is more air on startup. This can be done by many means from removing a plug in a hose to the manifold to a manually switched FIdle valve, to the common Bosch idle valve setup listed in the manual. Almost any controlled air leak will do

87_7MGTE · Post by **87_7MGTE** » Sat May 27, 2006 4:57 pm

right. i know if i get more air with a valve it will help. i was wondering if there was a way around that though, without the use of a valve?

if not, i may just have to do it the way you mentioned, PSIG.

also PSIG, could you point me to the page that you mentioned above? thank you.

PSIG · Post by **PSIG** » Sat May 27, 2006 7:11 pm

The 'basic' idle control page for v3.0 boards is here: http://www.megamanual.com/v22manual/mwire.htm#idle although it seems you have to scroll down quite a bit to actually get to the Fast Idle Valve section.

Another possibility is using spark advance to raise your idle, however, there may be issues with getting enough initial rpm's for the combination of ASE and spark advance to reliably get smooth starts without at least a little initial help from the gas pedal. Then, drivability would likely be impaired by the additional advance.

Rigging a simple FIdle system is so easy I wouldn't avoid doing it. The Bosch idle regulator valves are about $5 at the boneyards around here so it's not worth the hassle for me anyway. You don't even have to run power to them, although they take longer to close just sitting on top the engine soaking up heat. You can temporarily adjust any valve's flow by pinching the hose shut with an object pressed into it by a hose or cable clamp.

If you do experiment successfully with a different idle-up scheme, please let us know so it can be referenced here or in the manual for future users.

CHB · Post by **CHB** » Sun Jun 18, 2006 8:13 pm

Bosch Auxilary air regulator is completely indepedant from MS isn't it? cos refering to this diagram in http://www.megamanual.com/v22manual/mwire.htm#idle, we only run a switched +12V to it and it is all on his own.. i'm thinking of this issue too..[/img]

16FW · Post by **16FW** » Mon Jun 19, 2006 4:31 am

The part number for a JC Whitney fast idle valve isn't a good number.

What Fidle valve are most people with MS-I using?

16FW · Post by **16FW** » Mon Jun 19, 2006 5:19 am

The NAPA Fidle solenoid part number is bad as well.

Could someone update the Fidle section of the MS-I 2.2 manual? http://www.megamanual.com/v22manual/mwire.htm#idle

16FW · Post by **16FW** » Mon Jun 19, 2006 5:35 am

FWIW, I just ordered a McMaster Carr valve.

Polypropylene Solenoid Valve, Wire Leads, 1/8" NPT Female, 30 PSI, 12 VDC, Part # 7877K613, $21.74

I will let you know how it works out.

PSIG · Post by **PSIG** » Mon Jun 19, 2006 12:27 pm

CHB wrote:Bosch Auxilary air regulator is completely indepedant from MS isn't it? [clip] we only run a switched +12V to it and it is all on his own.. i'm thinking of this issue too...

Correct - there is no connection to MS at all as it is only a bimetal spring valve. As simple as it gets. As I said, you don't even have to connect the two 12v wires, but the heater power does tend to make the idle-down quicker and more consistent.