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Idle surge & WTB Parts for 1G DSM

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925BoostKid

Probationary Member
14
0
Feb 15, 2014
San Ramon, California
New on here. Had a few things to discuss:

First, I have a surge in my idle. During cold starts, and also when I come to a stop. The surge when it's cold last until my Dsm is warmed up. The surge occurring when stopping only last a second or two then the idle becomes normal. Any help or tips on where to start?

Second, I'm in the market for chrome GST wheels! Let me know! Located in the Bay Area!

Thanks,
Chris
 
1g dsm have whats known as dsm idle due to a thermo valve in the throttle body that opens or closes due to coolant temp to controll cold idle this valve is works simular to a thermostat it is not electronis but after time this valve can not work properly and alowe too much air in and cause a surge there are many ways to repair this but it the easiest is to remove the throttle body and remove the drilling plug (looks simular to a freez plug) and take needle nose plires and screw the seat in till it bottoms out reinstall plug and reinstall throttle body
 
1g dsm's have what's known as dsm idle due to the fast idle air valve(FIAV) in the throttle body that opens or closes depending on coolant temperature to control cold idle. This valve works similar to a thermostat, it is not electronic but after time the spring in this valve becomes old and worn and will allow too much air to directly bypass the throttle, thus causing an idle surge.
There are many ways to repair this, one of which is to buy a FIAV bypass plate. The easiest and cheapest way is to remove the throttle body, remove the drilling plug (looks similar to a freeze plug) and take needle nose pliers and rotate the valve clockwise until it closes completely. Reinstall the plug and install the throttle body.

Cleaned that up a bit for you.

Yes this one of the many things that could be associated with a fast or surging idle, however the link I provided covered not only this issue but many of the others as well.

Also, if you do this free FIAV bypass, disconnect the coolant lines from the TB, and loop the lines or cap it at the source. They are not needed and could increase intake temperature rather than decrease it.
 
I took a look at the link you provided me and took action on one of the first test. While surging I when to my exhaust pipe to smell some of the fumes that were coming from the pipe and noticed it strongly smelled like unburnt fuel. Thus with these findings according to the link you provided I have reason to believe the 02 sensors may be bad. Should I look into the FIAV bypass first or replace 02 sensors based on my findings. Thanks for all the help everyone!
 
I was having the same symptons you are describing. Starts during a cold morning would usally net me an idle of around 1500 if not higher, after driving and coming to a stop it would fluctuate from around 700-1200 a few times and than idle normally.

My car has new intake and throttle body gaskets, as well as a full vacuum and egr delete so I eliminated a few of those as the culprut and went ahead with the FIAV bypass, which solved my problem completely.

It is said that some have issues starting their car during the cold after doing the bypass, more-so with the true block off plate. I however have not had any starting issues and I see temps in the low 10's some mornings.

You might try verifying some of the simpler things in that link I posted such as the throttle body gasket or vacuum lines before buying a new o2 or moving forward with the bypass.

A bad o2 will generally(but not always) affect the car during driving, not just at idle.

Here is a link for the free FIAV block, but if you feel the need to order the nice shiny plate, make sure you get the bypass, not the block off plate.

http://dsmtuners.com/forums/articles-intake-exhaust/391977-free-fiav-block.html
 
Cleaned that up a bit for you.

Yes this one of the many things that could be associated with a fast or surging idle, however the link I provided covered not only this issue but many of the others as well.

Also, if you do this free FIAV bypass, disconnect the coolant lines from the TB, and loop the lines or cap it at the source. They are not needed and could increase intake temperature rather than decrease it.
thanks for the clean up im just a redneck LOL so grammer is not my strong point, and oh yea the coolant lines forgot to include that
 
i tried to check my isc connector resistance, but i didn't get any readings, although my car does idle a little better since i unplugged it and plugged it back in. y am i not getting readings?
 
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