The Top DSM Community on the Web

For 1990-1999 Mitsubishi Eclipse, Eagle Talon, Plymouth Laser, and Galant VR-4 Owners. Log in to remove most ads.

Please Support Fuel Injector Clinic
Please Support ExtremePSI

2G High Idle, poor/pathetic heat...

This site may earn a commission from merchant
affiliate links, including eBay, Amazon, and others.

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

dffusion20

15+ Year Contributor
91
0
Aug 24, 2007
Irmo, South_Carolina
So everytime when I go to start my car it always idles high, like 1,500 rpms. It doesn't matter if the car is warm or cold. I can be out driving the car for 30+ minutes and when I go to a red light and drop into neutral the car revs up to 1,500 rpms. On occassion it will still sit where it used to at 1100 rpms.

Now at the same time, my car is running super cold, like hardly to the 1/4 mark on the gauge. And my heat is pathetic.

Do you think that my thermostat may be stuck open? Causing it to run cool and maybe kepping the auto enrichment system on? Or choke whatever causing it to run high because it is "trying" to warm up?

Could this be related to my poor heat?

I am really at a dead end with this. I can't figure it out. Please help.
 
Well I had it adjusted and I was idleing around 1000 rpm, I then disconnected the batt to put the new turbo setup on, It was after I reconnected the battery that It started to idle high again.
 
I did a search on here and read that the sensor, not valve was located inside the maf... what to do? I also read some threads about egr valves creating some problems at idle but i dont know how this could all of a sudden be the culprit
 
You're T-stat is stuck open so the coolant can never get to operating temp.

Thus the coolant sensor is telling the ECU to keep the idle up and fuel coming in so the block can get to operating temp to bring the idle speed down.

Change out the T-stat and I think your probs will settle down.

Good luck-DSM
 
You're T-stat is stuck open so the coolant can never get to operating temp.

Thus the coolant sensor is telling the ECU to keep the idle up and fuel coming in so the block can get to operating temp to bring the idle speed down.

Change out the T-stat and I think your probs will settle down.

Good luck-DSM

i had a very similar problem, and it was the t stat, so i definitely suggest changing it (its a quick, 10 minute job minus bleeding the system...which still isn't long at all)

However - do not get the t stat from autozone/advance etc, and make sure you get oem, unless you are in a hurry to get your car back on the road and want to order an oem one to do later. I replaced mine with an autozone one, and within a couple months i was having the exact same problem, so i ordered an oem one through extremepsi, and have been running it with no problem for a while now.
 
Sweet I appreciate it gents....:) Could that have anything to do with my pathetic heat?

yes, the heat inside is directly related to the heat of your engine.

it is engine coolant that's flowing through your heater core.
 
Sweet I appreciate it gents....:) Could that have anything to do with my pathetic heat?

It's the same issue. The "IAT valve" is really an "FIAV" (fast idle air valve). The IAT is an Intake Air Temp sensor, and it is in the MAF. The FIAV is in the throttle body, and has coolant flowing through it. If the coolant never heats-up, the valve never closes, and your idle stays high.

Go to mitsubishi, and give 'em $20. They'll give you a legit thermostat, with a new gasket. Then use a turkey-baster with a little (10 or 12") 1/4-3/8 " hose on the end to suck coolant out of the cap. The hose lets you suck from up inside the top of the radiator. Squirt the coolant into a clean, empty water bottle, or two. With the coolant off of it, you can see the thermostat through the filler. When coolant stops seeping up over the thermostat ( maybe a qt., or two ), quit sucking and unbolt the cover. Scrape the surfaces clean, wipe them dry, throw it all back together, and pour the coolant back in. That's my cliff's-notes version of the procedure. You can either start the car before pouring the coolant back in, or just dump the extra in the overflow tank.

If you have an OEM radiator that still has the little drain hose sticking through the splash shield, then it's easy enough to just drain a few qts. into a gallon jug to do the job. My 92 has an aftermarket Al radiator with an allen-head drain plug: way messy to drain. Most 1Gs are pretty old to still have their original radiator. Your choice.
 
Thank you 1990AWD and Brownfinger... I will purchase a new thermostat this upcoming week.. I am good on your cliff note version until you say..

"You can either start the car before pouring the coolant back in, or just dump the extra in the overflow tank."

Wouldnt I just go ahead and fill it back up when the new t stat is in? What is the significance of starting the car before I put the fluid I took out back in? not trying to sound dumb I just havent ever done it
 
If you start the car it lets you get all the air bubbles out of the system just let it idle as you pour it in just don't puch it because it'll fly back out... but just idling will let you get the air out or like said before dump the extra in the reservoir and it'll get sucked back in slowly. works well either way :thumb:
 
So the new t stat is in and it did fix my temp problem but we knew that would happen LOL

The car is still idling high sometimes. The weird part is that it is never consistant. I can be driving, put the clutch in and the car will rev to 1750 and hold for a while, then it might drop back to 1000 and do it again. The car will rev itself if you roll 2mph if that helps.

As I was pulling in to my driveway earlier, it was acting fine, I would put the clutch in and it would jump maybe 100 rpms...

Any suggestions?
 
throttle cable sticking/not letting the plate close? i know i my celica when i first got it the previous owner messed with it, and i had to adjust it a little bit. and for a 1700rpm idle, it wouldnt have to be open much for it to be the cause.
 
Alright cools, I will look into that. Now with exams finally being done I have some more time to actually look onto this. I read a couple diff threads about t body cable sticking and removing the cc so I will keep you posted.
 
Do you have anything like a logger to see if your o2 voltage is cycling? When the car is moving and the throttle is closed the idle gets bumped. If the o2 signal doesn't cycle then it will try to rev itself too much causing idle surge. Just something to look into...
 
huh.. interesting. I do not, I was planning on getting link in the future and injectors so I could save some money instead of getting pocket loggers and smaller stair stepping mods... Ill see if I could maybe find a friend with one. Good suggestion!
 
Support Vendors who Support the DSM Community
Boosted Fabrication ECM Tuning ExtremePSI Fuel Injector Clinic Innovation Products Jacks Transmissions JNZ Tuning Kiggly Racing Morrison Fabrications MyMitsubishiStore.com RixRacing RockAuto RTM Racing STM Tuned

Latest posts

Build Thread Updates

Vendor Updates

Latest Classifieds

Back
Top