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rain, no idle

2.3K views 42 replies 8 participants last post by  3kGaTech  
#1 ·
i know i've seen this somewhere on the board, but i tried a search and couldn't find anything on it...

i was driving to a friend's house and it was torrential rain... i made a point to avoid ALL puddles, which i'm pretty sure i did. but my car now has just about no idle. when i take it out of gear, it dies. but it stays on as long as i rev it when i'm at a stand still/out of gear/neutral.


what's goin on ?
 
#2 ·
Does this continue, even now that the rain has come and gone? If not, I would definately say its an ignition problem. If so, I would still say its an ignition problem, but its a bit harder to diagnose. Was the engine skipping when you revved it in the rain?

-- Henry
 
#4 ·
Well thats convineint. Does it skip?

Might want to try having somebody sit in the car revving it, wihle you pull spark plug wires and see if they arc to the plenum.

-- Henry
 
#5 ·
If the car doesn't miss or run rough at higher RPM's I'm having a hard time understanding how it would be ignition.

BTW - I wash my engine compartment with a power sprayer once a month (followed by WD40 on any fittings / bolts) and have never had any trouble with puddles. Water is not the problem, water + salt is a big problem.

If the engine is pretty grimy, you might want to go on the offensive and wash it.



Clint
 
#7 ·
check all the lines on your throttle body, my guess is that you have some type of vacuum leak somewhere.
 
#8 ·
Advise if turning on A/C with temp set to 65 degrees keeps it from stalling. (Rain may be a red herring.)



Clint
 
#9 ·
ShaRd ,
Im wondering if youve ever fixed this problem. If so, how did you do it?
I seem to be having the same problem with the idle. It was running rough at some higher RPMs also but I since changed plugs and wires and cleaned out the Intake Plenom so no more rough high RPM, but still no idle.
Any ideas? What worked for you?
 
#10 ·
not yet. i'm taking it to the dodge center tommorow to get it looked at . they said it might be the throttle body needing to be cleaned, and a good mechanic friend of mine said it might be the fuel filter (clogged, so the only way to push fuel through to the engine is to give it gas, which explains the no idle unless giving it gas)

i'm going to tell them to take a look at the fuel filter while they're in there tommorow. i'll tell you guys what happens
 
#11 ·
I just got back home and got my car working fine....for now at least.
I did alot of research on 3si and saw people talking about similar problems and most pointed to worn out and dirty parts. I figured if thats the case than let me clean everything I can and replace anything that cant be cleaned. So let me tell you what did it for me...so far.
Once again, I changed all plugs and wires and while I was at it I cleaned the Intake Plenom (just cuz it was there and nasty looking). After which I got rid of the roughness at high RPMs but it still wouldnt hold the idle.
After that I did more research and saw that alot of people here cleaned or replaced a part that is attached to the Throttle Body. I dont remember what exactly its called and alot of people have different names for it but Ill tell you how to find it and what I did.
If you are on the passanger side of the car, facing the Intake Plenom, look at the Throttle Body. Look imediately below the TB and slightly to the rear is a small...something which is attached to the TB with 2 8mm bolts (not the 3 phillips screws that it looks like hold it there) and a wire harness. I removed the battery and the large air intake tube that is clamped onto the TB with a C-Clamp. I then remove the wiring harness and those 2 bolts and saw grimy it is in there(I used a socket wrench with a 3" or 6" extension). First I cleaned it off with Air Intake Cleaner that I bought at PepBoys. Next, while your looking into the TB you can see 2 square shaped holes facing downward. I sprayed the AirIntake Cleaner in there and saw a whole lot of grime pour out of it. When I restarted the car I left it idling for about 30 minutes because I read somewhere on 3si.org that the ECUs memory of where the idle needs to be is reset by unplugging the batt for 15 mins then idling for 10 mins.
I apologize for the lack of technical terms here but I think you can get what Im saying. Regardless of what they are called, all that worked for now. I feel alittle reluctant to post this because I only drove for about 30 minutes and I dont know if it needs more of a test before I deem in 'fixed' but I wanted to let you know before you send it to Dodge and waste some money.
Good luck and please reply with any other info you may have about this matter!
Thanx and Good Luck!!!
Isaac
 
#12 · (Edited)
Congrats, you just cleaned your IAC! (You can also disassemble it by removing the three screws and make sure the internal assembly turns freely although most of the crud is on the outside.)

Small word of caution, the manual cautions against spraying carb / TB cleaner into the two bypass ports although I have never heard of anyone report that they they damaged their FIV (fast idle valve) or IAC by doing this. Kind of a funny warning because the first thing people do when they remove the IAC is soak it with with TB / carb cleaner!



Clint
 
#13 ·
Clint,
Now your talking!!! IAC!!! I knew someone would know what Im talking about!

Last night I went for a 40 minute drive and had no problems at all, my car ran as smooth as ever. This morning I drove to the bus stop (to get to the city for work obviously) and had no problem at all and it purred like a kitten.

Since I changed the plugs and wires and did all this my car feels like it got its vigor back, I have a love for my car again!

ShaRd,
I hope you correct your problem soon and I think you should try the same as I did.

Good Luck!
 
#14 ·
ShaRd

and a good mechanic friend of mine said it might be the fuel filter (clogged, so the only way to push fuel through to the engine is to give it gas, which explains the no idle unless giving it gas)
Fiction. The primary role of the gas pedal does is to provide more air / not fuel. The ECU gets information from the MAS indicating air flow and provides an appropriate level of fuel by adjusting injector pulse width. (Technically the TPS sensor also detects changes in throttle pedal position to provide enrichment during acceleration but this is a secondary effect.)

If it idles fine with A/C on and temp set to 65, there is a good chance that you are having trouble with BISS adjustment. Old O ring is notorious for allowing the BISS to self tighten.


Clint
 
#15 ·
i never said anything about it idling fine. it -doesn't- idle at all. (except the few minutes at startup- seems to be very fickle) that's the problem

anyways i finally got it checked out by dodge and they said it was cuz of the idle speed controller (part# MD628053)

they quoted me around 400 for the part and 190 for labor... so i'm looking for the part online...

has anyone replaced one of these before? i did a search and it was mostly about people selling them/needing them, if found at all
 
#16 ·
Try turning on the A/C with temp set to 65, if it idles better there is a good chance that you are having trouble with BISS adjustment.

Otherwise try cleaning your IAC. (like the other guy in this post whos idle is now perfect!)


Clint
 
#18 ·
Theres not much to mess up. Take out the battery and the intake tubes where it meets the throttle body and theres two 8mm bolts. Take out the AIC, clean it, throw it back in, and your done! Make sure to let the car idle for at least 15 mins with no accessories on.
I wouldnt spend the $500+ without first trying that simple procedure.
Tools you need:
Socket Wrench
3" Socket extention
10mm socket
8mm socket
flat head screw driver
and something strong to clean it with.
 
#19 ·
ShaRd - This is my last atttempt at communicating a point to save you some time/money.

If the car idles better with AC enabled, it would indicate the IAC is working. If it still stalls with AC enabled it sounds like you need to clean your IAC.


Clint
 
#20 ·
Thank god somebody know how to check if that damned IAC is working.

I almost went and spent the $429.00 I got quoted on the part (at three different places. Same price) But my car only does it when it is really raining hard, or I run through a deep puddle. I'll have to copy all of this down, and then go home and give it a shot.

Its been a while since my car idled right. About 3 weeks actually. What is a SOHC supposed to idle at?
 
#21 · (Edited)
Warm idle with A/C and all lights / accessories OFF should be ~750 RPM.

Cleaning IAC is a good idea even as preventative maint. If idle speed increases when you turn on A/C it means IAC is working but may still benefit from cleaning.

If idle is low (but there are no other drivability issues) you may want to try replacing the BISS o ring - it has a bad habbit of self tightening when it gets old - lowering idle speed outside control range of IAC.


Clint
 
#22 ·
I said in a previous post that I found a love for my car again...
I think its one of those love/hate things!!!!
IT DOESNT IDLE ANYMORE!!!!
I know we've gotten a few people in on this thread so someones got to have some info! This is very weird, it worked great for 2 days....now....no idle...all of the sudden!
Once again, I changed spark plugs, wires, cleaned the IAC and the intake upper plenom.
Please give me some ideas here! PLEASE!
 
#23 · (Edited)
Scientific approach would be to put a logger on your car to find out what is going on with your IAC count. If you don't have a logger, try 2 turns counter-clockwise on BISS. (Screw is under rubber grommet on front of throttle body.) If that fixes it, buy a new o ring for the BISS screw.


Clint
 
#24 ·
The BISS??? Is that the screw that looks like it would be the idle screw? Kinda facing at you when your looking at the throttle body?
 
#25 ·
yep - Controls air bypass volume.
 
#26 ·
cbatters,
I turned it about 2 revolutions counter clockwise and it is now holding an idle at about 400-450RPM, obviously too low.
Your saying this means I should change the O-Ring for the BISS screw?
Why wouldnt I just turn it alittle more till the car idles at around 700RPM then leave it? Will the O-Ring only deteriorate more? Is the engine now not getting the proper air/fuel mixture?
Where can I find directions for changing the O-Ring?

I know I have lots of questions but I really appreciate your help!!!!