Car will not idle

F

fvkagi

Member
Hello all! I bought this ST185 in the winter non-running and I have been trying to fix it over the summer. I am having this weird issue where the car will not idle but it seems to run if I keep it alive using the throttle. I also read the codes and I have a code 51. The car will not even start unless I give it a little throttle during start up. I recorded some videos of the car and I was wondering if anybody has an idea of what going on, or things I should be looking at. Thanks for the help in advance!

Starting without touching the gas - https://youtu.be/fq9UesIioA8
Starting by giving it a little gas (then letting off) - https://youtu.be/hXKK3CvQgE4
 
S

sefiroxx

New member
Clean throttle body/butterfly

Then start with minimum air stop screw and tps testting.

As well, check the isc (idle speed control) valve that is used to allow air around the butterfly when it is closed.
 
F

fvkagi

Member
Ooh I will check all of this on the car tomorrow, I will update what I find. Thank you everybody for the help!
 
F

fvkagi

Member
Billythebest":14gtlcw6 said:
Anyluck??
Click to expand...
I was messing around and the car will now start without touching the gas pedal. It goes to like 2k rpm then stalls in like ~5 seconds. So it's better! Is the isc the thing with the plastic screw and spring coming off the side of it? Thanks for the help!!
 
S

sefiroxx

New member
Something like this.

Has internal spring to rest the valve. Water flow to open when cold and close when warm. Solenoid to override and provide feedback on position.
23a31427849c6abf496b1fe2abad5f6f.jpg
 
F

fvkagi

Member
sefiroxx":18jsgq6b said:
Something like this.

Has internal spring to rest the valve. Water flow to open when cold and close when warm. Solenoid to override and provide feedback on position.
23a31427849c6abf496b1fe2abad5f6f.jpg
Click to expand...

My radiator was leaking, and I recently fixed it. If the coolant is low, will it mess up the isc valve or is it mostly electronic? Thanks for the help!
 
F

fvkagi

Member
underscore":113nhuhq said:
Have you done the usual checks for boost/vacuum leaks?
Click to expand...

I looked for a while and I did not find anything obvious. I am not too familiar with the 3sgte so I might have missed something... I also cant hear any leaks because its an open downpipe haha

I did find a tear in the intake after the MAF, so I fixed that and it made it a bit better.
 
underscore

underscore

Well-known member
The best way is to make a boost leak tester so you can do it with the engine off. There are a lot of lines tucked into tight places so it's hard to check them with the engine on.

Also pull the EFI fuse to reset the ECU every time you fix something so it's not trying to run with any bad habits it may have learned when things were broken.
 
F

fvkagi

Member
underscore":3tv6b5sc said:
The best way is to make a boost leak tester so you can do it with the engine off. There are a lot of lines tucked into tight places so it's hard to check them with the engine on.

Also pull the EFI fuse to reset the ECU every time you fix something so it's not trying to run with any bad habits it may have learned when things were broken.
Click to expand...
After an hour of wandering around Lowes I have created a boost leak tester for $10 :)
I will find out tomorrow whether it works or not haha
 

Attachments

  • ALLTRAC TESTER.jpg
    ALLTRAC TESTER.jpg
    103.6 KB · Views: 1,938
F

fvkagi

Member
underscore":1e49vv8i said:
Looks a lot like the one I made! Don't forget to wedge the throttle open with a screwdriver.
Click to expand...
What did you set the psi to on the compressor? I was going to do like 10 maybe
 
underscore

underscore

Well-known member
Start low, but I went to about 20 since I was planning to run 16 and didn't want anything suddenly failing if I overboosted a little.
 
F

fvkagi

Member
Ok, sorry for the delay, my friend needed help with his Miata haha

Anyways, I ran the boost leak tester and found a few loose hose clamps that I've fixed but I also found a leak on the throttle body gasket, so I ordered a new one of those. Just tightening the hose clamps made the car run better, it will idle for about ~20 seconds on its own now! Getting there!

Updated idle video: https://www.youtube.com/watch?v=jYKdgMUDItE
 
You must log in or register to reply here.
Top