1G What is this noise!?

[TheKingJames1994]

1991 Eclipse GS-T manual trans. Has sat in a barn for about 20 years. It won't turn over, and with key in the on position it's making this noise. I can't tell where it is coming from. But sounds like possibly starter. I felt the starter and all around the area checking for vibration but can't feel anything

You must be logged in to view this image or video.

 

[TerminalTalon]

Use a long piece of metal or screwdriver and listen to everything in that area if you don’t have a stethoscope.

Sounds louder when near the throttle body are but if it’s louder near the starter I would point there. Also change that battery or deep cycle it. Weird voltages can cause a lot of issues.

 

[DSMPT]

Sounds more like from the ISC. Try to disconnect the connector in the green circle below and see if it stops, if it stops then the sound is from the ISC. You stated that your car is 91 but that throttle body is from a 90. Maybe your car is 90?

Edit: I could see the cruise control pump position in the video. I think your car is 90.

You must be logged in to view this image or video.

 

[99dsmer4g63]

Yeah sounds like the iac trying to step itself to find its home before start up. I say trying because it’s not.

It should be an audible clicking noise that stops after 5 seconds or less. I would pull the iac and hook it up to 5v camera battery and see if it steps after cleaning.

You may want to pull the ecu and inspect the sensor ground too.

-Daniel

 

[steve]

Edit: I could see the cruise control pump position in the video. I think your car is 90.

Looks that way to me too.

First thing I'd do is pull the ECU for an inspection. '90 ECUs have a tendency to burn up when the caps leak and the odds are really good that the caps have leaked if it's sitting for 20 years in a barn.

 

[TheKingJames1994]

Sounds more like from the ISC. Try to disconnect the connector in the green circle below and see if it stops, if it stops then the sound is from the ISC. You stated that your car is 91 but that throttle body is from a 90. Maybe your car is 90?

Edit: I could see the cruise control pump position in the video. I think your car is 90.

You must be logged in to view this image or video.

Hey sorry it took me a while to get back on here. I was busy with work. You are correct. I unplugged that and the noise went away. Also checked the title again. It is a 1990.

What does ISC stand for? And do I just need to replace it?

Also I finally got the starter to engage. The signal wire was broken. But it just clunks like it's engaging the flywheel but then the car doesn't turn over.

Could that also be ISC related?

 

[steve]

Hey sorry it took me a while to get back on here. I was busy with work. You are correct. I unplugged that and the noise went away. Also checked the title again. It is a 1990.

What does ISC stand for? And do I just need to replace it?

Also I finally got the starter to engage. The signal wire was broken. But it just clunks like it's engaging the flywheel but then the car doesn't turn over.

Could that also be ISC related?

Idle Speed Control Servo.

So the engine doesn't rotate when you get the starter to engage?

Not ISC related.

Have you checked that the ECU is running yet?

You must be logged in to view this image or video.

 

[TheKingJames1994]

Thank you for that diagram. Yes the starter engages but motor does not turn over. I have not checked the ecu. What do I need to do to check it?

 

[steve]

When you turn the ignition on the CEL should turn on for about 5 seconds and then turn off.
When you turn the ignition on the the Boost Gauge should move to the 0 location and stay there until you start cranking.
When you turn the ignition on the diagnostic port pins 1 and 12 should start pulsing 12v on for 1 second off for 1 second repeated (heartbeat). If it doesn't do anything or has a constant 12v across the two pins the ECU is damaged. The other option is that it will start pulsing out any stored error codes instead of the heartbeat.

You must be logged in to view this image or video.

Make sure you can turn the crank by hand using the crankshaft bolt. If you can but the starter won't you may not have a good connection to the main power line from the battery to the starter.

 

[TheKingJames1994]

Hey, sorry it's been so long. It's an outside project and it's cold here in the winter I'm back to it though.

I checked the voltage across those pins you told me. It's staying at a steady 7.65 volts. No pulse.

I tried to crank over the engine by hand. It moves free a little ways in either direction then stops. I tried with a breaker bar to move it more forward in the clockwise rotation because I assume that's correct? But wouldn't budge. I could have applied more force, but wasn't sure how hard i should go or if that is for sure the right rotation direction. I will attach a video of turning the crank.

And also a picture of the spark plugs I removed. 2 were fine. 2 were crushed. But the two that were broke gave me a lot of resistance coming out so I'm not sure if they broke coming out from being seized, or if something internally broke them. I'm hoping through the attached Pic you guys can shed some insight and point me towards next steps. Thanks!

You must be logged in to view this image or video.

You must be logged in to view this image or video.

 

[steve]

You must be logged in to view this image or video.

That's what happens when something breaks off in the combustion chamber and bounces around.
You can't turn the engine any farther because the pistons are likely hitting the valves.

I checked the voltage across those pins you told me. It's staying at a steady 7.65 volts. No pulse.

No pulse and low voltage either point to a dead battery or dead ECU, possibly both.

 

[TheKingJames1994]

So i guess now we know why it sat in a barn for 20 years you think the piston rings broke or something?

 

[steve]

So i guess now we know why it sat in a barn for 20 years you think the piston rings broke or something?

No more likely the timing belt failed and the valves and pistons collided. Sadly very common for DSM's that haven't been maintained properly. Did the engine turn over back in August? If so this was caused since.

 

[TheKingJames1994]

Ahh I see. No, it's never turned over for me. The person I got it from said it had been sitting in a barn for 20 years. And didn't know much about it as it was an estate sale. It took me a while to even get it to try and turn over. The starter had wires broke going to it. I fixed those then the starter acted like it tried to engage but wouldn't turn the motor. Then today I finally checked those pins you suggested and tried to hand crank the motor and removed the spark plugs and that's what I found. Would you say the ecm is also fried since it's getting constant 7.65 volts on those pins?

 

[steve]

We differentiate between the engine cranking/turning over and starting/running. So to be clear the engine never cranked at all? The starter spun but didn't engage with the flywheel? Either way the signs are the valves has crashed or worse.

Without knowing what the battery voltage is/was I can't say but the odds are high that a 91 ECU has had the capacitors leak. The only way to know for sure it to pull it, open the case and and look. (take pictures if you need people to look over your shoulder)

 

[TheKingJames1994]

Okay. I just went and hand cranked the engine counter clockwise a couple inches to see if the starter is in fact engaging. Yes, it engages, and spins the motor forward the couple inches until it comes back to a crunching halt. Just like I couldn't spin it by hand past that point. So I'm guessing the only recourse would be a full engine rebuild?

Oh and also just to be clear. Before I mover it back a couple inches the starter didn't move it because it was already at that binding point the first time I tried to start the car.

 

[steve]

You sure it's a 91? That's a 90 throttle body on it. The started building 91's in June of 91 before that they were 90's.

 

[TheKingJames1994]

You are correct. I was mistaken in my post. It is a 1990.