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420A Throttle Body

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Mr Ortiz

Proven Member
42
5
Jun 23, 2019
Hustontown, Pennsylvania
I took off three lines on the upper intake manifold. All the three lines were right together going outward separate ways but I can’t find the third one in the middle of them all. I have no idea what kind of line it is or what but all I know is where it’s off at sucks in a lot of air. If I could find what the other end goes to or how to find it or any info would be great. I’ve changed my plugs and plug wires today because it was acting up very bad it runs a little better but doesn’t wanna stay running. Putting new throttle body gasket on tomorrow along with tps too. But most importantly I need that vacuum line on first.
-420A engine 2.0Lt Non-Turbo
-1998 Mistubishi Eclipse Gs
-Engine made by Chrysler
 
There are only two vacuum lines connected to the intake manifold. Mine has a cap on the third nipple.

Here's a diagram of the vacuum lines connected to the intake:

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There are only two vacuum lines connected to the intake manifold. Mine has a cap on the third nipple.

Here's a diagram of the vacuum lines connected to the intake:

You must be logged in to view this image or video.
Incorrect, there are three. Four if you count the one on the TB. The one from the TB goes directly to the EVAP purge solenoid. The one on the right side of the three cluster goes directly to the egr valve. The middle and left ones can easiy be followed down by the firewall.

Somehow that diagram is missing a hose...

And of yours is capped off then maybe somebody removed it
 
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Incorrect, there are three. Four if you count the one on the TB. The one from the TB goes directly to the EVAP purge solenoid. The one on the right side of the three cluster goes directly to the egr valve. The middle and left ones can easiy be followed down by the firewall.

I don't have cruise control, so that might be why mine is capped off?

This diagram isn't that great, but it looks like there are three lines coming from the intake to the fuel pressure regulator, EGR transducer, and vehicle speed control reservoir.
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I don't have cruise control, so that might be why mine is capped off?

Yes, the middle line is for cruise control operation . If you don't have cruise, that is why it's blocked.

Post pics of what line is leaking and where it runs to as best you can. Not all super close ups, some pulled back shots so we can see what's going on.
 
Alright I’ll look. I put new plugs and wires on it yesterday and the throttle is still really acting up doesn’t wanna stay running.

I think you have something else going on with your car. A vacuum leak on these motors will cause a high idle, but the car will not run bad or stall. The 420a doesn't use a MAF sensor to determine fueling.
 
I think you have something else going on with your car. A vacuum leak on these motors will cause a high idle, but the car will not run bad or stall. The 420a doesn't use a MAF sensor to determine fueling.
Yeah as of right now the throttle body gasket is off and I have a bad plug to the throttle positioning sensor. I’m gonna be putting the gasket on soon and the plug later since autozone has to freaking order everything in.
 
Yeah as of right now the throttle body gasket is off and I have a bad plug to the throttle positioning sensor. I’m gonna be putting the gasket on soon and the plug later since autozone has to freaking order everything in.
Have you conducted a compression test lately?
 
No. Right now I’m trying to find a vacuum line that fell off in the bay behind the engine. It goes on where my finger is. Do you know where it runs too or any tips?
Yes. That is for the cruise control.

Did you not look for it when it fell off?LOL

It should still be dangling around there somewhere, look underneath the car
 
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Yeah we got it now I found that the o2 sensor plug got caught in the belt and got chewed up. Is that why the throttle is so messed up and don’t wanna keep started?
The O2 sensor shouldn't keep the car from running. If anything, it would just make it run super rich or super lean.
 
The O2 sensor shouldn't keep the car from running. If anything, it would just make it run super rich or super lean.
The O2 sensor shouldn't keep the car from running. If anything, it would just make it run super rich or super lean.[/QU
The O2 sensor shouldn't keep the car from running. If anything, it would just make it run super rich or super lean.
Well I had cut off both plugs and wired them directly with wire clamps and it don’t wanna start at all now not even a kick.
 
I took off three lines on the upper intake manifold. All the three lines were right together going outward separate ways but I can’t find the third one in the middle of them all. I have no idea what kind of line it is or what but all I know is where it’s off at sucks in a lot of air. If I could find what the other end goes to or how to find it or any info would be great. I’ve changed my plugs and plug wires today because it was acting up very bad it runs a little better but doesn’t wanna stay running. Putting new throttle body gasket on tomorrow along with tps too. But most importantly I need that vacuum line on first.
-420A engine 2.0Lt Non-Turbo
-1998 Mistubishi Eclipse Gs
-Engine made by Chrysler
I have for sale
 
I have for sale
As of now I’m trying to diagnose a major problem with the car. It does not want to start at all there’s no spark to the plugs. All the symptoms point to a bad cam positioning sensor but I don’t have the money or time to guess and buy parts. It needs to be running in the next few days. And I haven’t been able to get it running I’m screwed.
 
@Mr Ortiz Hey man, I hope you're enjoying your new SRT4! Im still sad that you had to give up on the Eclipse, but sometimes hard decisions have to be made. And this time I hope it paid off! Just know that the forums will always be here for you, I will always be here too :D. If you ever pick up another DSM, please come back by.
 
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