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Discussion Starter · #1 · (Edited)
As most of you know, I bought a 89 CSX that has sat for 9 years. I would like to verify VNT is moving and not seized up. Car has brake issues along with CV joint issues, so driving it is really not an option.

Can I reach down and try actuating the VNT by hand (obviously engine off and cool) and if I can, would I be trying to pull up on the actuator rod, or push down not eh actuator rod?

Or should I try moving them with a vacuum pump?
 

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I do not think there is a way to actually test the turbo itself while in the car other than driving, you will not be able to actually see the vanes moving inside the housing.
I have never really gotten into the turbo itself and where vacuum/pressure would be applied/released to open/close the vanes under different driving conditions, I have only diagnosed the VNT system on my car when there was an issue, either a VNT Solenoid code or an overboost condition.
You should not have to go far or fast to check boost, the VNT spools very quickly, virtually no lag, according to Chrysler you should hit full boost from a standing start in 2.3 seconds (less than 100', my 60' times were in the 2.20 range.)
The only thing you will not know until you can drive the car is how the turbo/turbo system reacts under high load/rpm situations, weather there may be a lack of boost or an overboost condition.
If you have access to a scanner you can actuate all of the VNT solenoids.

Turbo Database - The Hard Parts, #12 VNT Pictorial Breakdown.

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Discussion Starter · #4 ·
So I took 102 out for a quick first drive and it builds over 10#s so assuming the actuator and vanes are fine. However boy did this sucker ping bad under full throttle and high boost. Car has 93 octane in it and a 255 fuel pump with new filter as well. Tomorrow I plan to check the base timing to make sure previous owner does not have it set too far advanced. Earlier today I spray carb and choke cleaner around all the vacuum lines and there was no increase in RPMs, so, but the tach says its idling mourned 1,100 rpms.

Other than that, well that and four flat spotted tires and clicking passenger side cv joint (replaced drivers side today and passenger side is due in on Tuesday), it seems to run ok. Need to look into the HVAC vacuum controls some more as the switch will blow air everywhere except panel. Oh well, I am slowly chipping away at it.
 

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1989 Dodge Shadow 2.5 non turbo 3 speed automatic
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Need to look into the HVAC vacuum controls some more as the switch will blow air everywhere except panel. Oh well, I am slowly chipping away at it.
Hopefully you have better luck than I had. I got the box all the way out and apart as my a/c condenser had a hole in it. Got it all back together with new foam, made sure all the vacuum actuators worked, and re lubed every thing. I also hade the same problem before I pulled the box where I only got floor and defrost. After having the box out I found out that the foot to face baffle are 2 pieces that are on a plastic shaft and the face part is only connected by a small U shaped piece of plastic. It was snapped off so we tried to fix it. It lasted a few cycles then broke again. I ended up sewing the 2 parts together with fishing line while it was in the car. (Not fun)
 

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You should never have heard any detonation if the knock sensor circuit was working properly.
Do you have access to a scanner to look at Knock Retard and Total Spark Advance?
Is this car equipped with an EGR system?
Do any plugs have deposit fouling?
What is your MAP sensor voltage compared to vacuum/pressure at the time you hear detonation?
 

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Discussion Starter · #7 · (Edited)
You should never have heard any detonation if the knock sensor circuit was working properly.
Do you have access to a scanner to look at Knock Retard and Total Spark Advance?
Is this car equipped with an EGR system?
Do any plugs have deposit fouling?
What is your MAP sensor voltage compared to vacuum/pressure at the time you hear detonation?
No scanner, new plugs, and I have a new spare knock sensor i am going to install. Notnsure about the EGR.

Oh, if you touch the fuel injection harness around #3 injector, the engine stumbles and fault 27 came back. I will have to dig into that harness/connector. .

As for the HVAC, it was simply the vaccum line by the battery to the HVAC controller the rubber was so lose on the hard plastic line that it was just sucking air and not enough vacuum to the HVAC controller. So that one is fixed.
 

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Discussion Starter · #8 ·
Anyone know how far the VNT actuator arm actually moves? With engine at idle and when I disconnect the vacuum line from the actuator can my arm moves MAYBE 1/4". Seems pretty dang small to me.
 
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