Help, Multiple Problems...

[Spoolin98]

Hey guys I need some help getting my brothers car running right. To make a long story short, he bought a 91 talon tsi awd not knowing that the axle bracket bolts were snapped off inside the block. I ended up pulling the motor to extract the bolts. I replaced the intake manifold gasket because there was a huge vacuum leak. I dropped the motor back in and ran into a few problems.

#1
The CEL is on only at idle, when you give it throttle it turns off. Anyone have this same problem? How did you fix it? I am not around the car. I'm away at school.
My brother bought a datalogger, but cannot seem to get the thing to work. First the software sent by pocketlogger was faulty, now he got the software working, but the palm keeps telling him to check the connection. He followed vfaq for the installation of the logger cable.

#2
The temp gauge does not work since I reinstalled everything. I took the car to autozone, the guy there said he knew a bit about dsms, he looked at the car and said it had a 2g thermostat housing, and the person bent these pins to fit this female connector on (attached pictures). It looks like the part being pointed to has been replaced, there is some sort of sealant around it, the grey stuff. Is this a 2g housing? I dont understand why it is not working now, because it was working before.

#3
The car stutters around mid range rpms. The only thing I touched were spark plugs, wires, and the coilpack(which was swapped onto another IM). I gapped and put new plugs in, that did not fix it. The car did not do this before I pulled the motor. I did a boost leak test, it seems the only place there is a leak is the throttle body seals, which explains why I need the BISS screw all the way in to get the car to idle correctly.

Sorry for the long post. I just want to get this car running right already.
Thanks in advance.

 

[ddavisaf]

Not exactly. For the car to stumble, there has to be a problem. What year car is this?

 

[Spoolin98]

91 Talon TSI AWD

 

[ddavisaf]

Primary resistance .77 to .95 Ohms
Secondary resistance 10.3K to 13.9K Ohms for the coil pack
Insulation resistance more than 10M Ohms.

This is via the Hayne's Manual. I don't have my Chilton's or my FSM with me right now.

 

[ddavisaf]

Just remember. When it deals with electronics, they just go bad. No rhyme or reason. They simply hate human beings it seems.

 

[ddavisaf]

Okay, so without the trouble code, and without the TB seals being replaced and the coils being tested that's all we can do for this problem. On to the thermostat housing issue.

2G t-housings have 2 plugs.
1G t-housings have 3.

You have...
C. Coolant temperature sending unit
B. Coolant temperature sensor (ECM)
A. Coolant temperature switch (A/C)

According to the picture above.

C. is a plug
B. is a plug for 2 male spade connectors, one facing horizontal the other verticle
A. is a single female spade connector

Which plug exactly is the one you're having trouble with. (I'm sorry for all this back tracking. It's just easier this way)

 

[Spoolin98]

Ill have my brother check the resistance. So that means the coils can be bad and the car will still run?

 

[ddavisaf]

Ill have my brother check the resistance. So that means the coils can be bad and the car will still run?

More or less yes.

 

[ddavisaf]

BTW, you've tested the gauge itself correct? This is easily done by grounding the connector. It will cause the gauge to read hot.

 

[Spoolin98]

This is where it gets confusing. If you look real close at the pictures, I only have 2 plugs that I can see. One that is a 2 males in the shape of a T, a big rubber connector goes over that one. The other connector is 2 males parrallel to each other, but they are bent together to fit one single female connector over them. If you look at the pictures there is residue from some sort of sealant around the sensors, they look like they have been replaced before. At the bottom of the thermostat housing, there is a yellowish brown sensor? With vacum lines connected to it.

 

[Spoolin98]

BTW, you've tested the gauge itself correct? This is easily done by grounding the connector. It will cause the gauge to read hot.

No I have not done that, I will have my brother do that also. It worked before I pulled the motor so I dont think that is it, but I'll have him check anyways.

 

[ddavisaf]

Ha ha... it's making sense now...
Yes, your sensors are switched around....

 

[ddavisaf]

Okay.
Here is what you have....
Yellow-Coolant Temperature Sensor (ECM) 1G
Blue-Coolant Temperature Sensor (ECM) 2G
Green-Some weird vaccum line connection

Here is what it should be...
Yellow-Coolant temperature switch (A/C)
Blue-Coolant Temperature Sensor (ECM)
Green-Coolant temperature sending unit

 

[Spoolin98]

#1 is the 2 bent prongs that I have a female connector on. They should be like this l l but they are bent like a V.

#2 Is the thing with the vacuum lines?

#3 Is the 1 horizontal male and 1 vertical male, T, with a rubber fitting that goes over it.

 

[ddavisaf]

There should not be anything with vaccum lines connected to the cooling system. It's a closed system.

 

[Spoolin98]

So how was all this working correctly before? This is mind boggling...
So the coolant temperature switch a/c should be all the way up top?
What do you mean it should not be there? Then why is it? This is hilarious.
So if there should not be vacuum lines connected there, what should be? Where do the vacuum lines belong?

 

[DSM90AWD]

Green-Some weird vaccum line connection

That's the EGR's Thermo-valve. One nipple connects to one of the TB ports that leads to the back of the throttle plate, the other to a port at the front of the throttle plate. Both connect to the EGR valve. When cold the thermo-valve is open so no vacume reaches the EGR valve. When the coolant temps warm up, this valve closes and vaccume/boost reaches the EGR valve, thereby allowing it to open.

You may just want to add a EGR blockoff plate if this is not connected anymore as your EGR may be leaking.

Also the coolant temp sensor on the housing is used by the ECU to determine fuel/timing. If below a certain temp (or not connected at all), you will run hog rich and have crappy timing (ECU's safe mode). I had a situation where my Thermostat failed open so my car never reached operating temp and had the same problem

 

[DSM90AWD]

#1 is the 2 bent prongs that I have a female connector on. They should be like this l l but they are bent like a V.

#2 Is the thing with the vacuum lines?

#3 Is the 1 horizontal male and 1 vertical male, T, with a rubber fitting that goes over it.

#1 Is the Temp sensor for the ECU, this has to be working and hooked up or your engine will run like poopy

#2 As I said above is the Thermovalve for the EGR

#3 Is the A/C fan temp sensor which makes both fans come on high when the engine is running at operating temp and the A/C is on.

BTW, that is a 1990 housing, got one of them myself

 

[blackGSX2g]

That's the EGR's Thermo-valve. One nipple connects to one of the TB ports that leads to the back of the throttle plate, the other to a port at the front of the throttle plate. Both connect to the EGR valve. When cold the thermo-valve is open so no vacume reaches the EGR valve. When the coolant temps warm up, this valve closes and vaccume/boost reaches the EGR valve, thereby allowing it to open.

You may just want to add a EGR blockoff plate if this is not connected anymore as your EGR may be leaking.

Yea, what John is talking about looks like this:

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Easily eliminated and should get rid of a source of problems.

 

[Spoolin98]

Ok well first off, when the motor was out I did put a EGR block off plate in. So if this is a 1990 housing, why does it not look anything like FemmeDSM's housing on page 1 of this thread? Is the 90 housing better for some reason? The car does not have A/C, so I guess #3 doesn't matter.
DSM90AWD, which sensor controls the temp gauge in the cluster? 1, 2, or 3?
Are all my sensors in the correct spots? Damien thinks they are in the wrong spots.
How do I go about eliminating the thermovalve?
I believe the Temp sensor for the ECU, #1 on my diagram, is from a 2g housing. The guy at autozone showed me both the 1g and 2g temp sensors. The 1g was a single male connector, which a female connector goes over. I have the female connector, but not the male. Instead I have a 2 male prongs, which was exactly like a 2g temp sensor. The prongs are bent together to fit a female connector over them.
Sorry if that was confusing.

 

[Spoolin98]

That's the EGR's Thermo-valve. One nipple connects to one of the TB ports that leads to the back of the throttle plate, the other to a port at the front of the throttle plate. Both connect to the EGR valve. When cold the thermo-valve is open so no vacume reaches the EGR valve. When the coolant temps warm up, this valve closes and vaccume/boost reaches the EGR valve, thereby allowing it to open.

You may just want to add a EGR blockoff plate if this is not connected anymore as your EGR may be leaking.

Also the coolant temp sensor on the housing is used by the ECU to determine fuel/timing. If below a certain temp (or not connected at all), you will run hog rich and have crappy timing (ECU's safe mode). I had a situation where my Thermostat failed open so my car never reached operating temp and had the same problem

If what is not connected anymore?

 

[blackGSX2g]

If what is not connected anymore?

He meant you should install an EGR block-off if those vaccum lines are no longer connected. Since you already have the block-off installed, those lines no longer matter.

Are all my sensors in the correct spots? Damien thinks they are in the wrong spots.

The sensors themselves can be placed anywhere inside the thermostat housing, as coolant flows over all of them and they are plugged into the vehicle wiring harness.

I'd post pics of how mine looks, but they look the same as what FemmeDSM posted.

The exposed plug that you pointed to just has the plastic shroud missing from it. Otherwise it looks like the correct sensor.

 

[Spoolin98]

He meant you should install an EGR block-off if those vaccum lines are no longer connected. Since you already have the block-off installed, those lines no longer matter.



The sensors themselves can be placed anywhere inside the thermostat housing, as coolant flows over all of them and they are plugged into the vehicle wiring harness.

I'd post pics of how mine looks, but they look the same as what FemmeDSM posted.

The exposed plug that you pointed to just has the plastic shroud missing from it. Otherwise it looks like the correct sensor.

From post #38, Which exposed plug are you referring to? If #1 is what your talking about, that is the one I spoke to the guy at autozone about, the new sensors do not have a plastic shrouding, and if they did I would not be able to get the female connector on.

 

[femmeDSM]

I believe the Temp sensor for the ECU, #1 on my diagram, is from a 2g housing. The guy at autozone showed me both the 1g and 2g temp sensors. The 1g was a single male connector, which a female connector goes over. I have the female connector, but not the male. .

The guy at Autozone just got it backwards, I believe. The ECT on a 1g is the two prong male connector, and on a 2g it's a single prong. You have the correct ECT for a 1g.

Most cars will technically start and run with the ECT not hooked up, they will just throw a code and the car will run like poop (as DSM90AWD aptly noted, ). I have heard of several cases where the car would not start at all with the ECT unplugged or faulty (just cranks and cranks, especially on a cold startup). However, my car was not one of them....When my ECT went bad, it just threw the code and tried to die at idle...

What BlackGSX2g said makes sense....I hadn't thought of it that way. Where the sensors are located on the thermo housing should not technically make a difference, since they all just read the temperature of the coolant flowing through the system.

 

[Spoolin98]

This is the sensor that Autozone told me belongs in the #1 spot(post 38). The same thing you linked me to.
Which is one single male connector. I even checked the screen myself, It was the right sensor for a 1g, but their computers aren't always correct.

Gauge Sending Unit: (Post 17)
http://www.diamondstarmotorsport.com...uge-sensor.jpg

 

[femmeDSM]

which sensor controls the temp gauge in the cluster? 1, 2, or 3?

By default, I would say #2 here, as the gauge sending unit is the smallest of the three, and (in mine at least) is the only sensor with a single prong male connector.