Got her home - now working through issues and need some help!

[Kidasters]

Well - I have her at home. For a refresher - she is a 1984 3.2 Targa. Now - working through issues.

First - oil pressure gauge is always reading 5. Pegs out at 5 when you turn power on, before you even start the car. I figure that this is a non-grounded circuit, so is my sender shot? Checked the back of the gauge - and it seems fine. Any way to check the sender before I pull it?

Second - While messing with that - I tried to start her back up. Crank-crank-crank, but no fire. Seems like it wants to fire, but nothing. Lots of smoke and fuel smell in my garage. Any thoughts? Car supposedly hadn't run in 2 years. Started fine this morning, and I drove a few places before getting home. Put a tank of fresh gas in it and some seafoam before the long drive (about 20 - 30 miles). I thought it might be a plugged fuel filter - which leads to ...

Third - the fuel filter doesn't want to leave the car. I've gotten the upper fitting loose, but the lower one doesn't want to go. I think if I can get in there with some flare nut wrenches (17 mm and 19 mm) and get some leverage, I can get it loose. Any other thoughts?

Fourth - what is this set of electrical plugs behind the blower? The top one is broken. What do they do, and how do I fix?



Finally - this is the plastic pipe on the blower. I see a hole. Should there be a plug there? Hole is in the middle of the pic.



Hope to get these sorted soon, and just enjoy the ride.

Thanks,

Ken

[steely]

Ken,

The broken wire could be the Cylinder Head temp line.
The other 2 are the speed and rev sensor lines from the sensors on the flywheel/
Open either of these 2 up, and the car won't start.
Not sure if you can run w/o the CHT either - when did it break?
from this aspect, the sensor lines are on the right, the lines on the left go to the DME.
As for a fix, I can't see what is broken - do you still have the connectors?
Maybe it is mated and just not in the bracket? (sorry)

The hole in the tube accommodates a plastic cable holder - the cable is from the throttle to the cruise control.
You can live with this hole - the fan pushes air thru the exchanger for the cabin heat.

you're on the right track with t he fuel filter, but I can't answer the sending unit question.

[Kidasters]

Thanks Dan.

I don't know when the wire broke. Just found it today. The end that was in the small bracket was very brittle. Could have broke while I was working on the fuel filter today. Not sure. It is all mangled, I can tell you that.

I'll search the site for the cylinder head temp sensor.

Thanks,

Ken

[Kidasters]

I think you are right - I think it is the cylinder head temperature sensor.

How hard is this to replace with the engine in the car? I can see it on a parts diagram, and I know it's on the # 3 cylinder. Anyone ever do that?

Thanks,

Ken

PS - I'm still betting that the pressure sending unit is kaput...

[James Brown]

You have to use a flare wrench on those fittings. If the filter has not been changed in a few years, then there real tight.
The oil pressure problem is most likely a faulty ground or corrosion in the sending wire. there real sensitive to both things.

[steely]

Ken,

The CHT can be replaced in with the engine it, but it is a bugger. I think you either have to buy or fab (heat and bend) a wrench or slotted socket/ Some yoga and contortion is req'd - although I have no first hand experience. You are correct, a search (CHT) will help you better than I can. Removal of LR wheel may be in order to aid you. I have done the other 2 sensors successfully.

I saw you bought it recently and drove her, that why I asked out of curiosity.
I think you can buzz it out and if it reads ok (2K ohms I believe), you should be able to temporarily re-connect as a troubleshooting aide.

[Kidasters]

Thanks again guys.

I think I'm going to replace the CHT sensor. It's the "One plug" job, and it may have been kaput for years. Who knows? I found the great How To by Chuck Moreland as well as in the Tech Info page, so I think I can do it.

For the sending unit, I'm going to try one more thing. I'll bypass the entire line with an alligator clip on the sending unit, and one on the gauge. That should show me if it's the sending unit or not.

Thanks again!

Ken

[86 911 Targa]

Originally Posted by Kidasters

Well - I have her at home. For a refresher - she is a 1984 3.2 Targa. Now - working through issues.

First - oil pressure gauge is always reading 5. Pegs out at 5 when you turn power on, before you even start the car. I figure that this is a non-grounded circuit, so is my sender shot? Checked the back of the gauge - and it seems fine. Any way to check the sender before I pull it?

Second - While messing with that - I tried to start her back up. Crank-crank-crank, but no fire. Seems like it wants to fire, but nothing. Lots of smoke and fuel smell in my garage. Any thoughts? Car supposedly hadn't run in 2 years. Started fine this morning, and I drove a few places before getting home. Put a tank of fresh gas in it and some seafoam before the long drive (about 20 - 30 miles). I thought it might be a plugged fuel filter - which leads to ...

Third - the fuel filter doesn't want to leave the car. I've gotten the upper fitting loose, but the lower one doesn't want to go. I think if I can get in there with some flare nut wrenches (17 mm and 19 mm) and get some leverage, I can get it loose. Any other thoughts?

Fourth - what is this set of electrical plugs behind the blower? The top one is broken. What do they do, and how do I fix?



Finally - this is the plastic pipe on the blower. I see a hole. Should there be a plug there? Hole is in the middle of the pic.



Hope to get these sorted soon, and just enjoy the ride.

Thanks,

Ken

Ken,

Here is the CKT.



Using a multimeter, check for the 12V and ground at the gauge wiring.

I suspect that your sender or sender wire (Green/Red) is grounded.

Disconnect the wire at the gauge and the sender and see if it is grounded.

If not It's the sender.

Also, just put a piece of electrical tape on the heater duct hole.

And yes, the brown wir/white connector is your cylinder head temperature sensor wire.

Good luck,

Gerry

[rvctyjim]

For the head temp sensor I made a tool from a deepwell 14mm 6pointed socket.
I used a cut off wheel to slot it.

[Kidasters]

Using a multimeter, check for the 12V and ground at the gauge wiring.

I suspect that your sender or sender wire (Green/Red) is grounded.

Disconnect the wire at the gauge and the sender and see if it is grounded.

Gerry

Gerry -

Thanks for the info. Unfortunately, I'm a hack mechanic, and even worse at electrical troubleshooting. How to I check to see if the wire is grounded with a multimeter, with it disconnected from the gauge and the sender?

Thanks,

Ken

PS - Jim - I read your post a couple of days ago. Can't believe I'd already forgotten about the deepwell with the slot cut in it. I may have to make a similar tool!

Thanks,

KT

[86 911 Targa]

Originally Posted by Kidasters

Gerry -

Thanks for the info. Unfortunately, I'm a hack mechanic, and even worse at electrical troubleshooting. How to I check to see if the wire is grounded with a multimeter, with it disconnected from the gauge and the sender?

Thanks,

Ken

PS - Jim - I read your post a couple of days ago. Can't believe I'd already forgotten about the deepwell with the slot cut in it. I may have to make a similar tool!

Thanks,

KT

Ken,

Disconnect both ends of the Green/Red wire from the Gauge and the sender.

Select the Ohm scale on your meter.

Place one of the probes to ground.

Place the other probe on the Green/red wire.

You should read an open circuit.

If you do, the sender is defective.

If you read a short, the Green/Red wire is shorted to ground.

You may pm me.

Good luck,

Gerry

[myamoto1]

Easiest way to determine if your oil pressure sender is caput or it's the wire is to pull the wire off of the sender and ground it to the case. That should make your press sender drop to zero. If it doesn't, it's your wire (and still possibly the sender). Do a search under my name and you'll find a little write up on the test and R&R I did for mine.

[stlrj]

Originally Posted by Kidasters

Second - While messing with that - I tried to start her back up. Crank-crank-crank, but no fire. Seems like it wants to fire, but nothing. Lots of smoke and fuel smell in my garage. Any thoughts?

Sounds like it's flooded. Initiate "clear flood mode" by flooring the gas pedal while cranking and that should get it to fire up.



Cheers,

Joe

[Kidasters]

OK - did some stuff. Plugged the little prong on the remains of the CHT sensor into the plug and the car started! Yay!

So - we know that has to be fixed.

Checked the resistance of the line with the gauge and the sender unhooked. Open circuit. Checked it with the gauge hooked up - open circuit. Grounded the wire to the case with the car on, gauge still reads 5.

With the car running, and the sending unit going through the multi-meter grounded to the case, I'm reading about 230 some ohms. Looks like the sending unit is fine.

Any tips on re-wiring the unit?

Thanks,

Ken

[86 911 Targa]

Originally Posted by Kidasters

OK - did some stuff. Plugged the little prong on the remains of the CHT sensor into the plug and the car started! Yay!

So - we know that has to be fixed.

Checked the resistance of the line with the gauge and the sender unhooked. Open circuit. Checked it with the gauge hooked up - open circuit. Grounded the wire to the case with the car on, gauge still reads 5.

With the car running, and the sending unit going through the multi-meter grounded to the case, I'm reading about 230 some ohms. Looks like the sending unit is fine.

Any tips on re-wiring the unit?

Thanks,

Ken

Ken,

It would appear that your line from the sending unit to the gauge is grounded.

Remove the wire at both ends, put one side of the meter to ground, and the other side on the green/red wire.

You should read an open circuit.

If you read an open ckt, and you have verified that the sender is working, check the connections at the gauge as per the ckt I sent you.

[rvctyjim]

You should test ohms from the big connector Disconnected (in the engine fuse box) to the sending unit connected and see if you get a ohms reading from there.

#4 green/red wire is what you are looking for

If you do not see any ohms :You have wire/connection problem from the big connector to the sender(broken wire,connector not contacting sender good enough)

If you do see ohms at big connector(disconnected):you have a pin-fit problem at the big connector(the connecton between the two halvs of the big connector in fuse box) or problem is inbetween wiring harness side connector and gauge.

To Check for pin-fit problem at big connector.backprobe Ohms check both sides of big connector.

[86 911 Targa]

As per our telecon, there are only two option that come to mind:

1. The gauge wiring is transposed (Red/Black-Green White).

Or:

2. The gauge movement is defective.

Gerry