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Sensor under plenum??

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Old Nov 10, 2016 | 12:29 PM
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Default Sensor under plenum??

I am replacing the injectors on my 1990 coupe after a hydrolock issue steming from either a stuck injector or bad FPR. I am replacing all injectors and putting in a new diaphragm for the FPR.

I have the plenum off and see that there is a sensor screwed directly into it underneath. It had some oil on it. What is that sensor for and should I replace it now that the plenum is already off?

Thanks
Wade
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Old Nov 10, 2016 | 01:13 PM
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If brass & a screw in its the Intake air temp sender. Some like to relocate it in front of the throttle body. If interested in that mod the search feature here will help.
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Old Nov 10, 2016 | 02:15 PM
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Originally Posted by clovergamecock
I am replacing the injectors on my 1990 coupe after a hydrolock issue steming from either a stuck injector or bad FPR. I am replacing all injectors and putting in a new diaphragm for the FPR.

I have the plenum off and see that there is a sensor screwed directly into it underneath. It had some oil on it. What is that sensor for and should I replace it now that the plenum is already off?

Thanks
Wade
you said .......... "or BAD FPR" - has it been proven too be BAD or you're just going from what you told could be? Until proven faulty I don't believe that is an FPR that just demands a "change for the HE!! of it.
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Old Nov 10, 2016 | 03:16 PM
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Originally Posted by WVZR-1
you said .......... "or BAD FPR" - has it been proven too be BAD or you're just going from what you told could be? Until proven faulty I don't believe that is an FPR that just demands a "change for the HE!! of it.
The issue is with a stuck injector but since the plenum is off and the FPR is 26 years old it is worth the $50 to go ahead and replace the diaphragm.
If the other one is still good then I will throw it in a drawer incase of emergency.

W
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Old Nov 10, 2016 | 03:31 PM
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Originally Posted by clovergamecock
The issue is with a stuck injector but since the plenum is off and the FPR is 26 years old it is worth the $50 to go ahead and replace the diaphragm.
If the other one is still good then I will throw it in a drawer incase of emergency.

W
and change the oil do not want a grenade.
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Old Nov 11, 2016 | 12:09 AM
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Originally Posted by clovergamecock
The issue is with a stuck injector but since the plenum is off and the FPR is 26 years old it is worth the $50 to go ahead and replace the diaphragm.
If the other one is still good then I will throw it in a drawer incase of emergency.

W
If you are there already, I would.
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Old Nov 11, 2016 | 07:43 AM
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I have the rail off, new injectors in and FOR diaphragm replaced. Looks like 2 injectors were changed. Those are missing the lower clip. One is missing upper and lower. Where can I get these
Can the injectors be installed without them since the rail zits on top?

Getting oil this morning and looks like valve cover gaskets. 1 has a bad leak. Felpro rubber?

Last, is it possible that the oil pan was filled with so much gas that it either started coming out of the dip stick tube to block or blew a front rear seal.? Bottom of motor is covered and dropping a bunch on the floor especially when I jacked up driver side up. This is completely new.

W
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Old Nov 11, 2016 | 07:52 AM
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Originally Posted by clovergamecock
I have the rail off, new injectors in and FOR diaphragm replaced. Looks like 2 injectors were changed. Those are missing the lower clip. One is missing upper and lower. Where can I get these
Can the injectors be installed without them since the rail zits on top?

Getting oil this morning and looks like valve cover gaskets. 1 has a bad leak. Felpro rubber?

Last, is it possible that the oil pan was filled with so much gas that it either started coming out of the dip stick tube to block or blew a front rear seal.? Bottom of motor is covered and dropping a bunch on the floor especially when I jacked up driver side up. This is completely new.

W
If they cannot, mine should be leaking so I guess they can. If you are in doubt, give Megan a call at FIC.

L98 never did have a history of dryness. I watched my tech seal it when I had arm surgery. Did EXACTLY the same thing both times and 3rd time was the charm.

Anything is possible but lets start with cleaning the motor up after you seal the VC and see where it leaks from with dye.
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Old Nov 11, 2016 | 12:35 PM
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HOLY CRAP!!!! Just drained the oil, came out thin with a strong smell of gas. It filled up an entire drain pan and a 1/4 of another!.
Filter is off I am leaving it off and the drain plug out while I am more putting everything back togather. As slow as I am it will probably be 24 hours.

The motor is soaking in engine degreaser now.

Last edited by ImBatman; Nov 11, 2016 at 12:37 PM. Reason: Wrong words
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Old Nov 11, 2016 | 01:21 PM
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Per Jon at FIC it is ok to leave the clips off. During assembly the fuel rail and injectors rode on an overhead line. The clips kept the injectors from falling out during their ride. The clips that hold the harness to the injectors should remain in place though.
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Old Nov 11, 2016 | 01:34 PM
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Originally Posted by clovergamecock
HOLY CRAP!!!! Just drained the oil, came out thin with a strong smell of gas. It filled up an entire drain pan and a 1/4 of another!.
Filter is off I am leaving it off and the drain plug out while I am more putting everything back togather. As slow as I am it will probably be 24 hours.

The motor is soaking in engine degreaser now.
I'd probably run some cheap oil and filter in it for a bit then drain and replace with better oil and filter.
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Old Nov 11, 2016 | 05:03 PM
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Originally Posted by aklim
I'd probably run some cheap oil and filter in it for a bit then drain and replace with better oil and filter.
Thanks! I have all of the harness click so I'm good


Originally Posted by corvetteronw
Per Jon at FIC it is ok to leave the clips off. During assembly the fuel rail and injectors rode on an overhead line. The clips kept the injectors from falling out during their ride. The clips that hold the harness to the injectors should remain in place though.
Yep QUAKER STATE 5-30 and accessories filter. Less than 20 bucks.

I am still speechless about the amount of fuel in the pan. It was essentially filled to the top. No wonder there is oil all under the car. It looks like it was coming out of the dip stick.

SCARY!!!!!!!

Wade
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