What are these 3 items ?

[R_W_B]

(1988 Chevy C1500, 350ci, 5.7L, TBI)
Can you guys tell me what these 3 items are and do ?

1. The first (left) one is some kind of senser on the driver side just behind number 1 cylinder, in between the 2 spark plugs.
2. The second (middle) one is located at rear of engine just behind intake manifold (manifold removed).
3. The last (right) one is right above the oil filter. It is connected in the block at the top of the oil filter.

I "think" #3 is the oil pressure sending unit. I have no idea what the other two are.

 

[fun4me]

The first one is the temp sender for the temp gauge, the second one is a low oil pressure switch for the fuel pump, & the third one is the oil pressure sender for the oil pressure gauge.

 

[DRAGGIN95]

The first one is the temp sender for the temp gauge, the second one is a low oil pressure switch for the fuel pump, & the third one is the oil pressure sender for the oil pressure gauge.

Winner, winner, chicken dinner!

 

[R_W_B]

The first one is the temp sender for the temp gauge, the second one is a low oil pressure switch for the fuel pump, & the third one is the oil pressure sender for the oil pressure gauge.

Ah ok so there are 2 oil pressure senders, and one is dedicated for the fuel pump only. Now on the one between the plugs, I'm kinda confused again since I though this one on the intake manifold next to the thermostat housing, was the temp sender ?

 

[DRAGGIN95]

The coolant sender on the intake is the one for the ECM only.

 

[DRAGGIN95]

Also 88+89 truck's used 2 oil pressure senders, 1 for the oil pressure gauge and 1 like mentioned above for the dummy light, I have modified a couple pre 90 model's to use the 1990+ sender which combines the 2 in to 1 unit, it requires the 90+ sender and wiring pigtail.

 

[R_W_B]

Also 88+89 truck's used 2 oil pressure senders, 1 for the oil pressure gauge and 1 like mentioned above for the dummy light, I have modified a couple pre 90 model's to use the 1990+ sender which combines the 2 in to 1 unit, it requires the 90+ sender and wiring pigtail.

Thanks for the excellent data. BTW this site does not notify my email of replies. I have double checked my profiles settings for correct email address and notification status to "instant email" but I have never gotten one email notice from this forum. Does anybody else have this problem ?

 

[454SSguy]

It will only email you if you are subscribed threads. You can change what "subscribes" you to a thread to posting and it will email you then.

 

[DRAGGIN95]

It will only email you if you are subscribed threads. You can change what "subscribes" you to a thread to posting and it will email you then.

It's time for you to have some REP.

 

[///RAGMC]

Also 88+89 truck's used 2 oil pressure senders, 1 for the oil pressure gauge and 1 like mentioned above for the dummy light, I have modified a couple pre 90 model's to use the 1990+ sender which combines the 2 in to 1 unit, it requires the 90+ sender and wiring pigtail.

My truck only has the 1 sensor I bought it that way