I have a 1998 Chevrolet C 1500 5.7 Vin R. Oil Pressure low after changing oil. Is the Sending Unit bad?

Question

Wojo1973

I have a 1998 Chevrolet C 1500 5.7 Vin R. Oil Pressure low after changing oil. Is the Sending Unit bad?

I changed the oil and filter 300 Miles ago. After the oil change the gauge read in the upper half when starting.Now the oil pressure gauge reads lower 1/2 and drops after engine warms up and sometime near zero. Oil level still full on dipstick. Engine sounds normal; no lifter noise like. Thought maybe the oil filter bypass might be the problem but oil pressure still low after installing another AC PF1218. Leaning toward Oil Sending unit malfunction. Viewed several videos on Youtube but none specific to my 1998 C1500 5.7 Liter (VIN R Vortec).Need to locate the sending unit and guidance to troubleshoot and replace the part if bad. Assistance Appreciated.

Status: Open Sep 15, 2022 - 07:21 AM

Chevrolet

Comments (0) | New Comment

Do you have the same question? Follow this Question

Answer this question Report it

5answers

Voted Best Answer

dexterjosephmundodiaz

Sep 15, 2022 - 02:28 PM

1998 chevy c1500 8 cyl 4.7 , OE number 93427692 LT1/LT4 High-Pressure Oil Pump - What's the current mileage and , when is the last time the vehicle had a timing chain maintenance replacement . Depending on the current mileage I will recommend an engine cylinder pressure test First .

3

0

Report it

Comments (1) | New Comment

Answers

loopictam

Oct 02, 2022 - 11:55 AM

If the engine has high miles on it, bearing clearances are getting larger and will result in lower oil pressure. Try using a heavier weight oil or try a can of STP additive and see if the pressure comes up with thicker oil. Try that first just to see before spending money on the sending unit.

3

0

Report it

Comments (2) | New Comment

Mitch_CarParts.com

Oct 07, 2022 - 11:17 AM

Hello!

Oil pressure sender failures are fairly common, and unfortunately it's fairly difficult to diagnose. I use an adapter to connect an analogue gauge to make sure that the oil pressure is actually OK before replacing the sender. If the oil pressure is actually low, then I would consider pulling the oil pan to check the condition of the oil pump and crankshaft bearings.

Mitchell D
ASE Master Automobile Technician
Certifications: ASE-Certified Master Automobile Technician, SFI-Certified Safety Inspector
>>> Right Parts, Right Now at CarParts.com

1

0

Report it

Comments (1) | New Comment

Yeakeyboy70

Aug 17, 2023 - 08:35 PM

Yes it could very well be bad. I would recommend changing the oil send sending unit and that will probably be the end of the problem.

1

0

Report it

Comments (1) | New Comment

Jay_CarParts.com

Aug 23, 2023 - 11:53 AM

Hi there,

If there is sudden drop in oil pressure after you happen to do an oil change. It could possibly point to a faulty oil pressure sending unit/gauge. The oil pressure gauge is a device that keeps track of the oil pressure in the engine. Insufficient pressure will slow engine oil flow, leading to engine issues like overheating and premature wear. Click this link for more info from one of our CarParts Blog resource. This other CarParts Blog link is related and may be helpful as well. I hope this helps!

0

Report it

Comments (0) | New Comment

Answer this question

Share Your Own Experience & Expertise

We look to ensure that every question is answered by the best people with relevant expertise and experience, the best answers include multiple perspectives. Do you have relevant expertise or experience to contribute your answer to any of these commonly asked questions?

Thank You for the response: I ultimately located the oil sending Unit on the rear of the engine near the distributor, a circuit diagram, and testing procedure with multimeter. Upon removing the connector from the unit I found oil inside the sender so I purchased a new sending unit. Replacing it restored the Low oil pressure. Because this switch also controls fuel pump engagement the engine started quicker.
Thanks for the suggestion!

Mitchell D
ASE Master Automobile Technician
Certifications: ASE-Certified Master Automobile Technician, SFI-Certified Safety Inspector
>>> Right Parts, Right Now at CarParts.com
Thank You for the response: I ultimately located the oil sending Unit on the rear of the engine near the distributor, a circuit diagram, and testing procedure with multimeter. Upon removing the connector from the unit I found oil inside the sender so I purchased a new sending unit. Replacing it restored the Low oil pressure. Because this switch also controls fuel pump engagement the engine started quicker.

I have a 1998 Chevrolet C 1500 5.7 Vin R. Oil Pressure low after changing oil. Is the Sending Unit bad?

5answers

Voted Best Answer

Answers

Share Your Own Experience & Expertise

Related Content

Browse by Part (optional)

Browse by Topic

Shopping Hubs

NEW PERKS ARE AN EMAIL AWAY!