Oil pressure sender

[Paubrannan]

I've just changed the oil in our new (to us) 78 FJ40. Changed the filter as well and now the pressure gauge is reading nothing (way below the L so you ant as the arm). Engine sounds fine, looks like fresh oil in the top. The old oil was very black, is it possible something in the sensor got blocked? Many thanks.

 

[65swb45]

You bumped the wire on the sender when you changed the filter. Wiggle it.

 

[Paubrannan]

Or could it be something to do with the filter? I replaced the old wiz 51515 with a K&N HP 3001. Thanks

 

[Paubrannan]

You bumped the wire on the sender when you changed the filter. Wiggle it.

Thanks. I thought that. I've taken it off cleaned the connector and put it back on with no joy.

 

[Strait Cruisin]

Try taking the wire off the sensor and then ground it while observing the gauge. It should do a full scale deflection.

If the gauge does that, its the sensor. Is there oil leaking around the seams of the sensor?

 

[Paubrannan]

Thanks. It works when grounded. I'm now thinking the old connection may have been grounding all the time and hence the almost all the way to high reading. I'll replace the sensor and see how we do.

 

[bj40green]

Thanks. It works when grounded. I'm now thinking the old connection may have been grounding all the time and hence the almost all the way to high reading. I'll replace the sensor and see how we do.

TIP: Buy OEM from the dealer.

 

[emac]

Good tip on buying oem. I had two aftermarkets go bad. I would try removing the old sensor spray it out with brake cleaner and try it again. it may just be gunked up. It helped revive mine.

There is athread about taking them apart and cleaning/adjusting them. That may seem silly, until you see the cost of OEM.

 

[brian]

oem is available for around 70 bucks

 

[Michael Hanson]

Hi, Just bought one for 60. Mike

 

[Paubrannan]

So.....I bought an OEM unit, installed it. No pressure registers on gauge. Put new connector on the wire, did the earth test and the gauge goes to high pressure. Any ideas? It can't be the change of oil filter can it?

 

[bj40green]

Check if oil comes out when you remove the sender and crank the engine.

Rudi

 

[Paubrannan]

Check if oil comes out when you remove the sender and crank the engine.

Rudi

There was no oil on the old one I removed. I'll try that. Garage floor needs to be cleaned anyway! Thanks very much

 

[Strait Cruisin]

So.....I bought an OEM unit, installed it. No pressure registers on gauge. Put new connector on the wire, did the earth test and the gauge goes to high pressure. Any ideas? It can't be the change of oil filter can it?

Verify the engine to body is grounded and there is no resistance between body-frame-engine. When performing the grounding test, did you ground against the motor or body? Other than than, open a vein and see what comes out.

 

[bj40green]

Verify the engine to body is grounded and there is no resistance between body-frame-engine. When performing the grounding test, did you ground against the motor or body? Other than than, open a vein and see what comes out.

If it's a ground problem the temp circuit will have the same problem.

Rudi

 

[Paubrannan]

Arrrrrrgggggggghhhhhhh......ok, from the top:

1. Bought car, oil pressure high
2. Changed oil and filter, engine sounds fine, gauge not working
3. Earth wire from gauge, works.
4. bought new sender re did the connection guage still doesn't register anything, still works if earthed.
5. Took sender off. Started engine, spent 30 mins cleaning the floor, plenty of oil coming through.

I have now surpassed the level of my own competence.

I don't think the wire was badly connected and earthed before I changed the oil. Don't know when the oils was last changed and the old oil was fairly black.

Could it be the gauge itself even although it registers when earthed?
Is it possible to have enough oil in the engine but the pressure too low to register anything on the gauge?

Any help much appreciated, I really want to try and do this myself and not give in and take it to the local mechanic.

Thanks

 

[brian]

Replace the sender with a 0-100psi or so gauge... right in the block were the sender should be.
Fire the ol girl up and see what you have....its going to have pressure. I'm positive you have an electrical gremlins not a mechanical issue.

 

[4Cruisers]

Replace the sender with a 0-100psi or so gauge... right in the block were the sender should be.

An aftermarket sender will more than likely have 1/8-27 NPT threads, but it will work OK temporarily with the BSPT threads in the block. If you go that route and make it permanent adapters between the two threads can be found on eBay or Amazon.

 

[bj40green]

1. Did you buy the original Sender from the Toyota dealer # 83520-55011 ?

or #83520-35020 Is the same but with a ground terminal

2. I hope you didn't use teflon tape or any other (insulation) stuff because the sender has to make ground contact to the engine.

Rudi

 

[kurtnkegger]

Could it be the K&N filter bypasses enough that the oil pressure reads low?