jtinreno

I've got a 95 4runner with about 126k on it and suddenly today the oil pressure gauge started reading high (almost pegged). Then I noticed the fuel gauge doing the same thing. Battery voltage and temp gauges seem to be OK and truck runs fine.

Since both gauges are screwing up I don't think its the sending units.

Is there a voltage regulator for the gauges some place. I measured the battery voltage and it was Ok at 13.5 with engine running. Any ideas? Thanks...

Brian R.

Welcome to the AF!

The only thing that comes to mind is have your alternator/voltage regulator tested. 13.5 V is at the very bottom end of voltages for alternator output. Test the voltage from the alternator hot lead to the chassis. Test it under load also. Many times when more than one of the instruments are acting screwy, it's the alternator.

Check the manual that is stickyed at the top of this forum.

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jtinreno

Thanks Brian, I'll let you guys know what I find.

fourwd1

Fuel gauge reading high is common in Toyotas after a few years.

Oil pressure being inaccurate is also not surprising.

Sending units for both go bad.

But definitely do some troubleshooting to make sure there is no real problem.

__________________
- - as seen in FOUR WHEELER magazine July 06 and OFF-ROAD magazine Feb 07 - -

84 4Runner - ARBed 5.29s F&R, 4.7 & 2.28 t-cases, Chevys, AP x-over, BudBuilt x-member, 2" drv trn lift, 36" TSLs, 30 spline Longs

80 something p/u - Buick 231 V6/TH-350 trans, Holley 4 bbl, Weiand intake, dual batts, dual tanks ...

89 4Runner - stock

jtinreno

Well, the alternator checks out Ok. I kind of figured as much, the way my life usually goes that would have been way too easy!

Before I tear the dash apart I think I'll test both sending units. Does anybody have the electrical specs for the oil sending unit? I hate to spend $50 bucks on a complete wiring diagram (ebay) just for this. Thanks in advance.

Brian R.

Might be cheaper/easier just to replace the sending unit. If replacing one of the sending units doesn't solve the problem for the corresponding gauge, it's time for rethinking. I would vote for replacing the oil sending unit first.

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fourwd1

Procedure for checking sending unit is in FSM, oil sender probably is too.
Check the FSM sticky at the top of the main page.

__________________
- - as seen in FOUR WHEELER magazine July 06 and OFF-ROAD magazine Feb 07 - -

84 4Runner - ARBed 5.29s F&R, 4.7 & 2.28 t-cases, Chevys, AP x-over, BudBuilt x-member, 2" drv trn lift, 36" TSLs, 30 spline Longs

80 something p/u - Buick 231 V6/TH-350 trans, Holley 4 bbl, Weiand intake, dual batts, dual tanks ...

89 4Runner - stock